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Middle paleogene palynology of Colombia, South America

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Title:
Middle paleogene palynology of Colombia, South America biostratigraphic, sequence stratigraphic, and diversity implications
Creator:
Jaramillo, Carlos A., 1969-
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Language:
English
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x, 417 leaves : ill. ; 29 cm.

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Subjects / Keywords:
Coastal plains ( jstor )
First appearance datums ( jstor )
Palynofacies ( jstor )
Palynomorphs ( jstor )
Pollen ( jstor )
Sediments ( jstor )
Species ( jstor )
Stratigraphy ( jstor )
Taxa ( jstor )
Trucks ( jstor )
Dissertations, Academic -- Geology -- UF ( lcsh )
Geology thesis, Ph.D ( lcsh )
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bibliography ( marcgt )
non-fiction ( marcgt )

Notes

Thesis:
Thesis (Ph.D.)--University of Florida, 1999.
Bibliography:
Includes bibliographical references (leaves 397-416).
General Note:
Typescript.
General Note:
Vita.
Statement of Responsibility:
by Carlos A. Jaramillo.

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University of Florida
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Copyright [name of dissertation author]. Permission granted to the University of Florida to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
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030475331 ( ALEPH )
43164569 ( OCLC )

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MIDDLE PALEOGENE PALYNOLOGY OF COLOMBIA, SOUTH AMERICA: BIOSTRATIGRAPHIC, SEQUENCE STRATIGRAPHIC, AND DIVERSITY IMPLICATIONS












By



CARLOS A. JARAMILLO


A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY

UNIVERSITY OF FLORIDA


1999














ACKNOWLEDGMENTS


First and foremost, I wish to thank my advisor, Dr. David L. Dilcher. His advice, encouragement, constructive criticism, and help were instrumental in the success of this project. I would like to thank the members of my committee Drs. David Hodell, Douglas Jones, Walter Judd, Steven Manchester, and Neil Opdyke for their continuous support. I am grateful to German Bayona for his assistance during the field season. Thanks go to Drs. Fernando Etayo and Tomis Villamil for encouraging me to pursue a Ph.D. I would like to thank Dr. David Jarzen, and Ricardo Holdo for discussion about palynological and statistical matters. The Corporaci6n Geol6gica Ares provided valuable logistic support.

This study was funded by the National Science Foundation, Colciencias, the Fundaci6n para la Promoci6n de la Investigaci6n y la Tecnologfa Banco de la Repdblica, the Geological Society of America, the American Association of Petroleum Geologists, the American Association of Stratigraphic Palynologists, the University of Florida's College of Liberal Arts and Sciences, the Department of Geology, and the Florida Museum of Natural History.

My gratitude goes to Rodolfo Dino from Petrobras, Henry Hooghiemstra from the University of Amsterdam, Roel Verreussel from the University of Utrecht, and Estela de DiGiacomo from Pedevesa, for allowing me to visit their palynological collections. Graham Williams and Jonathan Bujak helped me with the dinocyst identifications. I am also grateful to all the people who helped me during my field season in the towns of Sabanalarga, Uribe-Uribe, and Cdcuta.

Special thanks go to my parents who have patiently supported me through the many years of my schooling, and to my wife, Maria Inds Barreto, who has kept me alive.


ii















TABLE OF CONTENTS
page


ACKNOWLEDGMENTS ...................................... 1

L IST O F T A B LE S................................................................................. v

LIST O F FIG U R E S ............................................................................... vi

A B ST R A C T ........................................................................................ ix

CHAPTERS

1 IN T R O D U C T IO N ............................................................................. 1

2 O B JE C T IV E S .................................................................................. 4

3 MATERIALS AND METHODS ............................................................ 5

4 REGIONAL GEOLOGICAL SETTING.................................................. 17

5 BIOSTRATIGRAPHY....................................................................... 20

Previous Studies............................................................................. 22
R e su lts .......................................................................................... 4 4
D iscussion .................................................................................. ... 79

6 SEQUENCE STRATIGRAPHY........................................................... 90

Palynofacies.................................................................................. . 9 1
Previous Studies .......................................................................... 9 1
R esults ................................................................................ . ... 9 2
D iscu ssion ............................................................................... 10 7
Paleoecology ................................................................................. 111
Previous Studies ........................................................................ 111
R esu lts ................................................................................... 1 12
D iscu ssion ............................................................................... 1 19
L itho lo gy ..................................................................................... 12 7
P revious S tudies ........................................................................ 127
R esu lts ................................................................................... 13 6
Sequence Stratigraphy Interpretation...................................................... 148
Previous Studies ........................................................................ 148
R e su lts ................................................................................... 15 7
D iscu ssion ............................................................................... 160


iii









7 D IV E R SIT Y ................................................................................. 176

Previous Studies............................................................................. 178
R esu lts ........................................................................................ 17 9
D iscussion .................................................................................... 189

8 CONCLUSIONS............................................................................ 200

APPENDICES

A TAXONOMIC DESCRIPTIONS ......................................................... 205

B LITHOLOGICAL DESCRIPTION OF THE PINALERITA SECTION............. 353

C LITHOLOGICAL DESCRIPTION OF THE REGADERA SECTION .............. 379

D LITHOLOGICAL DESCRIPTION OF THE URIBE SECTION ..................... 386

REFERENCES .................................................................................. 397

BIOGRAPHICAL SKETCH................................................................... 417


i v
















LIST OF TABLES


Table page


3-1. O rganic m atter classification ............................................................... 12

5-1. Pollen and spores named from the Paleogene of northern South America ........... 24

5-2. Botanical affinities for fossil sporomorphs from northern South America .......... 31

5-3. Palynomorph distribution in samples from the Pifialerita section.................... 56

5-4. Palynomorph distribution in samples from the Regadera section.................... 67

5-5. Palynomorph distribution in samples from the Uribe section........................ 70

5-6. First and last appearance datums and abundace peaks for 84 taxa used in
graphic correlation ...................................................................... 73

5-7. Fossil events used in the final Composite Section..................................... 76

5-8. Datums used for calibration of Composite Section.................................... 78

6-1. Palynodebris count data (in %) for the Pifialerita section..............................101

6-2. Palynodebris count data (in %) for the Regadera section..............................103

6-3. Palynodebris count data (in %) for the Uribe section ..................................105

6-4. Previous paleoecological interpretations for sporomorphs found in this study .....114 6-5. Abundance of selected taxa used in paleoecological analysis .........................116

7-1. Sporomorph species shared by Africa, Gulf Coast, and Caribbean/Central
America with Northern South America................................................191


v















LIST OF FIGURES


Figure page


3-1. Geologic map of Colombia showing the three sections studied........................ 6

4-1. Sedimentary tectono-stratigraphic provinces of Colombia.............................. 19

5-1. Range chart for Angiosperm fossil pollen in Northern South America............ 23

5-2. Ranges of foraminifera used to calibrate Germeraad palynological zonation... 36 5-3. Comparison of Germeraad, Regali and Muller zonations .............................. 42

5-4. First round of correlation. Pifialerita (Reference Section) versus Regadera..... 46 5-5. First round of correlation. Composite Section versus Tibui........................... 47

5-6. First round of correlation. Composite Section versus T4 and Uribe sections ... 48 5-7. Second round of correlation. Composite Section versus Regadera................ 49

5-8. Second round of correlation. Composite Section versus Tibui....................... 50

5-9. Second round of correlation. CS versus T4 and Uribe sections ...................... 51

5-10. Second round of correlation. Composite Section versus Pifialerita................ 52

5-11. Correlation for well TI, Regadera, and Tibui sections versus CS................... 53

5-12. Correlation for Uribe and Pifalerita sections versus Composite Section........ 54 5-13. Correlation for Rubio Road and Paz de Rio sections versus CS ..................... 55

5-14. Line of correlation for Imo section and Itori well versus CS ......................... 80

5-15. Line of correlation for Ovim and Benin section versus CS............................. 81

5-16. Summary of calibration datums for the Composite Section ............................ 82

5-17. Berggren et al. (1995) chronology of the late Paleocene-Eocene epochs........ 87

6-1. Palynofacies of Pifialerita section .................................................................... 94

6-2. Palynofacies of Regadera section ................................................................... 95


vi









6-3. Palynofacies of U ribe section .......................................................................... 96

6-4. Average linkage cluster analysis of palynofacies in the Pifialerita section ...... 97 6-5. Organic matter content of each of palynofacies group, Pifialerita section ........ 98 6-6. Cluster analysis of palynofacies in the Regadera and Uribe sections.............. 99

6-7. Content of palynofacies groups for Regadera and Uribe sections..................... 100

6-8. Non-metric multidimensional scaling analysis.................................................. 113

6-9. Paleoenvironmental interpretation of Pifialerita section.................................... 124

6-10. Paleoenvironmental interpretation of Regadera section .................................... 125

6-11. Paleoenvironmental interpretation of Uribe section .......................................... 126

6-12. Schematic representation of the major divisions of fluvial environment .......... 137

6-13. Schematic representation of the major divisions of delta environment............. 138

6-14. Schematic representation of the major divisions of estuary environment ......... 139

6-15. Sequence stratigraphic interpretation for Pifialerita section .............................. 140

6-16. Sequence stratigraphic interpretation for Regadera section.................... .......... 141

6-17. Sequence stratigrphic interpretation for Uribe section ...................................... 142

6-18. Cooper and Cazier sequence stratigraphic models ............................................ 150

6-19. Previous sequence stratigraphic models for Colombian Llanos foothills.......... 155

6-20. Relationship of lithospheric flexure to accomodation in foreland systems ....... 162 6-21. Sequence stratigraphy and subsidence profile across foreland basins............... 163

6-22. M iddle M agdalena B asin ................................................................................... 166

6-23. Sequence stratigraphy interpretation for the Llanos foothills, Colombia.......... 167

6-24. Simplified map of the Llanos foothills, Colombia............................................. 169

6-25. Schematic location of Pifialerita section in a incised-valley filling................... 171

6-26. Regional correlation of sections with palynological information...................... 173

6-27. Lithostratigraphy of sections with palynological information........................... 175

7-1. Diversity analyses. A. DCA B. -loge(Simpson index) .................................. 181

7-2. Rarefaction curves for Pifialerita sam ples.......................................................... 182


vii









7-3. Rarefaction curves for highstand systems tract samples from Pifialerita .......... 183

7-4. Rarefaction curves for transgressive systems tract samples from Pifialerita..... 184 7-5. Diversity analyses. A. Standing diversity. B. FAD and LAD rates................. 185

7-6. Diversity analyses excluding single-occurrence taxa ........................................ 187

7-7. Diversity analyses. A. FAD/LAD proportions. B. floras................................. 188

7-8. Paleogeographic map of the early middle Eocene............................................. 190


viii














Abstract of Dissertation Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy

MIDDLE PALEOGENE PALYNOLOGY OF COLOMBIA, SOUTH AMERICA: BIOSTRATIGRAPHIC, SEQUENCE STRATIGRAPHIC, AND DIVERSITY IMPLICATIONS

By

Carlos A. Jaramillo

August 1999


Chairman: David L. Dilcher
Major Department: Geology


The late Paleocene-early Eocene interval is characterized by a long period of global warming that culminated with the highest temperatures of the Tertiary. This time interval is associated with plant extinctions and a subsequent increase in plant diversity in mid and high latitudes. However, data from tropical regions remain largely unknown. This time interval is also of strategic interest in northern South America because most oil reservoirs occur in Paleogene strata where detailed chronostratigraphy is necessary to develop a clear understanding of stratigraphy and structural geology.

I analyzed the palynostratigraphy of three areas in the Colombian Eastern Andes (northern Middle Magdalena, Llanos Foothills, and southern Catatumbo) with the aim of achieving three major goals: a) to produce a time-framework using pollen, spores, and dinoflagellates; b) to develop a sequence stratigraphic interpretation for each section using palynofacies, paleoecology, and lithofacies; and c) to look for patterns of pollen and spores diversity through the late Paleocene-Eocene interval.

A biostratigraphic framework was built using graphic correlation. Dating sections indicate that there is not a significant time gap encompassing the early and middle Eocene in


ix









all of Colombia as previous authors had interpreted. Also, it is clear that formational boundaries of the Paleocene-Eocene formations do not correspond to epoch boundaries and cannot always be considered as chronostratigraphic surfaces. Sequence stratigraphic interpretations of each section indicate that it is not possible to establish a single sequence stratigraphic model for the three sections because they were in three different basins, isolated from each other, and with different subsidence histories, sediment sources, and stratal architecture. However, there are two events with regional significance: an earliest Eocene sequence boundary, and an early middle Eocene flooding surface.

The pollen/spores record indicates a relatively large extinction at the end of the

Paleocene and a subsequent increase in diversity during the early and early middle Eocene reaching levels higher that those of the late Paleocene. This extinction and subsequent increase in diversity may be correlated with the late Paleocene Thermal Maximum and Eocene Thermal Maximum, respectively. This demonstrates that variability in tropical climate may have played an important role in the development of plant diversity in the neotropics.


x















CHAPTER 1
INTRODUCTION



Colombian stratigraphy is mainly composed of Tertiary continental sedimentary

rocks. These strata are in structurally complex areas related to the Pliocene Andes uplift further complicating an adequate understanding of the Tertiary stratigraphy. For the last 60 years, intensive geological exploration of Colombian Tertiary rocks has been carried out. Most of this work has been related to oil exploration. Unfortunately, only a small fraction of this information has been published.

The Paleocene-Eocene history of northern South America has been the focus of many researchers since the 1950s (Van der Hammen, 1954; Gonzalez, 1967; Muller et al., 1987). Still, this time interval remains poorly known and more detailed geologic research is necessary. Important large-scale events developed during the Paleogene such as the Eocene Thermal Maximum (Miller et al., 1987), the Andes uplift process (EtayoSerna et al., 1983), and the initial closure of the Tethys. More information on those subjects from neotropical areas is necessary for an adequate understanding of them. The Paleogene history of northern South America is also important regionally because the most important hydrocarbon reservoirs in the region are located in Paleocene and Eocene continental rocks. These reservoirs are frequently located in zones with high structural complexity where an excellent biostratigraphic framework is crucial toward understanding the stratigraphy, defining oil-bearing structures, and planning new exploration targets.

Three subjects in need of more intensive research are evident in the geology of this area: lack of a high-resolution chronostratigraphic framework, lack of basin-focused sequence stratigraphic models, and the unknown effects of the Eocene Thermal


1







2


Maximum on tropical vegetation. These three problems could be addressed using fossil data coupled with stratigraphic analyses.

The most abundant fossils present in the Paleogene sediments of continental

Colombia are palynomorphs and particulate organic matter. The word "palynomorph" is used here to indicate pollen, spores, and dinoflagellates; "sporomorph" indicate pollen and spores, while "palynofacies" indicates the assemblage of particulate organic matter (Traverse, 1988). Relatively little published information exists on Colombian palynology; this may be due to the confidentiality of information used by various oil companies operating in the area. However, previous palynologic studies in the region (Gonzalez, 1967; Germeraad et al., 1968) reported highly diverse and abundant pollen/spores assemblages and showed that sporomorphs are the most reliable biostratigraphic and paleoecological tool in terrestrial Paleogene strata of Colombia.

One of the major problems in integrating geologic information produced in

neotropical areas, especially Colombia, with the rest of the world is the lack of a truly high resolution chronostratigraphic framework. For the last 30 years, a local system for placing events in a temporal order has been developed in the tropics. This system for the Paleocene-Eocene interval relies on pollen and spores because they are the most abundant fossils in continental deposits accumulated during this time. However, this system has a low resolution for the Paleocene-Eocene and it is poorly correlated with the international time scale. This time scale provides a single universal reference standard for dating rock strata or events in earth history with respect to the passage of geologic time (Berggren et al., 1995a). In other words, what tropical American geologists often call "late Paleocene", "early Eocene", etc., must be taken with caution, and be considered an informal name that does not bear exactly the same meaning as in the standard geologic time scale. A high resolution chronostratigraphic framework calibrated with the geologic time scale is urgently needed. Only then, can we truly start to use and integrate the geologic information produced in neotropics with the rest of the world.






3


An adequate understanding of the pollen and spores distributions as well as the facies control on their distributions require a stratigraphic understanding of the rocks containing them. Sequence stratigraphy has become the most reliable tool for studying strata in clastic sedimentary basins. Sequence stratigraphy is the study of genetically related facies within a framework of chronostratigraphically significant surfaces (Van Wagoner et al., 1990). This modem approach is widely used to study the hierarchical arrangement and spatial distribution of sedimentary deposits. Sequence stratigraphy was done using palynofacies, palynomorph paleoecology, and lithological analyses. The sequence stratigraphy analysis provided hypotheses for the general patterns of strata distribution and the geographical extent of transgressive and regressive episodes.

The effects of the Eocene Thermal Maximum on tropical vegetation are still unknown, but important for a full understanding of the climate and its effects on biota during this unique time in earth's history. One the best tools to study tropical vegetational changes are pollen and spores (Traverse, 1988). Pollen and spores provide a more continuous record of vegetational change than can be had from megafossils, particularly in tropical areas where megafossil plant remains are usually not well preserved. Large climatic variations in terrestrial tropical environments could lead to changes in vegetation that would be recorded by the fossil record of pollen and spores.

In the present study the palynomorph distributions and palynofacies across the late Paleocene-Eocene in the eastern Andes of Colombia are presented with the aim of producing high-resolution biostratigraphy, proposing sequence stratigraphy models for the area, and identifying any changes in pollen and spores diversity across the Eocene Thermal Maximum.














CHAPTER 2
OBJECTIVES



This project was undertaken to analyze the palynological biostratigraphic

distribution and sequence stratigraphy of three Paleogene sections in the Eastern Andes of Colombia (Fig. 3-1). The main objectives of this study were:

1. To complete a detailed taxonomic analysis of palynomorphs present in these
sections.

2. To build a high resolution biostratigraphic framework for the late PaleoceneEocene interval based on the occurrence and abundance of these palynomorphs.

3. To use palynofacies, palynomorph paleoecology, and lithofacies to propose a
preliminary sequence stratigraphy model for each section.

4. To analyze the various patterns of sporomorph (pollen and spores) diversity
throughout the middle Paleocene-Eocene of the Eastern Andes of Colombia.
These assemblages also were compared to palynofloras in Central America, U.S.
Gulf Coast, and tropical Africa during the Paleocene-Eocene.


4















CHAPTER 3
MATERIALS AND METHODS



Three stratigraphic sections were studied in the Eastern Andes of Colombia (Fig. 3-1). The first section is located in the Lianos Foothills, along Piialerita creek near Sabanalarga, 730 1' W - 40 54' N, where the Paleogene sequence comprises, from older to younger, the Barco-Cuervos Group (180 m), the oil-rich Mirador Formation (70 m), and the San Fernando Formation (300 m). The second section occurs in the eastern middle Magdalena Valley, along the Rio Negro river, near Uribe, 70 20N - 730 20W. The third section is located in the Catatumbo area, south of Cdcuta, Near La Donjuana, along the Regadera Creek, 72* 37' W - 70 42' N.

These sections were measured and described in detail (scale 1:100), recording major physical and biogenic sedimentary structures. The Jacob's staff method was used to measure the sections (Miall, 1984). This method allows for high resolution in sampling and detailed descriptions of stratigraphic sections. A staff was constructed of a

1.5m wooden rod, with a Brunton compass attached to the tip. The clinometer of the compass was preset at the measured structural dip of the strata in the section, thus the staff can be used to measured the stratigraphic thickness of the section. The staff was always positioned perpendicular to the bedding plane. A consecutive number was marked on the rock with red paint as the measuring of the section advanced upward in the section. These numbers were used as a reference system for describing the section and collecting samples for palynological processing. Rock samples were collected at five to ten meter intervals, for palynologic purposes, a reasonable sampling interval given the thickness of the analyzed sections (averaging 700m/section).


5








6


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CARIBBEAN
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AMERICA










- - x x egadera



Q .. ..- - - - -

e aderbea . -.... re.... u .n Te.
.. - . . . . . . . . .- - E e i e tr
.C .yA A A G . ... .



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0 ......4 ...












(modf*edfrtmDenouas Cany, Tea)
IL / Pifalerita.K
0 Erfcrtiaxy sedimentary

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<( I / E 1 oneous rocks

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Figure ~ ~ ~ ~ ~ ~ ~ ... 3..Golgcmp.fClo basown.hetresetos.tde

(modifed frm Deno and.ovey,1993)







7


The palynologic samples were prepared by the standard procedure of digesting sample in HF and HCl acids, separating organic matter by heavy liquids, and oxidizing with Schultz solution (Traverse, 1988). This method was specifically modified by Russ Harms from Global Geolab, who prepared most of the samples (Global Geolab 729B15th Street S.W., Medicine Hat, Alberta TIA 4W7, Canada). Twenty-five grams of sample were placed in a 250 ml polypropylene beaker along with a Lycopodium tablet. The Lycopodium tablets were used to have absolute concentrations of pollen per gram of sediment (Traverse, 1988). The specific weight for each sample was measured and recorded. A 10% solution of HCl was then added and left, generally overnight, allowing carbonates to dissolve. The HCl was decanted and washed 3 times with distilled water to remove remaining calcium ions that can flocculate when HF is added. Then, 70% HF was added to the sample. The sample was agitated for 4 hours until digestion was completed. The digested sample was poured into a 50 ml. polypropylene test tube and centrifuged for five minutes at 2000 rpm. The top 3/4 was then decanted, and distilled water was added while vortexing and the sample was centrifuged for two minutes. Distilled water was added until the solution was neutral. The next step consisted of adding 5 ml of Darvan, vortexing while adding distilled water and centrifuging for one minute at 2000 rpm. This washing/centrifuging was repeated until the fine clastic material was removed (3 or 4 times). A few drops of concentrated HCl were added for a better heavy liquid separation, vortexing while adding water and centrifuging for 4 minutes. The heavy liquid separation was done using ZnBr2 (gravity 2.0). Twenty-five ml of ZnBr2 were added to the sample, which was then vortexed thoroughly. The test tube was placed in an ultrasonic bath for ten seconds. Samples were allow to sit for ten minutes before centrifuging for 15 min. at 2000 rpm. The floating part was then poured off into another 50 ml tube, and washed and centrifuged three times for 2 min. at 2000 rpm. The residue was then transferred to a 20 ml glass tube and a first slide for palynofacies analysis was made. The residue was examined for the amount of oxidation







8


required. Three rrd of Schultz solution were poured in the tube with the residue, vortexed, and placed in a hot water bath for 4-12 min. Schultz was removed and the samples washed three times until the solution was neutral. A 10% NH40H solution was then added and placed in a hot water bath for 2 minutes. The sample was washed and centrifuged three times, was then sieved using a 7um nitex screen cloth. The sieved fractions were pipetted off and mixed in one drop of polyvinyl alcohol with a glass stirring rod. When the polyvinyl was dry, one drop of clear casting resin was added and the coverslip was turned and sealed. Permanent curing occurred in one hour.

A Carl Zeiss light microscope (Scope 2, #4311267, Paleobotany Laboratory, Florida Museum of Natural History) was used for palynologic analyses. At least one complete oxidized slide per sample was scanned with a 40x Zeiss planapochromatic objective and 300 palynomorphs per slide were counted when possible. Examination of the fossil taxa was done using a 100x Zeiss oil immersion planapochromatic objective. Slides are deposited in the Paleobotanical collection of the Florida Museum of Natural History.

Identification was done through comparison with published photographs and

descriptions, and the holotype material in the palynological collections of University of Amsterdam (Holland), Petrobras in Rio de Janeiro (Brazil), and Pedevesa in Caracas (Venezuela). I attempeted to consult the holotypes of the collections of Enrique Gonzalez in Venezuela and Gustavo Sarmiento in Colombia. However, these collections could not be observed because they are poorly preserved and inaccessible (Gonzalez, personal communication), and have been misplaced in the Ingeominas, Bogoti (Sarmiento, personal communication). Many of the holotypes I observed were badly damaged, especially those described before 1970, and I had to rely on the published descriptions and photographs.

Published papers on the U.S. Gulf Coast, Central America and tropical Africa were used as the main sources of the comparative study between the Paleogene of Gulf







9


Coast, Colombia, and Africa Palynoflora of northern South America was compared with assemblages from U.S. Gulf Coast, Central America and tropical Africa (Van HoekenKlinkenberg, 1966; Germeraad et al., 1968; Elsik, 1968a,b, 1978; Graham and Jarzen, 1969; Srivastava, 1972; Tschudy, 1973; Elsik, 1974; Elsik and Dilcher, 1974; Adegoke and Jan du Chene, 1975; Potter, 1976; Graham, 1977, 1985, 1993, 1995; Jan du Chene and Salami, 1978; Salard-Cheboldaeff, 1978, 1979, 1990; Jan du Chene et al., 1978a,b; Frederiksen, 1980; Martinez-Hernandez et al., 1980; Potter and Dilcher, 1980; Medus, 1982; Tomasini-Ortiz and Martinez-Hernindez, 1984; Mebradu et al., 1985; Salami, 1985; Schrank, 1987; Frederiksen, 1988; Ventatachala et al., 1988; Westgate and Gee, 1990; Oloto, 1992; Awad, 1994; El Beialy, 1998).

A time-framework based on the stratigraphic distribution of palynomorphs was

developed, using graphic correlation (Shaw, 1964; Edwards, 1984; Edwards, 1989). This is a method of correlating fossil occurrences based on interpretation of graphic plots of first and last appearances of taxa. This is a powerful method because it does not assume a priori that first and last appearances of chosen taxa are synchronous, as the traditional biostratigraphic zonations do. It also allows the production of high-resolution chronostratigraphic frameworks (Pasley and Hazel, 1995; Jaramillo and Oboh, 1999). The two most complete sections were plotted against each other and last and first appearances of all taxa presented in both sections were then compared and plotted (see Chapter 5). A line of correlation was then plotted. The ranges of the taxa were compared with the correlation line and extended up and down section when necessary producing a Composite Section. This Composite Section was then compared with additional sections in the same way. The process was repeated several times until the range of each taxon was stable and did not extended up or down anymore. The final result was a Composite Section that contained the longest range possible for each taxon. This method, however, tends to artificially extend taxon ranges, but this artifact is usually balanced by the variations in sample spacing and probability of finding particular taxa in all possible







10

samples (Edwards, 1984). The units of this Composite Section are composite units that represent time. They were then calibrated against the geologic time table using foraminiferal datums and radiometric datings.

Palynofacies analyses were only undertaken with non-oxidized slides. The oxidation process alters the natural colors of dispersed organic matter (palynodebris) and destroys certain organic matter types, such as structureless amorphous material (Traverse, 1988). At least 300 organic particles were counted per slide. In the absence of a standard palynofacies classification system, one adapted from Lorente (1986), Van Vergen et al. (1990), Oboh (1992), and Jaramillo and Oboh (1999) was used This system classifies dispersed organic matter based on morphological differences seen under a light microscope. The classification scheme is outlined below (see also Table 3-1). a. Aquatic organic matter that comprises the following:

a.1 Structureless amorphous material. They are gel-like and exhibit a "clotted"

appearance (Tyson, 1995).

a.2 Dinoflagellates and foraminiferal wall linings. Most fossil dinoflagellate cysts

indicate marine environments (Evitt, 1985). b. Terrestrially derived material that comprises:

b. 1 Structureless material

b. 1.1 Resins. Unstructured amber-color fragments.

b. 1.2 Black debris. Opaque particles without internal structure, and usually angular

shape. Sometimes called charcoal, black wood, or inertinite.

b. 1.3 Yellow-brown material. Structureless particles of yellow to light brown

color. This material could be attributable to highly degraded herbaceous material

b. 1.4 Black-brown material. Unstructured dark brown material, which could be

attributable to highly degraded woody material.

b.2 Structured material:







I1


b.2.1 Cuticles. Cuticles are extra-cellular layers covering the epidermis of higher

plants. Well preserved showing clear structure of epidermal cell outlines.

b.2.2 Plant Tissue. This group includes all kinds of plant tissue material, with the exception of cuticles and well-preserved woody material. Collenchyma and

parenchyma cells are included in this group.

b.2.3 Woody material. Particles with brown color, sharp angular edges and

discernible cellular structure.

b.2.4 Pollen and spores.

b.2.5 Fungi. This group includes all fungal remains such as hyphae, fruiting

bodies, and fungal spores.

Fluorescence was used for distinguishing between amorphous marine and degraded terrestrial organic matter. Marine amorphous is fluorescent, while the terrestrial amorphous is not fluorescent (Lorente, 1986).

Palynofacies data were analyzed using multivariate statistical techniques. A Euclidean-distance cluster analysis with average linkage was performed on the palynodebris percentage data and used to develop a palynofacies model, which was then correlated with changes in depositional environments. The Euclidean distance is especially designed to work with continuous or ratio scales (SYSTAT, 1992). Moreover, the linkage averages all distances between pairs of objects in different clusters and decides how far apart they are (Sokal and Michener, 1958).

Paleoecological analysis of palynomorph abundace distribution was done using

multivariate statistical techniques. Other methods as the Nearest Living Relative are very difficult to apply with pollen and spores in pre-Oligocene sediments (Traverse, 1988), although with a few exceptions (e.g., Spinizonocolpites pollen that is a close relative of extant Nypa, a mangrove palm of South East Asia, Germeraad et al., 1968). The use of multivariate statistical techniques such as Principal Component Analysis, Multidimensional Scaling, or Cluster Analysis relies on the basic assumption that







12


Table 3-1. Organic matter classification (adapted from Lorente 1986; Van Vergen et al ., 1990; and Jaramillo and Oboh, 1999).


Category Palynodebris Description
Aquatic Structureless amorphous Gel-like and exhibit a "clotted" appearance (Lorente, 1986) (structureless material
Aquatic Dinoflagellate cysts and Marine microphytoplankton and chitinous (Structured) foraminiferal wall linings internal linings of foraminifera; linings usually spirally-coiled

Terrestrial Resins Unstructured amber-color fragments normally
(Structureless) derived from stem tissues of gymnosperms
Black debris Opaque particles without internal structure;
have sharp angular edges or are lath-shaped; called black wood, charcoal and/or inertinite by several workers Yellow-brown fragments Structureless particles of yellow to light brown
color attributed to highly degraded herbaceous material Black-brown fragments Unstructured dark brown material, which is attributed to highly degraded woody material
Terrestrial Cuticles Cutin layer covering the epidermis of higher plants;
(Structured) well preserved and showing epidermis outline
Plant Tissue This group includes all other herbaceous
material, with the exception of cuticles; collenchyma and parenchyma are included here Woody material Brown particles with sharp angular edges
and discernible cellular structure
Pollen and spores Spores belonging to pteridophytes and pollen of
gymnosperms and angiosperms
Fungi This group includes all fungal remains, such as
hyphae, mycelia and non-embryophitic spores







13


pollen/spores that co-occurred in the same samples lived in similar environments, and that statistical parameters evaluate how strong a given co-occurrence is. This approach allowed testing of previous hypotheses for specific paleoenvironments. In addition it provided new hypotheses of palynomorph-environment relationships that can be tested in future studies.

The choice of which multivariate analysis to perform on any dataset depends upon the structure and noisiness of the data, the specific question being addressed, and the philosophy behind the study (Kovach, 1989). While considering a problem similar to the one being addressed in this study, Kovach (1989) analyzed a noisy and non-normal dataset, to relate species distribution to a terrestrial-marginal marine gradient, as well as to infer what groups characterized each environment. He found that the best method, which provides an unambiguous answer to the question (Pielou, 1984), was the Spearman rank-order coefficient performing a multidimensional scaling (MDS) analysis.

Spearman is a non-metric, quantitative similarity measure in which correlations are made based on the rank-order of the abundances rather than absolute values. Thus, variations in abundance due to noisy data or closure effect do not strongly affect this coefficient (Kovach, 1989) as with metric coefficients. It is effective in paleoecological studies because it places more weight on elements that are farther apart, while close ranks have little affect on the correlation (Sokal and Rohlf, 1981). Multidimensional scaling (MDS) is a multivariate statistical technique that is designed to construct a "map" showing the relationships between a number of objects, given only a table of distances between them (Manly, 1994). It makes no assumption of normality or linearity of the data (Kovach, 1989). It bases the ordination on the rank-order of the elements of the similarity matrix, rather than their absolute values. The basic assumption is that the greater the similarity between two objects, the closer they should be to each other in the ordination (Kovach, 1989). A value, called stress, measures the fitness of ordination to original similarities, the lower the value the fittest ordination. This method requires in







14


advance the number of dimensions to be used. Using the wrong number of dimensions, however, can distort the results, but generally using 2 or 3 dimensions show little distortion of this sort (Kendel and Orlocci, 1986).

MDS can identify major terrestrial-marginal marine gradients along the first and second axes, and seems to be least vulnerable to distortion from high beta diversity, nonnormality, and non-linearity (Kovach, 1989). In this study, MDS analysis was performed on a subset of data from the original distribution range charts. Palynomorphs with high abundances and those with recognized paleoenvironmental significance were selected for this analysis.

Sequence stratigraphic analyses for each section involved the integration of

palynofacies, palynomorph paleoecology, and lithological data. They were combined to identify major depositional environments for the three sections. Key surfaces, (maximum flooding surfaces, sequence boundaries, and transgressive surfaces) were identified based on the stacking patterns of interpreted sedimentary environments. Then, systems tracts and sequences were recognized. Because of the limited number of proposed sections, this study was not intended to reconstruct a regional geometry for study areas. Rather, the main goal in proposing a sequence stratigraphic study was to provide a hierarchical framework of depositional environments, that could be used to recognize major relative sea level changes during the time interval studied. Sequence stratigraphy terminology and techniques followed that of Van Wagoner et al. (1990).

The suggestion by Rosenzweig (1995) of using the word "diversity" in its original meaning of denoting number of species (called richness in the literature) is followed in the analysis of pollen/spores diversity. Patterns of pollen and spores diversity were analyzed using several methods: Rarefaction, a method used to compare the diversity of different samples taking into account sampling density (Raup, 1975). Small number of species in a sample can be an artifact of the number of grains counted in the sample. Rarefaction is a method that addresses this problem. It is an interpolation technique







15


making it possible to estimate how many species would have been found had the sample been smaller than it actually was (Raup, 1975). In this form, diversity from small and large samples can be compared with each other. Rarefaction has several limitations: collections to be compared should be taxonomically similar, they must also be obtained by using standardized sampling and analytic procedures, they should derive from similar habitats (all from similar lithologies when possible), and rarefaction must be restricted to interpolation of values not greater than the number of individuals of the parent collection (Tipper, 1979). The hypothesis under test is that rarefaction curves being compared refer to collections drawn from same population (population of diversities, not species); the alternative hypothesis is that the populations differ in their diversities (Tipper, 1979). Two populations composed of different species, then, could have similar rarefaction curves indicating that their diversities are similar. Rarefaction curves were calculated with the Rarefaction calculator developed by C. Krebs and J. Brzustowski (http://www.biology.ualberta.ca/jbrzusto/rarefact.html #Top) using the Hurlbert formulae to calculate number of species and Simberloff formulae to calculate the variance.

Bootstrap was used to determine the average of number of species/sample for

Paleocene and Eocene strata regardless the number of observed samples. Bootstrapping constructs estimates of frequency distributions for use in conducting statistical tests (Gilinsky, 1991). The mean diversity was calculated for a number of samples randomly selected with replacement from two datasets: seven samples from the Paleocene and 13 from the Eocene. This procedure was repeated 4999 times, and then average and confidence intervals for each time interval were calculated and compared. This analysis was done in MetaWin 1.0 with the help of Ricardo Holdo (University of Florida).

The range-through method (Boltovskoy, 1988) was used to estimate standing

diversity. This method assumed that a taxon is present in a sample if the taxon is present in samples below and above the sample examined. This method takes into account facies-related fossils and differences in capture probability for each taxon. The method







16

underestimates diversity for intervals at the beginning and end of a section, since there are not more samples that allow to extend ranges of rarer species (Boltovskoy, 1988).

The overall floral similarity throughout the section was observed using detrended correspondence analysis (DCA) developed by Hill and Gauch (1980). The ordination was performed on the presence-absence data that already had range-through extensions. Samples with less than 20 grains were eliminated from analysis. DCA summarizes variation in the composition of the assemblages in a small number of dimensions (Wing, 1998). This method assumed that cases come from a gradient in which different variables (in this case taxa) characterize different parts of the gradient making it particularly well suited for distinguishing single, major gradients in the first axis (Kovach, 1989). DCA analysis were performed in MVSP 3.0 statistical software developed by Warren Kovach (http://www.kovcomp.co.uk/mvsp/).

The unbiased Simpson index (SI=X(ni(ni-1)/N(N-1)), N=number of individuals in sample, ni=number of individuals of species i in the sample) was calculated to estimate underlying diversity independently of sample size (Rosenzweig, 1995). This index is free from influence of size of sample, it is adequate to estimate diversity of small samples, and when used as -Ln(SI) it increases as the number of species does (Rosenzweig, 1995). This index was calculated using MVSP 3.0 statistical software. Palynomorphs other than pollen and spores were excluded from all the analysis.















CHAPTER 4
REGIONAL GEOLOGICAL SETTING



Colombian geology has been complicated by uplift attributed to the Andean

orogeny that began during the late Cretaceous and was most active during the Pliocene (Van der Hammen et al., 1973). In general, sedimentary rocks comprise 70% of all the rocks in Colombia. Forty percent of the outcropping sedimentary strata are Cretaceous, approximately 55% are Tertiary and Quaternary, while 5% are Paleozoic, Triassic and Jurassic (Etayo-Serna et al., 1983). The sedimentary rocks can be found in ten tectonostratigraphic provinces (Etayo-Serna et al., 1983) that can be seen in Figures 3-1 and 4-1. Paleozoic sedimentary and metamorphic rocks, Triassic red beds and marine limestones, and Jurassic tuffs constitute the basement onto which Cretaceous rocks onlapped (Cediel et al., 1981). The late Jurassic-Cretaceous sea first inundated the northwestern Andean Basin possibly through a western corridor situated in the area that is now Central Colombia at the latitude of Bogotd during the Titonian-Berriasian. Subsequently this sea extended into most of southern and northern Colombia (Etayo-Serna et al., 1976). Cretaceous facies have been interpreted as representing marine environments of deposition, especially during the Turonian to Campanian interval (Etayo-Serna, 1979; Barrio and Coffield, 1992). Tertiary rocks accumulated in alluvial plain to littoral environments (Etayo-Serna et al., 1983) with the exception of the marine strata of the Atrato Basin and Lower Magdalena Valley (Galvis, 1980; Duque Caro, 1990). Colombia has undergone a complex history of compressional tectonic events that have produced a mix of superimposed structures (Dengo and Covey, 1993). The Eastern Cordillera (Figs. 3-1 and 4-1) was uplifted throughout the Tertiary with a late intense pulse during the Pliocene-Pleistocene (Van der Hammen et al., 1973), and is bounded by


17







18


thrust faults systems on its eastern and western margins. Eastern faults dip westward (Guaicaramo thrust system) and western faults dip eastward (Honda-Bituima thrust system), thus structurally creating a large "pop-up" feature that uplifted the Eastern Cordillera (Irving, 1975).

Colombian stratigraphic nomenclature has been complicated by the fact that several authors and oil companies have used different names for the same lithostratigraphic units, or the same name for different lithostratigraphic units (Montes et al., 1993). A recompilation of published information (Montes et al., 1993) has revealed that the lack of field data and the disorder in stratigraphic nomenclature have resulted in weak tectono-stratigraphic interpretations. These inconsistencies have made regional interpretations inaccurate or suspect when based on the literature. In this study, the stratigraphical nomenclature proposed by the Colombian Stratigraphical Lexicon (Porta, 1974) is followed.








19


Tectonostratigraphic provinces

1. Atrato
3 2. Cauca
3. Lower Magdalena Valley
4. Cesar
5. Middle Magdalena Valley 6. Upper Magdalena Valley
7. Eastern Cordillera
8. Catatumbo
9 9. Llanos Foothills
10. Llanos-Amazon 11. Non-sedimentary rocks




to1


Figure 4-1. Sedimentary tectono-stratigraphic provinces of Colombia. The sections studied are in terranes 5, 8, and 9 indicated by dotted pattern (After Etayo-Serna, 1983).















CHAPTER 5
BIOSTRATIGRAPHY



Biostratigraphy is a very important for understanding Colombian geology because rocks are rarely well exposed, and structural geology is very complex due to the interaction of the Caribbean, South America and Nazca plates during the last 150 million years. Rapid and dramatic facies and thickness changes across faults are frequent, and correlation of formations requires an excellent biostratigraphic control.

The most important, and very often the only, biostratigraphic tools in Tertiary sediments in the majority of Colombia are palynomorphs (mainly pollen and spores). Intense palynological work, mostly related to oil and coal exploration, has been done for the past 35 years. Unfortunately, not much work has been published especially for Paleogene sediments.

One of the fundamental elements for producing a detailed biostratigraphic

framework is a comprehensive understanding of pollen and spores taxonomy. A large percentage (-50%) of morphotypes described for Paleogene of Northern South America (see Table 5-1) lack detailed descriptions and good photographic records. In order to solve this problem, I visited the most important palynological collections of neotropical fossil pollen and spores that are available and still store some Paleogene holotypes (Petrobras in Rio de Janeiro, Pedevesa in Caracas, and University of Amsterdam in Amsterdam). Other collections, such as the one containing the 45 holotypes of Gonzalez (1967), were damaged and no longer useful (E. Gonzalez, personal communication). Others could not be found and possibly are already spoiled (most of Van der Hammen's holotypes of his 1955 to 1966 papers), and others are not available to the public or are not curated (Sarmiento, 1992).


20







21

In the Appendix A I present a detailed taxonomic analysis of 300 pollen, spores, and dinoflagellate species, that will be used in the biostratigraphic analysis.

Biostratigraphic ranges were analyzed using graphic correlation (see Chapter 3 for a more detailed description of this method). This approach is especially useful with pollen and spores because it allows an objective analysis of taxon range distributions. Phytogeography, especially in tropical regions where many species tend to have restricted ranges, would affect the use of traditional biostratigraphic zones. For example, there is a zone named Spinizonocolpites baculatus, defined by Muller et al. (1987) for the lower Paleocene of northern South America. The base of this zone is defined by the first occurrence of S. baculatus and the top by the last occurrence of S. baculatus. However, S. baculatus has long been recognized as related to Nypa, an extant mangrove palm living in South East Asia (Germeraad et al., 1968); therefore, S. baculatus would be restricted to lower coastal plain and estuarine facies. Fluvial sediments accumulated during the lower Paleocene would be unlikely to contain S. baculatus. Therefore, following the biostratigraphic zone approach, lower Paleocene strata would be "lacking" in fluvial sections because the pollen zone is absent, and an unconformity would be postulated. Probably, many of the "unconformities" that have been registered in Colombia strata (e.g., see Dengo and Covey, 1993) are an artifact of plant biogeography rather than time gaps. Graphic correlation approach accounts for facies changes and does not assume a priori that a particular taxon is a marker for any time interval. It also allows to use whole assemblages rather than "index" taxa and test hypothesis on range distributions. Graphic correlation becomes more robust as more information of different sections is added into the analysis. Finally, graphic correlation is more objective and relies less on personal opinion as traditional biostratigraphic zonations do.







22


Previous Studies

As far as can be determined thirty-three papers have been published on the Paleogene palynology of northern South America including Colombia, Venezuela, Guyana, and Brazil (Van der Hammen, 1954; Kuyl et al., 1955; Norem, 1955; Van der Hammen, 1956, 1957a,b, 1958; Garcia, 1958; Paba-Silva and Van der Hammen, 1958; Sole de Porta, 1961a,b, 1963; Porta and Sole de Porta, 1962; Van der Hammen and Wymstra, 1964; Leidelmeyer, 1966; Van der Hammen and Garcia, 1966; Gonzalez, 1967; Germeraad et al., 1968; Schuler and Doubinger, 1970; Sole de Porta, 1971; Wijmstra, 1971; Doubinger, 1973; Regali et al., 1974; Doubinger, 1976; Duefias, 1980; Muller et al., 1987; Colmenares, 1988; Colmenares and Terin, 1990, 1993; Sarmiento, 1992; Guerrero and Sarmiento, 1996; Rull, 1997b, 1998) All these papers, the majority of which were published before 1971, focused only on pollen and spores. Seventeen of them presented pollen/spores of Paleocene strata, five studies looked at Eocene strata, and five Oligocene strata. Only three of these studies provided measured stratigraphic sections with palynomorph range distributions. The publications listed above have yielded 339 taxa identified from Paleogene strata of northern South America including Brazil, Guiana, Venezuela, Peru, Ecuador and Colombia (Table 5-1). A comparison with living taxa have been attempted for just 55 of them. This information is summarized in Table 5-2, and Figure 5-1.

Several zonation schemes based on pollen and spores have been proposed for the Paleocene-Eocene of northern South America (Van der Hammen, 1957a, b; Leidelmeyer, 1966; Gonzalez, 1967; Germeraad et al., 1968; Regali et al., 1974; Muller et al., 1987). However, only two (Germeraad et al., 1968; Regali et al., 1974) offered some independent justification for the proposed age assignments.

Van der Hammen (1957 a, b; 1958) and his Holland school (Leidelmeyer, 1966; Gonzalez, 1967) were the precursors of palynological studies of Tertiary strata in northern South America. They used pollen/spores fluctuations (a pollen diagram) as a













Paleoc. Eocene Oligocene Miocene Q








a- a


-4 4. 4'4*41


~.h.


Family (genus, species) Order Major Clade

Annonaceae (Proxapertites humberfoides) Magnoliales ,"Magnoliid complex"
Proteaceae (Proreacidites dehaani) Proteales Basal tricolpates"I


Ulmaceae (Ulmoideipites krempii) Betulaceae (Alnus verus)


Caryocaraccae (Retisyncoporites angularis) Phyllanthoideae(Retitricolporites irregularis) Euphorbiaceae roLonoidm (Psilate colporiles operislakn) valphigiaceae (Perisyncolporites pokornyi)


Fabaceae (Striatricolpites calatumbus
IAarRocolporitles vanwiihei)


Rosales Fagales


Malpiguiales


Fabalcs


1-


Eurosids I


Crohlrnae


- I I I 11 N~yciaginaceae (magnapenporites spinosus) I yop yes_1__.7 ___


Malvaceae (Retritricolporites guianensis)
(Bombacacidites annae) (Echiverivorites estelae)


Lythraceae (Verrutricolporites rotundiporus) Rhizophoraceae (Zonocostites ramonae) Myrtaceae (Syncolporites lisamae) Onagraceae (Jussitriporites ondulatus)


Pellicieraceae (Psilatricolpories crassus)


Convolvulaceae_(Perfotricolpites digilatus)


Acanthaceae (Multiaerolitesformosus)


Asteraceae (Echitricolporites spinosus)


Poaceae (Monoporopollenites annulatus)


Arecaceae (Spinizonocolpites echinarus)
(Racemonocolpites racematus)


Malvales


Myrtales


Eurosids II


- Ericales I


I.


4


Solanales


Lamiales


4 4


Asterales


Euasterids I


Euasterids II


C,,

2-.


-~ .4 '-.4-


Poales


Arecales


Commelinanae


0


Figure 5-1. Range chart for selected angiosperm fossil pollen in northern South suprageneric classification after APG, 1998 and Judd et al., 1999)


America (modified from Muller, 1981,


I


...,.., ...,


C h ll l








24


Table 5-1. Pollen and spores named from the Paleogene of northern South America


taxa
Anacolosidites luteoides Annutriporites iversenni Arcotriporites asteroides Baculamonocolpites multispinosus Bacumorphomonocolpites tausae Bacustephanocolpites stereos Bombacacidites annae Bombacacidites brevis Bombacacidites ciriloensis Bombacaciditesfoveoreticulatus Bombacacidires soleformis Brevitricolpites variabilis .Buttinia andreevi Cicatricosisporites baculatus Cicatricosisporites cirae Cicatricosisporites colombiensis Cicatricosisporites cristatus Cicatricosisporites cundinamarcensis Cicatricosisporites dorogensis Cicatricosisporites radiatus Cicatricosisporites tabacensis Clamonocolpites terrificus Classites capucinii Clavainaperturites cordatus Clavamonocolpites microclavatus Clavastephanoporites ambigens Clavatricolpites gracilis Clavatricolporites leticiae Clavatriletes disparilis Colombipollis tropicalis Crassiectoapertites columbianus Crassitricolporites brasiliensis Crassitricolporites costatus Cricotriporitesfragilis Cricorriporites guianensis Cricotriporites operculatus Cristatricolpites analemae Crototricolpites americanus Crototricolpites annemarie Crusafontites grandiosus Cteniliphonidites costatus Ctenolophonidites lisamae Curvimonocolpites inornatus Cyclusphaera euribei Divisisporites enormus Duplotriporites ariani Echimonocolpites coni Echimonocolpites densus Echimonocolpites protofranciscoi Echimonocopites ruedae Echimorphomonocolpites gracilis Echimorphomonocolpites solitarius Echinatisporis minutes Echinoidites problematicus Echiperiporites akanthos Echiperiporites estelae


Author
Cookson and Pike, 1954 (Van der Hammen, 1954) Gonzalez, 1967 Gonzalez, 1967 (Van der Hanmen, 1954) Sole de Porta, 1971 Sole de Porta, 1971 Gonzalez, 1967 (Van der H ammen, 1954) Germeraad et al. , 1968 (Duenas, 1980) Muller et al. , 1987 Muller eta! ., 1987 Muller eta! ., 1987 Muller et al ., 1987 Gonzalez, 1967 Boltenhagen, 1967 Regali, Uesugui, and Santos, 1974 Kedves and Sole de Porta, 1963 Kedves and Sole de Porta, 1963 Regali, Uesugui, and Santos, 1974 Kedves and Sole de Porta, 1963 (Potonie and Gelletich, 1933) Kedves, 1961
Krutzsch, 1959 Kedves and Sole de Porta, 1963 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Muller et al ., 1987 Leidelmeyer, 1966 Gonzalez, 1967 Leidelmeyer, 1966 Regali, Uesugui, and Santos, 1974 Sarmiento, 1992 Duenas, 1980 Herngreen, 1972 Sarmiento, 1992 Van Hoeken-Klinkenberg, 1966 Leidelmeyer, 1966 Van Hoeken-Klinkenberg, 1966 Leidelmeyer, 1966 Wijmstra, 1971 Leidelmeyer, 1966 Sole de Porta, 1971 (Van Hoeken-Klinkenberg, 1964) Van Hoeken-Klinkenberg, 1966 (Van der Hammen and Garcia, 1966) Germeraad et al. , 1968 Leidelmeyer, 1966 Elsik, 1966 Pfug, 1953 Sarmiento, 1992 Sarmiento, 1992 Gonzalez, 1967 Sarmiento, 1992 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Gonzalez, 1967 Gonzalez, 1967 Van der Kaars, 1983 Gonzalez, 1967 Van der Hammen and Wymstra, 1964 Germeraad, Hopping, and Muller, 1968








25


Table 5-1--continued.


taxa
Echistephanoporites alfonsi Echitricolpites communis Echitricolpites polaris Echitriletes muelleri Echitriporites guianensis Echitriporites nuriae Echitriporites triangulifornis Ephedripites multicostatum Ephedripites vanegensis Ericipires annularus Filtotriletes nigeriensis Foveodiporites guianensis Foveodiporites operculatus Foveostephanocolpites perfectus Foveostephanocolpites typicus Foveostephanocolporites liracostatus Foveorricolpites genuinus Foveolricolpites perforatus Foveotricolpites pomarius Foveotricolpires santanderianus Foveotricolporites caldensis Foveorricolporites crasiexinus Foveofricolporites marginatus Foveotricolporites voluninosus Foveotriletes margaritae Foveotriporires hammenii Gemmamonocolpites amnicus Gemmamonocolpites barbatus Gemmamonocolpites dispersus Gemmamonocolpites gemnatus Gemmamonocolpites macrogemmatus Gemmamonocolpites ovatus Gemmastephanocolpites asterofornis Gemmastephanocolpites gemmatus Gemmastephanoporites breviculus Gemmastephanoporites polymorphus Gemnatricolpites pulcher Gemmarricolpites vigdisae Gemmatricolporites berbicensis Gemmatricolporites divaricalus Hamulatisporites caperatus Heterocolpites paleocenica Hererocolpites paluster Inaperturopollenites cursis Incertiscabrites pachoni Incerturugulites carbonensis Jandufouria seamrogiformis Janmulleripollis pentaradiatus Jussitriporites undulatus Laevigatosporites catanejensis Leiotriletes guadensis Longaperrifes brasiliensis Longapertites circularis Longapertitesfossuloides Longapertites perforatus Longaperrites perforatus


author
Leidelmeyer, 1966 Regali, Uesugui, and Santos, 1974 Regali, Uesugui, and Santos, 1974 Regali, Uesugui, and Santos, 1974 Leidelmeyer, 1966 Duenas, 1980 Van Hoeken-Klinkenberg, 1964 Brenner, 1963 Van der Hammen and Garcia, 1966 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Wijmstra, 1971 Van der Kaars, 1983 Leidelmeyer, 1966 Leidelmeyer, 1966 Leidelmeyer, 1966 Gonzalez, 1967 Van der Hammen and Garcia, 1966 Van der Hammen and Garcia, 1966 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Gonzalez, 1967 Gonzalez, 1967 (Van der Hammen, 1954) Germeraad, Hopping, and Muller, 1968 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Sarmiento, 1992 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Muller, Giacomo, and Erve, 1987 Gonzalez, 1967 Leidelmeyer, 1966 Van der H ammen and Garcia, 1966 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer, 1966 Leidelmeyer, 1966 Leidelmeyer, 1966 (Van Hoeken-Klinkenberg 1964) Schrank, 1994 Van der Hammen and Garcia, 1966 Gonzalez, 1967 Sarmiento, 1992 (Van der Hammen, 1954) Sarmiento, 1992 Sarmiento, 1992 Germeraad, Hopping, and Muller, 1968 Di Giacomo and Van Erve, 1987 Gonzalez, 1967 Muller, Giacomo, and Erve, 1987 (Van Der Hammen, 1954) Sole de Porta, 1971 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Sarmiento, 1992








26


Table 5-1--continued.


taxa
L proxapertiroides var proxapertitoides L proxapertitoides var reticulatus L proxapertitoides var. reticuloides Longapertites vaneendenburgi Longitrichotomocolpites triangularis Magnaperiporites spinosus Magnastriatites grandiosus Magnatriporites abstractus Magnotetradites magnus Margocolporites vanwijhei Mauritiiditesfranciscoi var.franciscoi Mauritiiditesfranciscoi var. minutus M. franciscoi var. pahyexinatus Microfoveolatosporis skottsbergii Microfoveotriporites cretaceous Momipites africanus Monolitesferdinandi Monoporites annulatus Monoporites annuloides Monoporites parcus Papillamonocolpites splendedus Papillopolis partialis Perfotricolpites digitatus Perfotricolpites semistriatus Periretipollis spinosus Periretisyncolpites giganteus Perisyncolporites pokornyi Plicapollis arcii Polotricolporites concrerus Polotricolporites mocinnii Polotricolporites versabilis Polyadopollenites mariae Polypodiaceoisporites potonie Proteacidites dehaani Proteacidites miniporatus Protudiporites typicus Proxapertites cursus Proxapertitesfacetus Proxapertites humbertoides Proxapertires magnus Proxapertites minutes Proxapertites operculatus Proxapertites psilatus Proxapertites tertiaria Proxapertites verrucatus Pseudostephanocolpites perfectus Pseudostephanocolpites? verdi Psilabrevitricolpitesflexibilis Psilabrevitricolpites rotundus Psilabrevitricolporites annulatus Psilabrevitricolporites simpliformis Psiladiporites redundantis Psilamonocolpites ciscudae Psilamonocolpites grandis Psilamonocolpites huertasi Psilamonocolpites medius


author
Van der Hammen and Garcia, 1966 Van der Hammen and Garcia, 1966 Gonzalez, 1967
Germeraad, Hopping, and Muller, 1968 Gonzalez, 1967
Gonzalez, 1967
(Kedves and Sole de Porta, 1963) Duenas 1980 Gonzalez, 1967
(Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Germeraad, Hopping, and Muller, 1968 (Van der Hammen, 1956) Van Hoeken-Klinkenberg, 1964 Van der Hammen and Garcia, 1966 Van der Hammen and Garcia, 1966 (Selling, 1946) Srivastava, 1971 Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 (Van der Hammen, 1954) Sole de Porta, 1972 Van der Hammen, 1954 Gonzalez, 1967
Sarmiento, 1992 Gonzalez, 1967
Gonzalez, 1967
Gonzalez, 1967
Gonzalez, 1967
Legoux, Belsky, and Jardine, 1972 Keiser and Du Chene, 1979 Germeraad, Hopping, and Muller, 1968 Gonzalez, 1967
Gonzalez, 1967
Gonzalez, 1967
Gonzalez, 1967
Duenas, 1980
(Potonie and Gell, 1933) Kedves, 1961 Germeraad, Hopping, and Muller, 1968 Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 Regali, Uesugui, and Santos, 1974 (Van der Hammen, 1954) Sarmiento, 1992 Muller, Giacomo, and Erve, 1987 Duenas, 1980
(Van der Hammen, 1954) Van der Hammen, 1956 Sarmiento, 1992 Van der Hammen and Garcia, 1966 Sarmiento, 1992 Gonzalez, 1967
Gonzalez, 1967
Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 Sarmiento, 1992 Van der Kaars, 1983 Gonzalez, 1967
Sarmiento, 1992 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966








27


Table 5-1--continued.


taxa
Psilastephanocolpites adinos Psilastephanocolpites globulus Psilastephanocolpites maia Psilastephanocolpites marginatus Psilastephanocolpites verrucosus Psilastephanocolporites fissilis Psilastephanocolporites globulus Psilastephanocolporites variabilis Psilastephanoporites caribiensis Psilastephanoporites stellatus Psilasyncolporites parvus Psilatephanocolpites regularis Psilatricolpites acerbus Psilairicolpites brevis Psilatricolpites clarissimus Psilatricolpites colpiconstrictus Psilatricolpites micro verrucatus Psilatricolpites minutes Psilatricolpites operculatus var. mi Psilatricolpites palaeoceanica Psilatricolpites polaroides Psilarricolpites simplex Psilatricolpites solus Psilatricolpites undamarginis Psilatricolporites costatus Psilatricolporites crassus Psilatricolporites maculosus Psilatricolporites marginatus Psilatricolporites normalis Psilatricolporites obscurus Psilatricolporites operculatus P. operculatus var. medius Psilatricolporites optimus Psilatricolporites pachyexinatus Psilatricolporites transversalis Psilatricolporites triangularis Psilatricolporites vanus Psilatriletes martinensis Racemonocolpitesfacilis Racemonocolpites racematus Racemonocolpites racematus Racemonocolpites romanus Retibrevitricolpires catatumbus Retibrevitricolpites distinctus Retibrevitricolpites increatus Retibrevitricolpites relibolus Retibrevitricolpites triangulatus Retidiporites agilis Retidiporites botulus Retidiporites elongarus Retidiporites magdalenensis Retiheterocolpites tertiarus Retimonocolpites bernardii Retimonocolpites claris Retimonocolpites longapertitoides Retimonocolpites microreticulatus


author
Gonzalez, 1967
Van der Kaars, 1983
Leidelmeyer, 1966
Gonzalez, 1967 Gonzalez, 1967
Leidelmeyer, 1966
Van Hoeken-Klinkenberg, 1966
Regali, Uesugui, and Santos, 1974
Duenas, 1980
Regali, Uesugui, and Santos, 1974
Gonzalez, 1967
Van Hoeken-Klinkenberg, 1966
Gonzalez, 1967 Gonzalez, 1967
Van der Hammen and Wymstra, 1964
Van Hoeken-Klinkenberg, 1966
Sarmiento, 1992 Gonzalez, 1967 nutus Gonzalez, 1967
Van der H ammen and Garcia, 1966
Gonzalez, 1967 Gonzalez, 1967
Leidelmeyer, 1966 Leidelmeyer, 1966
Duenas, 1980
Van der Hammen and Wymstra, 1964
Regali, Uesugui, and Santos, 1974
Van der Kaars, 1983
Gonzalez, 1967 Gonzalez, 1967
Van der Hammen and Wymstra, 1964
Gonzalez, 1967 Gonzalez, 1967
Van der Kaars, 1983
Duenas, 1980
Van der Hammen and Wymstra, 1964
Gonzalez, 1967 Sarmiento, 1992 Gonzalez, 1967
(Van der Hammen, 1954) Gonzalez, 1967
Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967
Van Hoeken-Klinkenberg, 1966
Gonzalez, 1967
Leidelmeyer, 1966
Van Hoeken-Klinkenberg, 1966
Gonzalez, 1967
Leidelmeyer, 1966
Sarmiento, 1992
Van der Hammen and Garcia, 1966
Gonzalez, 1967 Gonzalez, 1967 Sarmiento, 1992 Sarmiento, 1992
Van der H ammen and Garcia, 1966








28


Table 5-1--continued.

taxa
Retimonocolpites splendidus Retimonocolpites tertiarius Retipollenites confusus Retistephanocolpires angeli Retistephanocolpites finalis Retistephanocolpites minutus Retistephanocolpites regularis Retistephanocolpites tropicalis Retistephanocolpites williamsi Retistephanocolporites festivus Retistephanoporites angelicus Retisyncolporites angularis Retisyncolporites aureus Refitricolpites absolutus Retitricolpites adeptus Retifricolpites adultus Reritricolpires agricaulis Retitricolpites amapaensis Refitricolpites antonii Retitricolpites bonus Retitricolpites brevicolpartus Retitricolpites cecryphalium Retitricolpites clarensis Retitricolpites colombiae Retitricolpites concilialus Retitricolpites constrictus Retitricolpitesfiorentinus Reritricolpites herrerae Rerirricolpites incisus Retitricolpites josephinae Retitricolpites kwakwanensis Relitricolpites magnus Retitricolpites maledictus Retitricolpites marginatus Retifricolpites maturus Retitricolpites microreficulatus Retitricolpites minurus Retitricolpites minutes Retitricolpites obtusus Retitricolpites ovalis Retitricolpites perdirus Retitricolpites perforatus Retitricolpites retiaphelis Retitricolpites reticulatus Retitricolpites saturum Retitricolpites simplex Retitricolporites amazonensis Retirricolporites cienaguensis Retitricolporites costatus Retitricolporites craceus Retitricolporites crassicostatus Retitricolporites crassicostatus Retitricolporites ellipticus Retitricolporites equaroriales Retitricolporites exinamplius Retitricolporitesfinitus


author
Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer, 1966 Gonzalez, 1967 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Duenas, 1980 Germeraad, Hopping, and Muller, 1968 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer, 1966 Regali, Uesugui, and Santos, 1974 Gonzalez, 1967 Gonzalez, 1967 Sarmiento, 1992 Leidelmeyer, 1966 Gonzalez, 1967 (Van der Hammen, 1954) Sarmiento, 1992 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Gonzalez, 1967 (Van der Hammen, 1954) Sarmiento, 1992 Leidelmeyer, 1966 Gonzalez, 1967 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Gonzalez, 1967 (Van der Hammen, 1954) Van der Hammen and Wymstra, 1964 Gonzalez, 1967 Pierce, 1961 Van Hoeken-Klinkenberg, 1966 Van der Hammen and Wymstra, 1964 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer. 1966 (Van der Hammen, 1954) Van der Hammen and Wymstra, 1964 Gonzalez, 1967 Gonzalez, 1967 Regali, Uesugui, and Santos, 1974 Duenas, 1980 Leidelmeyer, 1966 Gonzalez, 1967 Van der Hammen and Wymstra, 1964 Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 Gonzalez, 1967 Sarmiento, 1992 Gonzalez, 1967








29


Table 5-1--continued.


taxa
Retirricolporites irregularis
Retitricolporites marianis
Retitricolporites mariposus
Retitricolporites medius
Retitricolporites perpusillus Retitricolporites profundus Retitricolporites quadrosis
Retitricolporites saskiae
Retitricolporites squarrosus Retitriporites dubiosus Retitriporitesfedericii Retitriporites simplex Retitriporites tilburgii Retitriporites typicus Rugotricolpites oblatus Rugotricolporitesfelx Scabraperiporites asymmetricus Scabraperiporites nativensis Scabrastephanocolpites guaduensis Scabrastephanocolpites scabratus Scabrastephanocolpites vanegensis Scabratricolpites angelicus Scabratricolpites thomasi Scabratricolpites tibialis Scabratricolporites platanensis Scabratriletes globulatus Scabratriporites moderatus Scabratriporites redundans Scabratriporites simpliformis Semitectotriporites gratus Spinozonocolpites baculatus Spinozonocolpites echinatus Spinozonocolpites intrarugulatus Spinozonocolpites sutae Spironsyncolpites spiralis Spirosyncolpites clavatus Stephanocolpites costatus Striatricolpites catatumbus Striatricolpites minor Striatricolpites semistriatus Striatricolporites agustinus Striatricolporites meleneae Striatricolporites pimulis Striatricolporites tenuissimus Striatriporites nigeriensis Syncolporites lisamae Syncolporites marginatus Syncolporites poricostatus Syncolporites rugucostatus Syndemicolpites tipicus Terradites umirensis Tricolpites rubini Ulmoideipires krempii Venezuelites globoannulatus Verrucatosporites usmensis Verrustephanocolpites verrucatus


author
Van der Hammen and Wymstra, 1964
Gonzalez, 1967
Leidelmeyer, 1966
Gonzalez, 1967
Regali, Uesugui, and Santos, 1974
Gonzalez, 1967
Regali, Uesugui, and Santos, 1974
Gonzalez, 1967
Van der Hammen and Wymstra, 1964
Gonzalez, 1967 Gonzalez, 1967
Van der Kaars, 1983
Gonzalez, 1967 Gonzalez, 1967 Sarmiento, 1992 Gonzalez, 1967 Duenas, 1980 Regali, Uesugui, and Santos, 1974 (Van der Hammen, 1954) Sarmiento, 1992 Van der H ammen and Garcia, 1966 Van der H ammen and Garcia, 1966 Sarmiento, 1992 Sarmiento, 1992 Gonzalez, 1967 Duenas, 1980 Sarmiento, 1992 Gonzalez, 1967 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Gonzalez, 1967 Muller, 1968 Muller, 1968 Muller, Giacomo, and Erve, 1987 Sarmiento, 1992 Gonzalez, 1967 Gonzalez, 1967 Van der H ammen, 1954 Gonzalez, 1967 Wijmstra, 1971 Gonzalez, 1967 Gonzalez, 1967 Duenas, 1980 Leidelmeyer, 1966 Duenas, 1980 Van Hoeken-Klinkenberg, 1966 Van der Hammen, 1954 Van Hoeken-Klinkenberg, 1964 Van Hoeken-Klinkenberg, 1966 Sarmiento, 1992 Van Hoeken-Klinkenberg, 1964 Van der Hammen, 1954 Van der Hammen, 1954 (Anderson, 1960) Elsik, 1968b Muller, Giacomo, and Erve, 1987 (Van der Hammen, 1956) Germeraad et al. , 1968 Van der Hanmen and Garcia, 1966








30


Table 5-1--continued.

taxa
Verrutricolpites isolatus Verrutricolpiles unicus Verntricolpites verrubolus Verrutricolporites haplites Verrutricolporites rotundiporis Verrutriporites asymmetricus Wilsonipites margocolpatus Zlivisporis blanensis Zonocostites duquensis Zonocostiles ramonae Zonotricolpites lineaus Zonotricolpites variabilis


author
Leidelmeyer, 1966 Gonzalez, 1967 Leidelmeyer, 1966 Gonzalez, 1967 Van der Hammen and Wymstra, 1964 Regali, Uesugui, and Santos, 1974 Muller, Giacomo, and Erve, 1987 Pacltova, 1961 Duenas, 1980 Germeraad, Hopping, and Muller, 1968 Sarmiento, 1992 Sarmiento, 1992







31


Table 5-2. Botanical affinities for fossil sporomorphs from northern South America (After Van der Hammen 1954, 1956, 1957a,b; Sole de Porta, 1961a, b; Van der Hammen and Garcia, 1966; Gonzalez, 1967; Germeraad et al ., 1968; Muller et al. , 1987; Sarmiento, 1992). Dispersion centers after Gentry (1982), suprageneric classification after Judd et al . (1999)


FOSSIL SPOROMORPH PROBABLE BOTANICAL FAMILY FAMILY
AFFINITY DISPERSION
CENTER*
Alnipollenites verus Alnus Betulaceae L
Anacolosidites luteoides Anacolosa Olacaceae AZ
Cathedra
Ptychopetalum
Bombacacidites annae Bombax ceiba Bombacaceae AZ
B. rhodognaphalon
B. pubescens
Buttinia andreevi Unknown
Cicatricosisporites dorogensis Anemia Schizaeaceae
Mohria
Crassoretitriletes vanraadshooveni Lygodium microphyllum Schi zaeaceae Ctenolophonidites costatus Ctenolophon engleri Ctenolophonaceae
Ctenolophonidites lisamae Ctenolophon Ctenolophonaceae
Echiperiporites estelae Thespesia populnea Malvaceae ?
Hibiscus tiliaceus
Hibiscus rosa-sinensis Ipomoea phillomega Convolvulaceae AZ
Echitricolporites minutus Ambrosia Compositae AN
Crassocephalum
Iva
Xanthium
Echitricolporites spinosus Espeletia Compositae AN
Mikania
Pectis
Wedelia
Wulfia
Echitriporites trianguliformis Embothrium Proteaceae SA
Garnieria
Persoonia
Telopea
Florschuetzia trilobata Lagerstroemia flos-regina Lythraceae
F. levipoli Sonneratia alba
F. semilobata
Fenestrites spinosus Elephantopus angustifolia Compositae AN
Rolandiafruticosa
Vernonia canescens
Vernonia remotiflora
Foveotricolpites perforatus Extinct
Foveotriletes margaritae Lindsaya orbiculata
Ophioglossum falcatum
0. concinnuum







32


Table 5-2--continued.

FOSSIL SPOROMORPH PROBABLE BOTANICAL FAMILY FAMILY
AFFINITY DISPERSION
CENTER*
Grimsdalea magnaclavata Palm ty pe Palmae AZ
Heterocolpites paluster Melastomataceae AN
Jandufouria seamrogiformis Catostemma Malvaceae AZ
Jussitriporites undulatus Onagraceae S A
Longapertites perforatus Annonaceae AZ
Longapertites brasiliensis Annonaceae AZ
Magnastriatites grandiosuts Ceratopteris (fresh-water) Parkeriaceae Magnaperiporites spinosus Mirabilis N yctaginaceae
Margocolporites vanwijhei Caesalpinia Fabaceae
Adipera
Brasilettia
Haematoxylon
Mezoneuron
Poincianella
Mauritiidites franciscoi Mauritia Palmae AZ
Monoporites anulatus Poaceae ?
Multiareolites formosus Adhatoda Acanthaceae AN
Anisotus
Baloperone
Dianthera
Jacobinia
Justicia
Kolobochilus
Monechma
Rungia
Multimarginites vanderhammeni Sanchezia klughi Acanthaceae AN
Trichanthera gigantea
Pachydermites diederixi Svmphonia globultifera Guttiferae AN
Perfotricolpites digitatus Merremia glabra Convolvulaceae AZ
M. umbellata
Scaevola Goodeniaceae ?
Valerianella stenocarpa Caprifoliacea L
Perisyncolporites pokornyi Brachypteris Malpighiaceae AZ
Bunchosia
Hiraea grandifolia
Mascagnia
Stigmaphyllum
Tetrapterys
Proteacidites dehaani Guevina avellana Proteaceae SA
Proxapertites cursus Nvpa related
Proxapertites operculatus Nypa related
Astrocarium (sensu TVH) Palmae AZ
Psiladiporites minimus Artocarpus Moraceae AZ
Ficus
Sorocea







33


Table 5-2--continued.


FOSSIL SPOROMORPH PROBABLE BOTANICAL FAMILY FAMILY
AFFINITY DISPERSION
CENTER*
Retibrevitricolpites triangulatus Extinct

Retidiporites magdalenensis Banksia collina Proteaceae SA
Dryandra longifolia
Retistephanocolpites williamsi Ctenolophon parfivolius Ctenolophonaceae Retisyncolporites angularis Carvocar Caryocaraceae
Retitricolporites irregularis Ananoa oblongifolia Euphorbiaceae AZ
Pseudolachnostylis glauca
Retitricolporites saskiae ? Malvaceae AZ
Retricolporites guianensis Firmiania colorata Malvaceae
Hildegardia barteri
Glossostemon bruguieri Pterocymbium beccari Sterculia mexicana
Trichospermum
Spinozonocolpites baculatus Nypa fruticans Palmae AZ
Spinozonocolpites echinatus Stephanocolpites costats Tabenaemontana attenuata Apocynaceae AZ
Striansyncolpites zwaardi Cuphea Lythraceae L?
Striatricolpites caatumnbus Crudia Fabaceae sub. L
Anthonotha Faboideae
soberlinia
Macrolobium bifiliuntm Striatricolporites agustinus Anacardiaceae AZ?
Syncolporites lisamnae Myrtaceae
Verrucatosporites usmensis Stenochlaena palustris Pol ypodiaceae
Phlebodium aureum
Histiosperis incisa
Polypodium pectinatum P. triseriale
Verrutricolporites rotundiporis Crenea miaritima Lythraceae AZ
Zonocostites ramonae Rhizophora Rhizophoraceae AZ
Bruguiera
Ceriops
Carallia


* AZ: Amazon
AN: Andes
SA: Southern South America
L: Laurasia






34

proxy for climatic cycles that presumably have a chronostratigraphic value. This "pollen diagram" is based on coal samples from different areas in Colombia. Proportions of different elements such as Psilamonocolpites group, Mauritiidites group, Psilatriletes group, are then calculated and plotted along the stratigraphic sections. Abundance peaks of specific groups are assumed to represent vegetational changes due to regional climatic changes. Therefore, they assumed that these peaks have a chronostratigraphic value and can be used for correlation. The epochs and ages of the Tertiary are then positioned in the pollen diagram based on the changes of relative proportions of certain groups, assuming that climatic changes are correlated with epoch/age boundaries.

Van der Hammen (1958) correlates the base of each epoch to an arenite level. This biostratigraphic scheme is then used to date most of the Tertiary continental formations of Colombia and Guyana (Van der Hammen, 1957a, 1957b, 1958; Van der Hammen and Wymstra, 1964; Leidelmeyer, 1966; Gonzalez, 1967; Wijmstra, 1971). Many of those datings are still deeply rooted in Colombian stratigraphy and used for correlation and modeling purposes. However, there are many problems associated with this approach. First, there is a statistical artifact associated with Van der Hammen's pollen diagrams, which is called the "closed sum" (Moore et al., 1991; Kovach and Batten, 1994). Percentages of each sporomorph group were calculated by counting 200300 grains per sample, then, the results were normalized. This method, however, tends to produce artificial negative correlations, when a group (A) significantly increases its abundance in a sample, another group (B) automatically decreases its abundances, even though its real abundance did not change. Then, these negative correlations among Van der Hammen groups could be an artifact of normalization, and peaks of certain groups could be the product of a decrease in other groups. There is also the weak assumption that pollen production and dispersal is similar for all species and that all taxa have a regional distribution (Porta and Sole de Porta, 1962). Furthermore, coals, the main source of Van der Hammen's samples, generally have a unique and facies-restricted flora







35


that is unsuitable for biostratigraphic purposes (Traverse, 1988). Porta and Sole de Porta (1962) analyzed twenty-four samples in 12 stratigraphic meters of a Miocene section in Cundinamarca, and found that its pollen diagram could be easily correlated with zones A and B of a general pollen diagram for the Oligocene. This approach also does not use an independent data-set that can test the ages given by pollen groups, therefore circular reasoning is highly possible. In conclusion, correlation of "climatic cycles" deduced from the pollen record probably reflects similar ecological conditions rather than time lines, and should not be used as a tool for dating Tertiary rocks.

Germeraad et al. (1968) in a pioneer study proposed a number of palynological zones for tropical Tertiary sediments. The zones were based mainly on material from Nigeria, Venezuela, and Colombia. They used several planktonic foraminifera to correlate their palynological zones to the geologic time scale. The stratigraphic ranges of those foraminifera taxa are presented in Figure 5-2. Ranges are derived from Postuma (1971), Bolli and Saunders (1985), Tourmankine and Luterbache (1985) (T&L85), Bolli et al. (1994), and Robinson and Wright (1993). Taxa that are not in Figure 5-2, but were mentioned by Germeraad et al. (1968), correspond to those of local importance that are not commonly used for global correlation. The following are the palynological zones proposed by Germeraad and the foraminifera used to correlate them with the geologic time scale (unless actually cited, the publications in which the names first appeared are not listed in the References list). The list also include the geographic location where the foraminifera were recorded from:



1. Retidiporites magdalenensis zone Danian-Paleocene

Nigeria

lower part of zone: Danian

Globigerina compressa (now Planorotalites compressa (Plummer 1926) Tourmankine, and Luterbache 1985): upper Plb-top P3 (T&L85)











m-X




CD





o S00
CD


0




CD
0









CL


EOCENE


I 2


PA LEOCENE



2 -g




e I


Truncoromaloides rohri Lepidocyclina pustulosa

Nummulites striatoreticuila
Bulimina jacksonensis


---G~lobigerina ampliaperturi


Blow 1969
Berggren and
Van Couvering 1 Planorotalites compressa Globoconusa daubjergens Planorotalites pseudomen Morozovella acuta Morozovella velascoensis Morozovella acuta Morozovella velascoensis Morozovella formosaforn Globorotalia rex




Helicostegina gyralis


974

9

is

ardii









osa





Psilairicolporites b crassus zone :


P. operculatus
-R. guianensis
zoneR






tus


C. dorogensis ata zone o


0 I







37

G. daubjergensis (now Globoconusa daubjergensis (Bronnimann 1953) Toumarkine and Luterbacher 1985) middle Pla-top PId (T&L85) Nigeria

upper part of zone: Paleocene Globorotalia pseudomenardii (now Planorotalites pseudomenardii (Bolli 1957) Toumarkine and Luterbacher 1985) base P4-top P4 (T&L85) G. velascoensis (now Morozovella velascoensis (Cushman 1925) Toumarkine and Luterbacher 1985): base P4-lowest P6 (T&L85) G. acuta (now Morozovella acuta (Toulmin 1941) Toumarkine and Luterbacher 1985): upper P3--middle P6 (T&L85)



2. Retibrevitricolpites triangulatus zone Paleocene-early Eocene Colombia

lower part of zone: Paleocene Actinosiphon barbadensis



Nigeria

lower part of zone: Paleocene Globorotalia velascoensis (now Morozovella velascoensis (Cushman 1925) Toumarkine and Luterbacher 1985): base P4-lowest P6 (T&L85) G. acuta (now Morozovella acuta (Toulmin 1941) Toumarkine and Luterbacher 1985): upper P3-~middle P6 (T&L85)



Nigeria

upper part of zone: early Eocene Globorotalia formosa (now Morozovella formosa formosa (Bolli 1957) Toumarkine and Luterbacher 1985): upper P6-upper P8 (T&L85)







38


Globorotalia rex Martin 1943: G.rex zone to lower part of G. formosa/aragonensis zone (Postuma, 1971). This is equivalent to P6 zone.



3. Monoporites annulatus zone late early Eocene-middle Eocene. This zone in the Caribbean is subdivided in the Psilatricolporites crassus, Psilatricolporites operculatus, and Retritricolporites guianensis zones.

Nigeria

lower, middle and upper part of zone: late early Eocene-middle Eocene Cassigerinelloita amekiensis Stolk 1963



3a. Psilatricolporites crassus zone middle Eocene Venezuela

lower part of zone: early middle Eocene Linderina floridensis

Helicostegina gyralis Barker and Grimsdale, 1936: middle P6b/P9-middle P10/12, in lower part of Chapelton Formation Jamaica (Robinson and Wright, 1993). Authors probably refer to zones of Berggren and Miller (1988) that established Paleocene/ Eocene boundary in P6a/b boundary (P6a defined by LAD of M. velascoensis). Lepidocyclina sp. A



Venezuela

upper part of zone: late middle Eocene Helicolepidina spiralis form C in Van Raadshoven (1951). A larger foraminifera from Rio San Pedro fauna, Zulia, Venezuela. According to Van Raadshooven (1951), it occur in middle Eocene beds in Maracaibo area. Proposed age is based on co-occurrence with Pseudophragmina (Proporocyclina) cf. perpusilla (Vaughan), Ferayina coralliformis







39


Frizzell, and Lepidocyclina aff. Lepidocyclina peruviana-r. douvillei group, that are also larger foraminifera.



3b. Psilatricolpites operculatus and Retitricolpites guianensis zone late middle Eocene Venezuela

Helicolepidina spiralis Tobler. A larger foraminifera from Rio San Pedro fauna, Zulia, Venezuela. According to Van Raadshooven (1951), it occurs in middle Eocene beds in Maracaibo area. Proposed age is based on co-occurrence with Pseudophragmina (Proporocyclina) cf. perpusilla (Vaughan), Ferayina coralliformis Frizzell, and Lepidocyclina aff. Lepidocyclina peruviana-r. douvillei group, that are also larger foraminifera.



4. Verrucatosporites usmensis zone late middle to late Eocene

Venezuela

lower part of zone: late middle Eocene

Helicolepidina spiralis Tobler. A larger foraminifera from Rio San Pedro fauna, Zulia, Venezuela. According to Van Raadshooven (1951), it occurs in middle Eocene beds in Maracaibo area. Proposed age is based on co-occurrence with Pseudophragmina (Proporocyclina) cf. perpusilla (Vaughan), Ferayina coralliformis Frizzell, and Lepidocyclina aff. Lepidocyclina peruviana-r. douvillei group, that are also larger foraminifera. Van Raadshooven (1951) also states that many species of larger foraminifera from Venezuela are new and difficult to correlated outside the Western Venezuelan basins.



Venezuela

upper part of zone: late Eocene







40

Lepidocyclina pustulosa H. Douville, 1917: base P12-top P17 (Robinson and Wright, 1993)

Pseudophragmina mirandana Hodson: a larger foraminifera from Rio San Pedro fauna, Zulia, Venezuela

Nummulites striatoreticulatus Rutten 1928: middle P12/P14 - top P17 (Robinson and Wright, 1993).

Helicostegina soldadensis Grimsdale: a larger foraminifera from Venezuela



Colombia

upper part of the zone: late Eocene Buliminajacksonensis Cushman 1925: late Eocene, in Globigerinatheka semiinvoluta and Turborotalia cerroazulenzis zones (Bolli et al., 1994), base P15- top P17.



Nigeria

lower and upper part of zone: late middle Eocene-late Eocene Chiloguembelina martini Truncorotaloides rohri Bronnimann and Bermudez: middle P9-top P14 (T&L85).



5. Cicatricosisporites dorogensis zone Oligocene

Caribbean

Globigerina ampliaperturata middle P16 to P20, late late Eocene to early middle Oligocene (T&L85; Bolli and Saunders, 1985) G. ciperoensis ciperoensis P20 to middle P22, middle to early late Oligocene (Bolli and Saunders, 1985)

Globorotalia opima opima P21, late middle Oligocene (Bolli and Saunders, 1985) G. kugleri Bolli 1957, P22-N4, late Oligocene to early Miocene (Bolli and Saunders, 1985)







41


Nigeria

G. ciperoensis ciperoensis P20 to middle P22, middle to early late Oligocene (Bolli and Saunders, 1985)

G. ciperoensis angulisuturalis P21 to middle P22, late middle Oligocene to early late Oligocene (Bolli and Saunders, 1985)

G. kugleri Bolli 1957, P22-N4, late Oligocene to early Miocene (Bolli and Saunders, 1985)

In general, the age assignments of the Germeraad zones seems to be confirmed by the foraminifera (Fig. 5-2). However, the level of resolution is low compared to foraminiferal zones. The early and middle Eocene, and the Paleocene-Eocene boundary are very poorly resolved. Also, the lower boundary of the Verrucatosporites usmensis zone could be older than currently assumed (early? middle Eocene). The stratigraphic position of the foraminifera in relation with sporomorph ranges, however, was not presented in their paper with the exception of three sections in Nigeria. These three sections contain only planktonic zones P4 to P14 (Upper Paleocene to middle Eocene). It is difficult, then, to evaluate the calibration of the Germeraad zones especially for the middle and late Eocene.

Regali et al. (1974) also established several palynological zones for the

Paleocene-Eocene of Brazil. The age for each zone is given by correlation with a planktonic foraminifera zonation for Brazil. Unfortunately they did not state what foraminifera taxa were used to calibrate the zonation, precluding an analysis of their data. However, it is evident a disparity in age assignments when compared with Germeraad et al. (1968) zones. For example the range of Proxapertites cursus is considered early Eocene, while it is Paleocene in Germeraad et al. (1968) scheme. When Germeraad et al. (1968) and Regali et al. (1974) zonations are compared (Fig. 5-3), it is evident a large discrepancy in the chronostratigraphic significance of many taxa. An 84% of the taxa








42


Germeraad


Regali vs Germeraad


60 50 40 My 30
EP LP EE ME LE O

Regali


Muller


Germeraad vs Muller


4050




60


EPI LP I EE


ME LEI 0
Germeraad


Regali vs Muller


Muller


45


X


....,....... ,,,....,,I
60 50 40 MY 30
EP LP EE ME LE 0 Muller


Muller vs Tibui


*1


50


55-


65


7V


o277


+245


090


240


333 314
336


o163


0


I . . I I . . . . ,
100 200 300
TIBUI


m. 400


+ 112 170 28 295 296


Figure 5-3. Comparison of Germeraad et al. (1968), Regali et al. (1974), and Muller et al. (1987) zonations. Name of taxa are in Table 5-6. Tibui section (Gonzalez, 1967) is compared against Muller's zonation suggesting a hiatus in the zonation. Circles=first appearance datums, Crosses=last appearance datums.


888 0
170o 80o
889
17242o 240

294 o

187+ 220o

163o 245+

184 +
336 100o 240o
218 2%


NJu.
My 240

00
80
40 o42

220 0 0
294 172


50
240336
296218 170
100 245+ 0
100

60

163

60 50 40 My 30


Regali


My 4050





60


889
240
240o 220o
296 888
80
219

170 218
100o 0 0 90+
294 42 245+ 172

336333


163


. . . . . . .







43


compared have discrepancies in the assumed chronostratigraphic value of first (FAD) and last appearance (LAD) datums (e.g., LAD of Cicatricosisporites dorogensis (#42), Perisyncolporites pokornyi (#172), Perfotricolpites digitatus (#170), etc.). A zonations is supposed to represent the absolute stratigraphic ranges of all taxa included. Here, evidently either both zonations are local in extent and/or they do not have the true range of most of the taxa involved.

Muller et al. (1987) established 11 palynological zones. Their work is mainly based on the Germeraad et al. (1968) zonation. Several modifications were done. The lower part of V. usmensis zone is considered middle Eocene, and the middle Eocene is subdivided into 6 zones. However, they did not provide independent data supporting the new age assignments as well as range charts of any of the sections analyzed. Colmenares and Terin (1993) and Sarmiento (1992) have challenged the regional application of these zones for western Venezuela, and central Colombia. Some of their zones could be ecological assemblages (Colmenares and Terin, 1993). A great discrepancy in biostratigraphic ranges and their chronostratigraphic significance is evident when comparing Muller with Germeraad and Regali's zonations (Fig. 5-3). Muller et al. (1987) and Germeraad et al. (1968) have a discrepancy of 47% in the range of the taxa compared (8 out of 17 taxa); while Muller vs. Regali have a discrepancy of 66% (12 out 18 taxa). Furthermore, the comparison of the sporomorph record of a section in the Catatumbo area (Gonzalez, 1967) with the Muller et al. (1974) zonation (Fig. 5-3) suggests a major hiatus in the zonation, casting serious doubts on the temporal and spatial significance of Muller zonation for the Eocene.

In summary, there is weak support and low resolution for age assignments of the palynological zones that have been proposed for the Paleocene-Eocene of northern South America. Subdivisions of the Eocene, and the exact paleontological and stratigraphical position of the Paleocene-Eocene boundary are still elusive.






44


Results

Using the graphic correlation technique (Shaw, 1964; Edwards, 1984;

Edwards, 1989), a Composite Section (CS) was developed based on the stratigraphic distribution of pollen, spores, and dinoflagellate cysts of the three sections studied (see range charts in Tables 5-3 to 5-5) and the only two additional sections available from literature with palynomorph range charts and samples referenced to a stratigraphic position in a measured section (Tibui section in Catatumbo area after Germeraad et al., 1968, and well TI in Maracaibo Basin after Rull, 1997b). Eightyfour palynomorph taxa were selected to be used in the graphic correlation. This selection was based on common occurrence in all or most of the sections and a recognized chronostratigraphic potential based on experience of previous zonations (Germeraad et al., 1968, Regali et al., 1974, Muller et al., 1987). First and last appearance datums (FAD and LAD respectively) for the five sections are summarized in Table 5-6. Also, abundance peaks of selected taxa (e.g., Longapertites) were included to evaluate their potential as a chronostratigraphic correlation tools. For Tibui section, 0 meters was assumed to be at the base of section in the Figure 3 of Gonzalez (1967). Gonzalez (1967) datums for Cicatricosisporites dorogensis and Verrucatosporites usmensis group were excluded from the analysis because he did not provide photographs of the grains and serious doubts have been made on Gonzalez' correct identification of these two taxa (Germeraad et al., 1968). For TI well (Rull, 1997b), 0 meters was considered at depth 2700 increasing upwell (Rull, 1997b, Fig. 3, p.82).

Five rounds of correlation were performed on the five stratigraphic sections in order to produce a Composite Section (a detailed explanation of graphic correlation procedure is given in Chapter 3). The two first rounds of correlation are shown in Figures 5-4, 5-5, 5-6, 5-7, 5-8, 5-9, and 5-10. The processes were repeated until ranges of each taxon stabilized. The first and last appearance datums of the taxa in






45

final Composite Section (CS) are shown in Table 5-7. Each of the sections was, then, correlated with the CS (Figs. 5-11 and 5-12).

The Composite Section (CS) was also compared with two sections of the

Germeraad et al. (1968) work that had palynological range charts but lacked an exact stratigraphic position. Samples were identified instead with labels that do not correspond to stratigraphic position of the sample. However, the paper provided the thickness of each formation where the samples were taken. In order to use this information, I assumed that samples were equidistant across each particular formation. This probably will produce an indeterminate error in the correlation but it is preferred to not using the information at all, given the small amount of published information. Datums used for these two additional sections are shown in Table 5-8, and correlations in Figure 5-13. Datum information from these two sections was not included in the CS because the uncertainty in sample stratigraphic position.

The calibration of the CS against the international time table is a difficult task given the lack of published information on planktonic foraminifera and/or magnetostratigraphy in sections where palynological work has been done. Germeraad et al. (1968) mentioned a number of foraminifera associated with their zones (see the discussion in previous studies above). However, they only presented stratigraphic positions of both foraminifera and sporomorphs for three sections (one well and two outcrop sections), all of them from Nigeria. The two Nigerian outcrop sections (Imo and Ovim Bende) do not have a vertical scale, thickness of the formations, or depth of samples. In spite of this problem, the sections were used because they are some the few sections that have both planktonic foraminifera and pollen information. Thickness for each formation was assigned from the type sections for each formation, Imo Shale=-1300m, and Ameki=-900m (Nigeria, 1956), that are located near the place were sections were measured. Samples were then uniformly spread along each formation (datums used are shown in Table 5-8). A fourth section, Itori borehole, also is from









46


56


21 1563
213


0


Q










C;
5


- XX,.


800-~ 700 600500300600



















200100-


2,97


292
0


7
+ 0137
3 5 7

0
221
36


oFAD + LAD
* Peak


El shale El sandstone


177


137 1558


100


187
0


200


300


m 400 Regadera


Figure 5-4. First round of correlation. Pinialerita (Reference Section) versus Regadera. SeeTable 5-6 for the names of the taxa used in graphic correlation. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.


32 30
0+ +0 +110
112131 320 165+
282+282 1 10
3 0221 0203 61
76 07
A 45237 134 82
257 _,25223 7 134 SI 12
0 15 o119 172 1sK 80
131 181 2181I0
0 043
336 163 29636












297


A


0


.. . . . . . . . . . . . . . . . .


0


------------------ ------------ - ..


150 5
149








47


800
c.u. 2760
149

273
2950 261o 0
0240 150 1700 314o +
14
112o 900 0
298 1 3
2960 131 0 336

600






500

00



0 4000~




300 - 28 255


245



200 - 2780 oFAD

+ LAD
a Peak

93 Oshale
100 - Esandstone


255o 235o +
235

0 . . . . . .. . , . . , . . . , . , . . . .
0 100 200 300 m400
..............................Tibui

Figure 5-5. First round of correlation. Composite Section versus Tibui. Tibui section after Gonzalez (1967). See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.








48


800185+ + 63

C.u. 1863 170

700 - 2 + -)10 +
172 42 314o 27
1810 1 19 31 600 333 63 336
20 170


S) 500 0295 0112


O 400


0

300
100 + 245 240
+93 0

200



100 93

2550

0 ,..,.......... . .. ..
0 200 400 600 m. 800 T4
900 c.u.
213 149
185+ 2- 28-1~ + +1 +112 2+3 12 +\, \,6+76 700 120 23
336 0 13I0 29
0 9 00
600 - 181 90

500 354 + 9 oFAD
57
0. -W a Peak
E 2-57
0 0
U 300 2
36 8240 Oshale
200 . sandstone

150

- 10Urb




Figure 5-6. First round of correlation. Composite Section versus T4 and Uribe sections. T4 after Rull (1997b). See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.








49


c.u.
C.U

700 600500






400 300






200100


56
+.


112 31 +131


76 +282 +186 + +221
+,13 +57 237
+ +150


+163 165+ +187


134


80
0


282






0 1, Y8o,1226
012 213 0 360

.. 131 0 09








































187
*


...I.... . ......... ........ . . . .


0


,
100


200


300


oFAD + LAD a Peak


. . . Regadera m. 4W00


Figure 5-7. Second round of correlation. Composite Section versus Regadera. See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Datums of Composite Section derived from Regadera are excluded. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.


800


0





0

0 U-


0







50


800- 149 170


c.u. 273
+ 31

700- 150+
77
0
163








0 500
149
275

0
Q.
E 4000





93 245

o FAD + LAD 278 a Peak
200- 0





100

255 235 0 0


0 . . . .... . . . .... ..... .. T ibui
0 100 200 300 m. -M

Figure 5-8. Second round of correlation. Composite Section versus Tibui. See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Datums of Composite Section derived from Tibui are excluded. First appearance datums= FAD, last appearance datums=LAD.








51


185 +
220
184+ 218 31
218 0
21900 g eg
420 31 277
333 C
2 0 0 0336 o170
296 0163


c


.U.

700


600 7 500 7'


400300


200 100 0-


) 100 200


o 112


240
0


o FAD + LAD Peak


255
0


...,..
300


400 500 600 700 m.80w T4


0 2113


18 213 149
+ 282 + +112
12+ + +76
184 150 -----D
31
0
336 219 0 18190
333 282


112
o9 149 5


0
2570
234240


188 235 187 00 0


0 36

1400150
24601
0 185


0 .... 10 0, .. ... ". 500 600..
0 100 200 300 400 500 600


73
0


700 8Wm 900 Uribe


Figure 5-9. Second round of correlation. Composite Section versus T4 and Uribe. See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Datums of Composite Section derived from T4 and Uribe are excluded.


0 .

0
U


295 o


100


0 C.)


.7

0 Q.
E
0 U~


900 C.u.
800

700O


600 500

400 300 200 10 -


800


+






93


U








52


800


c .u.

700 600 500




400 300




200 100




0


.. 1.
300


400 500


600


700 m. 800
Pifialerita


Figure 5-10. Second round of correlation. Composite Section versus Pifialerita. See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Datums of Composite Section derived from Pifialerita are excluded. First appearance datums= FAD, last appearance datums=LAD.


0
.0



0

0
U


o 100 200


++

S2V5 + 0

221 0
0V 64 00
30

0

60 0 36 49 0 0
-+







100 298 257 273
245
234 276
0 0

A186
187
234
0

o FAD 22 + LAD a Peak








53


+ 185 3 14 1o 180

+ 184 0
294 0 ()80 181 _ 0218 314 277 172 10 0 31
2 6 163
333 033? 296 17(0
29 o112 o


93245100
344 240 o





93
S255 o


6W0500


400 7 300


200100 0-


. ...0 .0 60.......0,.. ... ,......
300 400 500 600


o FAD + LAD A Peak


|shale Elsandstonel



- ". T 1 700 M.800


700






500


4 300


200 100


V


800


0 CL
.2



0 U..


C.u.

700 600


500



400 300 200 104


P. ......., .... . . . , ,. . , . .,,,,
0 100 200 300 m. 400
Regadera


149+ + 0
273+ 314
+150 23 5
314 255 261
163
296 1 0336
295 17 333
112
1490
275



257 298
- 245 93 273

276234
240
2780




2550 2350 , . . .


0 100 200 300 m-400
'.. i Tibui


Figure 5-11. Line of correlation for well T1, Regadera, and Tibui sections versus Composite Section. See Table 5-6 for names of the taxa used in graphic correlation. First appearance datums= FAD, last appearance datums=LAD.


-I


800 c.u.
700


0


0.
2
0 U-


1...............
0100 200


800 C.u.


0~
C .
E
0


+56 28-T + 8IV
186 76 +221
* *+237 13-4 80
213 7 + 3 2
23 150t 30 261
218 0 207 35 32 0 8D>72
+ , '7 0 0 7 1633 0 219 390
2 96 ~181 0297 134
Q213 165 o 112
A 0297
150
149



0 257


o 221





187 0








54


282 1149 + + 187 11,2 185+ ++ +1g 7

150 1 7
031
354 12 29
+ -0 0
0 1810
S282 90
333 64
S336 0 112
213 04 8 57


800C.u.
700


600

0
U. 500 7









200


100


0 36


o FAD + LAD * Peak


Oshale Sandstone


o 234 o 240


0 o 187
188 235 0


73
0


FAD uri


1


0 100 200 300 400 500 600 700 800 900 1000 1100
Uribe 800-


A6 2d7k 3A0 4di


5 .o ... 7d() flLX Pifialerita


..................................~ ~


Figure 5-12. Line of correlation for Uribe and Pifialerita sections versus Composite Section. See Table 5-6 for names of the taxa used in graphic correlation. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.


0 257


f)


0
0 150
246
o 185


c.u.


0 C.)


0
U


600






.400-7 300


200 100


0


+ 0

+ 2)0
00 0
0
0
+ 0 8





+ + 00 0

+ 0 0 0


....... .... ...


6








55


800c.u.
700


600


500


400
0

0
U 300


200 100


0


800 c.u.
700 600

0
500


-V 400
0
E
0
G 300


200 100


0


163

184+ 218o 294
29 3360 1 0 42
296





245 28
100

2400




100

28o


..............-e.-e......."."..."'"1
0 100 200 300 00 500 600 700 m80



220 184+ 9
80
21 o 172 42 3360 163
296 170






-100

2400



100

187


0


100 200


300 400 500


600 700 m-8(


Figure 5-13. Line of correlation for Rubio Road and Paz de Rio sections versus Composite Section. Sections after Germeraad et al. (1968). See Table 5-6 for names of the taxa used in graphic correlation. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account


Rubio road


Paz de Rio


..........





-










Table 5-3. Palynomorph distribution in samples from the Pifialerita section


Taxa Sample code 1 4 5 6
Aglaeoreidia? "foveolatus" Araucariaciates "rugulatus" Araucariaciates "scabratus" Baculamonocolpites "bimodalis"
Baculamonocolpites "curubensis" Baculatisporites "irregularis" Baculatisporites "soleus" Bacutriporites "echinatus" Bombacacidites "caldensis" Bombacacidites "etayoi" Bombacacidites "fossureticulatus" Bombacacidites "gentryi" Bombacacidites "nissoides" Bombacacidites "protociriloensis" Bombacacidites "protofoveoreticulatus' I Bombacacidites "sabanensis" Bombacacidites "simplireticulensis" Bombacacidites annae 34 70
Bombacacidites brevis Bombacaciditesfoveoreticulatus Bombacacidites nacimientoensis Bombacacidites soleaformis Bombacacidites sp. C Brevitricolpites "macroexinatus" Brevitricolpites "microechinatus" Brevitricolpites "scabratus" Chomotriletes minor Cicatricosisporites "infrafoveolatus" I Cicatricosisporites dorogensis C. dorogensis subsp. minor forv. rugulatearis Cicatricososporites "decussatus" Cicatricososporites eocenicus Clavamonocolpites "macroclavatus" Clavatisporites mutisi Clavatricolpites "densoclavatus" Colombipollis tropicalis


7 8 9 10 11 12 15 16 17 18 19 21 25 27 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49


6


3 1


I I


3 8 3 2 1 1


2 1 2 2 1


4 18 5 9 3


1 6


29 3 60 6 3


7


12 1 9 7 7 4 19


1 1 3 1 1 1


2


2 1


10
2


4 7 6 5 15 4 22 26


64


15 89 14


3 3 2 1 1
4 1 3


3


2 15 9 8 13 2 6 4


4 2 1 4


I


I


I


I


I


1


I


I


I


I


1


I


I


I


I


1


I


I











Table 5-3--continued.


Taxa Sample code 1 4 5 6 7 8
Cricotriporites "macropori" Cricotriporites guianensis Cricotriporites minutipori Cricrotriporites "porielongatus" Crototricolpites "protoannemariae" 1 6 Ctenolophonidites "cruciatus" Curvimonocolpites inornatus 5 2 2 1 4
Cyclusphaera "scabratus" Echimonocolpites "tenuiechinatus" I
Echinatisporis "brevispinosus" Echinatisporis "microechinatus"
Echinatisporis "obscurus" I
Echinatisporis "portae" Echinatisporis? "cingulatus" Echipericolpites "brevicolpatus" Echiperiporites "scabratus" Echiperiporites estelae Echitetracolpites "echinatus" Echitetracolpites "tenuiexinatus" Echitricolpites "linearis" Echitriporites "annulatus" Echitriporites "spissuexinatus" I
Echitriporites "variabilis" Echitriporites trianguliformis var. "orbicularis" Ephedripites vanegensis I
Fossutricolporites "microreticulatus" Foveodiporites guianensis 2
Foveotricolpites "costatus" Foveotricolpites perforatus Foveotricolporites "brevicolpatus" Foveotricolporites "fossulatus" Foveotricolporites "marginatus" Foveotricolporites "poricostatus" Foveotricolporites "rugulatus" Foveotriletes "fossulatus" Foveotriporites "poricostatus" Foveotriporites hammenii


9 10 11 12 15 16 17 18 19 21 25 27 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
1 1 4


1 1 2 1


3 1 2 4 31

2


4 1


6 1


I I


3


1 6 1 6 2 2 15


4 5


I I I


3


I I


1 4


I I


2


2
1


I I 6 1
5 4


2


3 5 10
1 1 3 1 2 5


2 2


1
6


1 4 2



1 1 2


3 1 1 3 1 1 1 4 2 4 8 3 7 2 12 4


3
4 2 3


16
1


4 2


2


1 3


2


12


2


2 2 3 2


1 2 3 1I

2
1 3


I


I


I


I


I


1
1


I


I










Table 5-3--continued.


Taxa Samplc code 1 4 5 6 7 8 9 10 1 12 15
Gemmamonocolpites "mammiformis" I Gemmamonocolpites "megagemmatus" Gemniamonocolpites "perfectus" Gemmanonocolpites gemmatus 5 1
Ischyosporites "problematicus" 4
Jandufouria "minor" Jussitriporites "psilatus" 3 1 1 1 1 2 1 2
Jussitriporites undulatus Kirchheimerisporites "tenuiradiatus" Ladakhipollenites rubini Ladakhipollenites simplex Laevigatasporites "laevigatus" 1 2 5
Loevigatosporites "barcoi" Laevigatosporites "tenuiexinatus" Laevigatosporites tibui 1 2 1 2 25
Longapertites "ornatus" Longapertites microfoveolatus 4 2
Longapertites proxapertitoides var reticuloides Longapertites proxapertitoides var. proxapertitoides I Luminidites "colombianensis" M.franciscoi var.franciscoi 1 11 8 6 3 43 17 35 2 15 7 Mauritiiditesfranciscoi var. minutus I 1 1 3 2 1
Mauritiidites franciscoi var. pachyexinatus Microfoveolatosporis skottsbergii Momipites "pachyexinatus" Momipites africanus 2 2
Monoporopollenites annulatus Nothofagidites "huertasi" Osmundacidires "dispergatus" 2
Osmundacidites "minor" Perfotricolpites digitatus Periretisyncolpites "inciertus" 3 2
Perisyncolporites pokornyi Polypodiaceoisporites? "fossulatus" 1 2
Polypodiisporites "densus" Polypodiisporites "echinatus" Polvpodiisporites "pachycxinatus"


16 17 18 19 21 25 27 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49


I I


1 8


2 1


9 1


6 9


13 3


2
1


1 4 8 2 1 6


2
3 1 1 2


1 1


8 22 1 4 4 48 126 169 186 39 65 39 72 52 27 41 57
1 2 1


246 1
1 1 1 148 1


14 17 4 2


1 5 2 2 3 1


1 1
1 1 9 1 3 1 32 10 22 22 6 5 15 4 5 6 7 7
5 I 5 7 13 10 1 2 1 3 2 1
2 3 3 1 1


4 1


6 1


1 1 1


2 2


1 2 3 3 1 3 3
5 13


4 2


6


4 3 1 1 4 3 10 13 9 14 11 49 7
1 1 2 2 6 3


3


I


I


I


I


I


I


1
1


I


1


I


I










Table 5-3--continued.


Taxa Sample code 1 4 5 6 7 8 9 10
Polypodiisporites "protousmensis" I I
Polypodiisporites specious Propylipollis "pseudocostatus" Proxapertites cursus 1 2 1 1 97 1 253
Proxapertites humbertoides 13 1
Proxapertites magnus 2 16 6 12 16 5
Proxapertites operculatus I I 1 61 4 61
Proxapertites psilatus I
Psilabrevitricolpites "costatus" I
Psilabrevitricolpo rites "costatus" Psilabrevitricolporites "operculatus" Psilabrevitricolporites simplifornis 1 2 Psilamonocolpites grandis 57 4 3 2 6 1
Psilamonocolpites medius 8 4 15 5 4 2 8
Psilaperiporites "enigmaticus" I Psilaperiporites "pachyexinatus" Psilaperiporites "pauciporatus" Psilastephanocolpites "marginatus" Psilastephanocolpites "punctum" Psilastephanocolporites "brevicolpatus" Psilastephanocolporites "pachyexinatus" Psilastephanocolporites "psilatus" Psilastephanocolporites fissilis Psilastephanoporites "distinctus" Psilastephanoporites "scabratus" Psilasyncolporites "psilatus" Psilatricolporites "crassicolumellatus" Psilatricolporites "orbicularis" Psilatricolporites "poricostatus" Psilatricolporites "singularis" Psilatricolporites "spongiosus" 4
Psilatricolporites crassus Psilatricolporites maculosus Psilatricolporites operculatus Psilatricolporites transversalis Psilatricolporites triangularis Racemonocolpites "costagemmatus"


11 12 15 16 17 18 19 21 25 27 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
1 1 1 1


8
I I
6 6 1 21
1


6
2 18
4


4 6
10
6 57 4 26


2

4 2 1 2 25 4 I


9


3 1 2


1 2
6


321


2 33 32 35 13 22 31 21 86 12 12 15 14

1 1


1


2 3 1


2


4 3 5 1 6 1


6


2


2
1 4 1 2


3


5 4 8 6 3 4 3


3 10 9 1 6 2 1 1 2


2


2


I I


2 3


1
2
1


1 4
2
I I


2
1


4


14 1


31 3 11 36 34 2 13 7 63 4 1 3 I 6 17
2 2 3 4 2 5 3 3 5 4


2


2 4 1 1 4 1


I


I


I


I


I


I


1


I


I


I


I


I


I


1


I


I


I










Table 5-3--continued.


Taxa Sample code 1 4
Racemonocolpites facilis Racemonocolpites racematus Retibrevitricolpites "costatus" Retibrevitricolpites "santanderensis" Retibrevitricolpites retibolus Retibrevitricolpites triangulatus
Retibrevitricolporites "grandis" Retibrevitricolporites "speciosus" Retidiporites "poricostatus" Retidiporites elongatus Retidiporites magdalenensis 33
Retimonocolpites "ovatum" Retitnonocolpites regio 3
Retipollenites "baculatus" Retipollenites "magnus" Retistephanocolpites "fossulatus" Retistephanocolpites "gradatum" Relistephanocolpites "inciertus" Retistephanocolpites angeli Retistephanocolporites "fossulatus" Retistephanocolporites festivus Retistephanoporites "crassiexinatus" Retistephanoporites "minutipori" Retistephanoporites angelicus Retisyncolporites "complicatus" Retisyncolporites "delicatus" Retitricolpites "baculensis" Retitricolpites "costatus" Retitricolpites "marginocostatus" Retitricolpites "peculiaris" Retitricolpites "protoclarensis" 2 Retitricolpites absolutus Retitricolpites antonii Retitricolpites clarensis Retitricolpites florentinus Retitricolpites magnus Retitricolpites saturum


5 6 7 8 9 10 11 12 15 16 17 18 19 21 25 27 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
1 1 1

2

6
1 1 3


9


9
1


2 38 2 5
20 9 3 180
18 16 5 5 6 10 3 3


2


2
33 25 14
1


1 2 1


2 5


1 2
10 2 3


3 1 4 30 12 38


4 1 4 9 8 3 6 2 7 7 5 5 2 812



1 1 1 6 6 1 8 2 9
1
1


1 2 2 1 2


3


1 2 1 1 4 3 2 3
1
1 1 2 3 11 3 16 5
1 19 12 7 12 4
1


1 1


2 2 1


1 3 3


4


2 5


1 2 7
2 1 3 2 2


3


I I


I I


2
1 1


6 28 15 4 9 4 4 1


I


1
1


I


I


I


I


I


I


I


I


I


1


I


I











Table 5-3--continued.


Taxa Sample code I
Retitricolporites "arctus" Retitricolporites "delicatus" Retitricolporites "distinctus" Retitricolporites "insolitus" Retitricolporites "longicolpis" Retitricolporites "marginatus" Retitricolporites "minutus" Retitricolporites "pachynexinatus" Retitricolporites "poricostatus" Retitricolporites "tropicalis" Retitricolporites "vestibulatus" Retitricolporites cienagensis Retitricolporites guianensis Retitricolporites hispidus Retitricolporites irregularis Retitricolporites mariposus Retifricolporites medius Retitricolporites squarrosus Retitriletes "enigmaticus" Retitriporites "amplireticulatus" Retitriporites "annulatus" Retitriporites "pachyexinatus" Retitriporites "peculiaris" Retitriporites "perforatus" Retitriporites "poricostatus" Rugotricolporitesfelix Scabrastephanocolpites "casanaris" Scabratricolporites "tomassoi" Spinizonocolpites "breviechinatus" Spinizonocolpites "grandis" Spinizonocolpites "pachyexinatus" Spirosyncolpites spiralis Striatricolpites "orinocus" Striatricolpites catatumbus Striatricolpites minor Striatricolporites "digitatus"


4 5 6 7 8 9 10 11 12 15 16


17 18 19 21 25 27 32 33 34 35 36 37 38 39 40 41 42 43 44 45
3
1 1 1


2 1


46 47 48 49


1 2


2


I 1


2


10 2


3


I I


4 1


1 2


3 19 17 9 4 17
5 3 1
1 3 1


3


12
1
1


2 1 1 2
1


10
1
2


1
2


1 2
2
1 5 8 1
6
1 2 3


ON


4


2 2


2


1 2 1


1 1 2


5


4


I 1 1

20 3 5 7 9 2 6 6 4


15 3 4 2 1 3 1 1 1


2 2


9 5 8 5 25


1 1 6 3 3 2 3 9


I


I


I


I


I


I


I


1


I


I


I


I


I


I


I


I


I


I


I


I











Table 5-3--continued.


Taxa Sample code I
Striatricolporites "reticulatus" Syncolporites "verrucatus" Syncolporites lisamae Tuberositrileles "verrucatus" Tuberositriletes? "inciertus" Ulnoideipites krempii Verrustephanocolpites "rugulatus" Verrustephanoporites "gemmatus" Verrutricolpites "irregularis" Verrutricolporites "reticulatus" Zlivisporis blanensis Zonocostites "minor"
"Psilatriletes" sp. A "Psilatriletes" sp. B "Psilatriletes" sp. C Acritarcha sp. A Acritarcha sp. B Acritarcha sp. C Bacuinaperturites sp. A Bombacacidites sp. A Bombacacidites sp. B Cicatricosisporites sp. A Cingulatisporites sp. A Echidiporites sp. A I
Echimonocolpites sp. A Echimonocolpites sp. C Echinosporis sp. A Echitricolpites sp. A Echitriporites sp. B Ephedripites sp. A Fossulatisporites sp. A Fossulatisporites sp. B Fossustephanocolpites sp. A Foveotricolpites sp. A Foveotriletes sp. A Foveotriletes sp. B Gemmainaperturites? sp. A


4 5 6 7 8 9 10 11 12 15 16 17 18


19 21 25 27 32
1 1 l


33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
1 1


2 3 2 2 3


2


I I


11

2 12 10 12 3 7 29 10 22 24 2 5
3 2 16 5 59 4 5 37 5 29


I I I


1

36 16 2 3 33 22 2


13 15


17
8
17


2 2 3


1 2 1
1


31
3
21


46
3
9


35 25
2 2 10 3


43
1
3


7 36 1


7 1 65 17 3 5 3 1


2 26
4
1


2
24
2


27
3
2


38
7


4


24
1
1


3


I


I


I


I


I


I


I


1
l


I


I


1


I


I


I


I


I


I


I


I


I


I


I


I


I










Table 5-3--continued.

Taxa Sample code
Incertae sedis sp. A Ladakhipollenites sp. A Ladakhipollenites sp. B Laevigatasporites sp. A Laevigatasporites sp. B Longapertites? sp. A Mauritiidites sp. A Microfoveolatosporis sp. A Nematosphaeropsis sp. A Polypodiisporites sp. A Psilasyncolporites sp. A Psilatriporites sp. A Psilatriporites sp. B Psilodiporites sp. A Retibrevitricolpites sp. A Retimonocolpites sp. A Retimonocolpites sp. B Retistephanoporites sp. A Retisyncolporites sp. A
Retitricolpites sp. A Retitricolpites sp. B Retitricolporites sp. A Retitricolporites sp. B Retitricolporites sp. C Retitricolporites sp. D Retitricolporites sp. E Retitricolporites sp. F Retitriporites sp. A Rugotricolporites sp. A Rugotricolporifes sp. B Rugulatisporites sp. A Scabrastephanoporites sp. A Scabratisporites sp. A Scabratricolpites sp. A Scabratriporites sp. A Striatricolporites sp. A Striatriporites sp. A


1 4 5 6 7 8 9 10 11 12 15 16 17 18 19 21 25 27 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49


2
14 1


17


2


4 2


3


1 1


1



2


3


2


6


I


I


I


I


I


I


I


I


I


I


I


I


I


I


1


I


1


I


I


I


I


I










Table 5-3--continued.

Taxa Sample code
Syncolpites sp. A Syncolporites sp. B Tuberositriletes sp. B Verrustephanoporites sp. A Verrutricolporites sp. A Verrutricolporites sp. B Verrutricolporites sp. C Achomosphaera sp. A Cordosphaeridium sp. A Coronifera sp. A Dinocyst indet. Glaphyrocysta sp. A Homotryblium floripes Hystrichosphaeridium sp. A Incertae dinocyst C Lingulodinium cf. sicula
Microforaminiferal lining Pediastrum
Polysphaeridium sp. A Pterospermella sp. Spiniferites sp. A Systematophora? sp. A Trachelomona sp. Aequitriradites verrucosus (RW) Bombacacidites annae (RW) Buttinia andreevi (RW) Circulodinium distinclum (RW?) Foveotriletes margaritae (RW?) Oligosphaeridium sp. (RW) Bacutricolpites sp. Bombacacidites sp. Brevitricolporites sp. Cingulatisporites sp. Clavastephanocolpites sp. Clavatricolpites sp. Clavatriporites sp. Echipollenites sp.


1 4 5 6 7 8 9 10 11 12 15 16 17 18 19 21 25 27 32 33 34 35 36 37 38 39 40
3


41 42 43 44 45 46 47 48 49


2


6
30

22


3 4 1
1 21 1 1


2


S 1 2 1
1 1 4


2 2
2
3 3 1 10 44 3


I I 1


5 1

52 1 1 2 2 4 2 5


7


2


1 4 3 1 2 1 3 2


2


2


1 1 3


I


I


I


I


I


I


I


1


I


I


I


I


I


I


I


I


I


I


I


I


I


I










Table 5-3--continued.

Taxa Sample code
Echistephanoporites sp. Echitriporites sp. Foveomonocolpites sp. Foveostephanocolpites sp. Foveostephanocolporites sp. Foveotricolpites sp. Foveotricolporites sp. Foveotriletes sp. Foveotriporites sp. Incertae sedis sp. Jussitriporites sp. Ladakhipollenites sp. Loevigatasporites sp. Laevigatosporites sp. Leiosphaeridia sp.
Megaspore Pollen indet. Psilabrevitricolpites sp. Psilamonocolpites sp. Psilastephanoporites sp. Psilatricolporites sp. Psilatriporites sp. Retibrevitricolporites sp. Retimonocolpites sp. Retimonoletes sp. Retipollenites sp. Retistephanoporites sp. Retisyncolporites sp. Retitricolpites sp. Retitricolporites sp. Retitriletes sp. Retitriporites sp. Rugopollenites sp. Rugutriletes sp. Scabrastephanoporites sp. Scabratricolpites sp. Scabratricolporites sp.


1 4 5 6 7 8 9 10 11 12 15 16 17 18 19 21 25 27 32 33 34 35 36 37 38 39 40


1 1 2


2


2


2


I I


5


5


1 6 5 58


2


2 1 1 2


2 3 1


2 2


2


2


2


3 1 1 1 2 1
1


I1 1 22 11 1 2 1


10


I I


1 3 1


2
2


4
3


2 2 1


7
9


1 3
5


2
1


4
1


3 11


6
3


7 5 1
3 1 3 3 4 5 7


1 2 1


5


41 42 43 44 45 46 47 48 49


5 1 1 2


6
6


3
3


2
3


5
3


1 1


I


1


1


1


1


I


1


1


1


1


I


1


I
1

I


1

I


I


I


I


I


1









Table 5-3--continued.

Taxa Sample code
Scabratriporiles sp. Spinizonocolpites sp. Siriatricolporites sp. Verrucatosporites sp. Verrustephanoporites sp. Verrutrileies sp. Zonofriletes sp.


1 4 5 6 7 8 9 10 11 12 15 16 17 18 19 21 25 27 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49


2
1 10


I 2
2


4


1
4


Key to sample code (meters from base of Arcillas de El Limbo Formation). Samples that are not in the range chart were sterile for palynomorphs


I = NA -2 (-5.4 m.) 2 = NA -l (-3.6 m.)
3 = N 0+60 (-1.2 m.)
4 = N 4 (5.4 m.)
5 = N 18 (30.6 m.)
6 = N 21 +l00 (37 m.)
7 = N 27 (46.8 m.) 8 = N 45 (79.2 m.) 9 = NA 46 (81 m.) 10 = NA 59+90 (105.3 m.) I 1 = N 74 (131.4 m.) 12 = N 87 (154.8 m.) 13 = N 90 (160.2 m.) 14 = N 100 (178.2 m.) 15 = N 110 (196.2 m.) 16 = N 114 (203.4 m.) 17 = N 120 (214.2 m.)


18 = N 131 (234 m.) 19 = N 149 (266.4 m.) 20 = N 157 (280.8 m.) 21 = N 174 (311.4 m.) 22 = N 181 (324 m.) 23 = N 201 (360 m.) 24 = N 216 (387 m.) 25 = N 241 (432 m.) 26 = N 254 (455.4 m.) 27 = N 265 (475.2 m.) 28 = N 265+150 (476.7 m.) 29 = N 283 (507.6 m.) 30 = N 325 (583.2 m.) 31 = N 349 (626.4 m.) 32 = N 354+120 (636.6 m.) 33 = PIN 0 (639 m.) 34 = PIN 12 (660.6 m.)


35 = PIN 19+60 (673.8 m.) 36 = PIN 24+90 (682.2 m.) 37 = PIN 28+0 (689.4 m.) 38 = PIN 32+0 (696.6 m.) 39 = PIN 35+90 (702.9 m.) 40 = PIN 39+166 (710.8 m.) 41 = PIN 42+100 (715.6 m.) 42 = PIN 47+100 (724.9 m.) 43 = PIN 52+110 (733.7 m.) 44 = PIN 55+30 (738.3 m.) 45 = PIN 63+20 (752.6 m.) 46 = PIN 66+80 (758.6 m.) 47 = PIN 71+10 (766.8 m.) 48 = PIN 75+160 (775.6 m.) 49 = PIN 81+0 (784.8 m.)


I


I


I


I


I


I


I








67

Table 5-4. Palynomorph distribution in samples from the Regadera section


Taxa sample code 1 2 3
Araucariaciates "rugulatus" Baculamonocolpites "curubensis" Bonbacacidites "dilcheroi" Bombacacidites "psilatus" Bombacaciditesfoveoreticulatus Bombacacidites soleaformis Brevitricolpites "microechinatus" Cicarricosisporites dorogensis C. dorogensis subsp. minor forv. rugulatearis Clavatricolpites "densoclavatus" Cricotriporites "macropori" Cricorriporites guianensis Cyclusphaera "scabratus" Echinatisporis "brevispinosus" Echinatisporis? "cingulatus" Echiperiporites estelae Echitetracolpites "echinatus" Echitetracolpites "tenuiexinatus" Echitriporites "retiechinatus" Echitriporites triangulifonnis var. "orbicularis" Foveotricolporites "rugulatus" Foveorriporites hammenii Jussitriporites undulatus Ladakhipollenites "gemmatus" Ladakhipollenites simplex Laevigatasporites "laevigatus" Laevigatosporites tibui L proxapertitoides var. reticuloides L proxapertitoides var. proxapertitoides 1j Margocolporites vanwijhei Mauiritiiditesfranciscoi var.franciscoi Mauritiidites franciscoi var. minutes Mauritiiditesfranciscoi var. pachyexinatus Microfoveolatosporis skottsbergii Monoporopollenites annulatus Nothofagidites "huertasi" Nothofagidites "lolongatus" Perisyncolporites pokornyi Polypodiisporites "breviverrucatus" Polypodiisporites "echinatus" Polypodiisporites specious Proxapertites magnus Proxaperites operculatus Psilamonocolpites medius Psilastephanocolporites "psilatus"


4 5 6 7 8


9 10 11 12 13 14 15 16 17


2


2 33 90

31


2 2


7
1
2



3


3
2


2
1


1 2


3
7


2



2
1


3
4



1


13
3


2
1


4
2


7 131


3 25 45
7
4


19 25


I I


2
1


3
2


5
2


2 10 14


2 2 1


3
6


7


4 7 7 16


4


3 1
3 1


1 1


I


I


I


I


I


I


1


1
1


I


I


1


1


I








68


Table 5-4--continued.


Taxa sample code
Psilastephanoporites "distinctus" Psilasvncolporites "fastigiatus" Psilatricolporites "orbicularis" Psilatricolporites crassus Psilatricolporites maculosus Psilatricolporites transversalis Retibrevitricolpites "santanderensis' Retibrevitricolporites "grandis" Retimonocolpites "ovatum" Retistephanocolpites "fossulatus" Retistephanocolporites festivus Retistephanoporites angelicus Retisyncolporites angularis Retitricolpites "perforatus" Retitricolporites "delicatus" Retitricolporites "vestibulatus" Retitricolporites irregularis Retitricolporites mariposus Scabratriporites "bellus" Spirosyncolpites spiralis Striatricolpites "tenuistriatus" Striatricolpites catatumbus Syncolporites marginatus Ulnoideipites krempii Verrutricolporites "reticulatus" Wilsonipites margocolpatus
"Psilatriletes" sp. A "Psilatriletes" sp. B "Psilatriletes" sp. C Camarozonosporites sp. A Cingulatisporites sp. B Foveotriletes sp. B Incertae sedis sp. B Laevigatosporites sp. A Mauritiidires sp. A Psilastephanoporites sp. A Scabratisporites sp. A Tuberositriletes sp. A Algae
Dinocyst indet. Incertae dinocyst A Pediastrum
Polysphaeridium sp. A Circulodinium distinctuin (RW?) Oligosphaeridium sp. (RW) Proxapertites magnus (RW)


1 2 3 4 5 6 7


8


9 10 11 12 13 14 15


2


2 85 5 12


I 1


10
7


1
2


2
2


3

3


7 1


1 6


6 15 1 1


2


1
2



1 2



45
17
49


3

5
1


3 7


3


2
2


2


2
2
3


3 10
2


2 8


1 4


16 17


13 53
5
10


I


I


I


I


I


I


I


I


I


I


I


I


I


I


I


I


I


I


I


I


I







69


Table 5-4--continued.

Taxa sample code
Senegalinium sp. A (RW?) Spiniferites sp. (RW?) Bombacacidites sp. Cingulatisporites sp. Clavatricolpites sp. Clavatricolporites sp. Colombipollis sp. Echistephanoporites sp. Echitriporites sp. Ladakhipollenites sp. Laevigatosporiles sp.
Pollen indet. Psilatriporites sp. Retistephanoporites sp. Retitricolpites sp. Retitricolporites sp. Rugorriporites sp. Scabrastephanoporites sp. Spinizonocolpites sp. Striatricolpites sp. Verrutriletes sp.


1 2 3 4
6

2


5 6 78


17
6


9 10 11 12 13 14 15 16 17


Key to sample code (meters from base of Mirador Formation)
1 = RE 39 (-12m.) 2 = RE 46 (-l.5m.)
3 = RE 49+130 (4.3m.)
4 = RE 67+120 (31.2m.)
5 = RE 83 (54m.)
6 = RE 98 (76.5m.) 7 = RE 113 (99m.)
8 = RE 132 (127.5m.)
9 = RE 143+120 (145.2m.) 10 = RE 153 (159m.) 11 = RE 170+40 (184.9m.) 12= RE 186 (208.5m.) 13 = RE 190+10 (214.6m.) 14 = RE 220 (259.5m.) 15 = RE 222+100 (263.5m.) 16 = RE 241+40 (291.4m.) 17 = RE 251+30 (306.3m.)


3


4


2 1 2
7


11 1
3


2


5 6 7 8


I


I


I


I


I


I


I


I


I


I


I








70


Table 5-5. Palynomorph distribution in samples from the Uribe section


Taxa sample code 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Anacolosidites ariani 1 1 2
Baculamonocolnites "angustus" I


Baculamonocolpites "curubensis" Baculatisporites "soleus" Bacumorphomonocolpites tausae Bombacacidites "psilatus" Bombacacidites "simplireticulensis" Bombacacidites brevis Bombacacidites nacimientoensis Brevitricolpites "microechinatus" Camarozonosporites "inciertus" Chomotriletes minor Cricotriporites guianensis Crototricolpites cf. annemariae Cyclusphaera "scabratus" Echinatisporis "brevispinosus" Echinatisporis "obscurus" Echinatisporis? "cingulatus" Echitriporites "variabilis" Echitriporites trianguliformis var. "orbicularis" Foveotriporites hammenii Gemmamonocolpites "ambigemmatus" Laevigatosporites tibui Longapertites proxapertitoides var. reticuloides Longapertites proxapertitoides var. proxapertitoides Mauritiiditesfranciscoi var.franciscoi Mauritiiditesfranciscoi var. minutus Mauritiidites franciscoi var. pachvexinatus Polypodiaceoisporites? "fossulatus" Polypodiisporites "brevis" Polypodiisporites "breviverrucatus" Poivpodiisporires "densus" Polypodiisporites "echinatus" Polvpodiisporites specious Proxapertites cursus Proxapertites humbertoides Proxapertites operculartus Proxapertites psilatus Proxapertites verrucatus Psilamonocolpites medius Psilastephanoporites "annulatus" Psilatricolporites "orbicularis" Psilatricolporites maculosus Psilatriporites "tenuiexinatus"


15 I


2


4


2 18 1 2


2 1 8 5


3


2 1 3 4


2


I I


I I


2


6


2 1


1 2
5


14


7



2


2
2 51



7



3


2


13 14 1I 16


I II1


S1I


2


2


5



5


2


I I I


1 3


3


2


I


I


I


I


I


1


1


I


I


I








71


Table 5-5--continued.


Taxa sample code 1 2 3 4 5 6 7 8 9 10
Pteridacidites "cucutensis" Racemonocolpites "costagemmatus" I
Racemonocolpitesfacilis Racemonocolpites racematus Retibrevirricolpites triangulatus Retibrevirricolporites "grandis" I
Retibrevitricolporites "speciosus" Retimonocolpites "ovatum" 1 9
Retistephanocolporitesfestivus Retistephanoporites "regaloi" Retitricolporites "delicatus" Retitricolporites "grandis" Retitriporites "poicostatus" Scabratricolporites "amplocolpatus" Spinizonocolpites "brevibaculatus" I 10
Spinizonocolpites "pachyexinatus" I
Spinizonocolpites "pluribaculatus" Spirosyncolpites spiralis I I
Striatricolpites "tenuistriatus" Striarricolpites catatumbus 3
Tuberositriletes "verrucatus" Ulmoideipites krenpii 6
Verrumonocolpites "romatus" "Psilatriletes" sp. A 5 1 I1
"Psilatriletes" sp. B 4 6 11
"Psilatriletes" sp. C Acitarcha sp. A Clavamonocolpites? sp. A Echimonocolpites sp. B Echinatisporis sp. A I
Echitriporites? sp. A I
Foveotricolporites sp. A Gemmainaperturites? sp. A Incertae sedis sp. C Laevigatasporites sp. C Laevigatasporites sp. D Longapertites sp. B Psilastephanocolporites sp. A Psilatriporites sp. C Retibrevitricolpites sp. A Retistephanoporites sp. B Retitricolporites sp. A Striatricolporites sp. A Syncolporites sp. A Tuberositriletes sp. A Algae
Algae A 3


I 12 13 14 15 16 17 18 19


1 I I


2 17 1
2


2
2

7


2


3


3


1 I 51l5


3 3
8 1


21 25


4
6


4
3
2


3


2


I I


20 21 22 23 I I


10
IO 1



24 47 20 13 9 1


I


i








i


I


I


1

1


1
i


I








72


Table 5-5--continued.


Taxa sample code I
Dinocyst indet. Incertae dinocyst B Incertae dinocyst C Pediastrum Spiniferites cf. mirabilis Alisogymnium euclaense (RW) Buttinia andreevi (RW) Dinogymnium acuminatum (RW) Dinogymnium sp. (RW) Dinogymnium undulosum (RW) Odontochitina sp. (RW) Oligosphaeridiun sp. (RW) Palaeohystrichophora infusorioides (RW) Periretisyncolpites giganteus (RW) Proxapertites magnus (RW) Senegalinium sp. A (RW?) Spinidinium sp. (RW?) Spinozonocolpites baculatus (RW) Stephanocolpites costatus (RW) Bombacacidites sp. Echipollenites sp. Echirriporites sp.
Pollen indet. Polypodiisporites sp. Psilastephanoporites sp. Psilatricolporites sp. Retimonocolpites sp. Relipollenites sp. Retisyncolporites sp. Retitricolpites sp. Refirricolporites sp. Stephanocolpate sp. Verrucatosporites sp. Verrumonoletes sp. Verrutriletes sp. Zonotriletes sp.


2 34 5 67 89


10


2



2


I 12 13 14 15 16 17


18 19 20 21 22 23


S 1 2 1


2


I I


3
5


2


I I


7


9


II I 2


2


2
1


2 4


4


4


Key to sample code (meters from base of La Paz Formation)


I =sample UR 376 (-6m.)
2 =sample UR 379 (-4.5m.)
3 =sample UR 395+120 (20.7m.) 4 =sample UR 409+70 (41.2m.)
5 =sample UR 437+5 (83m.) 6 =sample UR 445 (94.5m.) 7 =sample UR 470 (132m.) 8 =sample UR 502 (180m.) 9=sample UR 507 (187.5m.)


10 =sample UR 531+120 (224.7m.)
1 I =sample UR 542+40 (240.4m.) 12 =sample UR 545 (244.5m.) 13 =sample La Paz 361 m (361m.) 14 =sample UR 704+10 (385.1m.) 15 =sample UR 726 (418m.) 16 =sample UR 761 (470.5m.) 17 =sample UR 781+20 (500.7m.) 18 =sample UR 812 (547m.)


19 =sample UR 849 (602.5m) 20 =sample La Paz 712 m (712m) 21 =sample La Paz 886 m (886m) 22 =sample La Paz 989 m (989m) 23 =sample Esm 21 m (1067m)


2 3 4 5 6 7 8 9


I


I


I


I


I


I


I


I


I


I


I
1


I


I


I


I


I










Table 5-6. First (FAD) and last (LAD) appearance datums and abundace peaks (P) for 84 taxa used in graphic correlation. Units are in meters. Tibui section after Gonzalez(1967), T4 section after Rull (1997b).


taxon
Baculamonocolpites "curubensis" Bombacacidites annae Bombacacidites brevis Bombacacidites foveoreticulatus Bombacacidites nacimientoensis Bombacacidites soleaformis Brevitricolpites "microechinatus" Cicatricosisporites dorogensis Cricotriporites "macropori" Cricotriporites guianensis Cricotriporites minutipori Curvimonocolpites inornatus Cyclusphaera "scabratus" Echimonocolpites "tenuiechinatus" Echinatisporis "brevispinosus" Echinatisporis "microechinatus" Echinatisporis "obscurus" Echinatisporis? "cingulatus" Echiperiporites estelae Echitriporites trianguliformis var. "orbicularis" Ephedripites vanegensis Foveodiporites guianensis Foveotricolpites perforatus Foveotricolporites "fossulatus" Foveotriporites hammenii Jussitriporites undulatus Ladakhipollenites rubini Ladakhipollenites simplex Longapertites proxapertitoides var reticuloides L proxapertitoides var. proxapertioides


sp. Pifialerita code FAD LAD
12 696.6 733.7 28 30.6 311.4
29 689.4 30 784.8
31 660.6 775.6
32 784.8
36 214.2 214.2
42 660.6
56 636.6 775.6 57 475.2 475.2 58 715.6 715.6 63 105.3
64 636.6
67 46.8 266.4
71 660.6
72 673.8 689.4 73 30.6 775.6 76 733.7 733.7 80 689.4 775.6
90 660.6
93 79.2 131.4
98 5.4
100 81 266.4 103 689.4 733.7 112 660.6 775.6 131 660.6 775.6 133 715.6 738.3 134 702.9 710.8 149 475.2 775.6 150 105.3 696.6


Regadera P FAD LAD
306
70


264 264

128 128
31
264
31 99


Uribe P FAD
361


LAD
361


Tibui FAD


T4
IAD FAD LAD


36.8


501 501

501 501


261.9


485.5


225


331.1 326.0


547 547


225

128 361 361


712 501


99
306
291 291





291 145 99 145


475 475


215 215
31
145 31


547


521.7 680.5


501 501 250.7


24.5 192.9 261.9

192.9 261.9


547 712 71.2
187.7


471 225


534.9


501 240.4 250.7 471 71.2









Table 5-6--continued.


taxon
Momipites africanus Monoporopollenites annulatus Nothofagidites "huertasi" Perfotricolpites digitatus Perisyncolporites pokornyi Polypodiisporites specious Polysphaeridium sp. A Proxapertites cursus Proxapertites humbertoides Proxapertites magnus Proxapertites operculatus Proxapertites psilatus Psilabrevitricolporites simpliformis Psilamonocolpites grandis Psilaperiporites "pauciporatus" Psilastephanocolporites "psilatus" Psilastephanocolporites fissilis Psilastephanoporites "distinctus" Psilatricolporites "orbicularis" Psilatricolporites "spongiosus" Psilatricolporites crassus Psilatricolporites maculosus Psilatricolporites operculatus Psilatricolporites transversalis Psilatricolporites Iriangularis Racemonocolpitesfacilis Racemonocolpites racematus Retibreviiricolpites "santanderensis" Retibrevitricolpites triangulatus Retidiporites magdalenensis Retimonocolpites "ovatum" Retimonocolpites regio Retistephanocolpires angeli Retisrephanocolporites festivus


Regadera Uribe Tibui T4
P FAD LAD P FAD LAD FAD LAD FAD


99 291
264 264


229.5


138.4 331.1


sp. Pifialerita code FAD LAD
162 30.6 758.6 163 636.6 775.6 165 758.6 766.8 170 689.4 715.6 172 660.6 181 660.6 182 660.6 738.3 184 702.9
185 30.6 766.8 186 710.8
187 30.6 775.6 188 46.8 193 37 266.4 194 311.4
198 660.6 766.8 203 733.7 204 673.8 775.6 207 733.7 758.6 213 715.6 715.6 217 131.4 311.4 218 660.6 219 696.6 220 710.8 710.8 221 234 733.7 222 696.6 234 636.6 235 46.8 46.8 237 710.8 710.8 240 696.6 710.8 245 266.4
246 79.2 247 475.2
255 46.8 311.4 257 689.4


214 31
214 264 291


471 547


471 225

547 418


471 225

547 418


LAD


326.0 684.7


521.7 286.3 303.0


654.0


192.9 247.3
261.9
531.4


215 215


291 31

291 215


31


225 501 361 712


384.5 367.8
534.9


99 128


547 471


23.8 315.9 471 250.7 331.1


145 145


547 547 18.8


445.8


27.8


264


261.9


180 712


187.7 321.5 326.0 99 128 501 501 36.8 308.6


291 753 215
291


LAD









Table 5-6--continued.


taxon
Retistephanoporites angelicus Retitricolpites absolutus Retitricolpites antonii Retitricolpites clarensis Retitricolpitesflorentinus Retitricolpites magnus Retitricolpites saturum Retitricolporites "delicatus" Retitricolporites guianensis Retitricolporites hispidus Retitricolporites irregularis Retitricolporites mariposus Relitricolporites medius Rugotricolporitesfelix Spinizonocolpites "breviechinatus" Spirosyncolpites spiralis Striatricolpites catatumbus Syncolporites lisamae Ulmoideipites krempii Verrutricolporites "reticulatus"


Regadera Uribe Tibui T4
P FAD LAD P FAD LAD FAD LAD FAD LAD
291 315.9 331.1
36.8 282.5

240.4


sp. Pifialerita code FAD LAD
261 738.3 273 738.3 738.3 274 696.6 696.6 275 475.2 276 784.8 277 660.6 758.6 278 196.2 266.4 282 733.7 752.6 294 660.6 295 710.8 296 636.6 297 475.2 475.2 298 636.6 314 689.4 689.4 329 30.6 266.4 333 636.6 336 636.6
344 154.8 154.8 354 266.4
360 636.6


128
128


291
128


291
99 215

31
291 291


27.8 308.6
331.1 277.2


521.7


418 418


367.8
71.2 245.0 303.0 138.4 286.3 684.7

36.8
315.9 331.1 485.5 534.9


180 712 240.4 331.1 286.3 684.7 180 315.9 367.8 684.7
247.3
225 225


128 128










Table 5-7. Fossil events used in the final Composite Section. Event are in composit units FAD=first appearance datums, LAD=last appearance datums, peak=abundace peaks.


taxa
Baculamonocolpites "curubensis" Bombacacidites annae Bombacacidites brevis Bombacaciditesfoveoreticulatus Bombacacidites nacimientoensis Boinbacacidites soleaformis Brevitricolpites "microechinatus" Cicatricosisporites dorogensis Cricotriporites "macropori" Cricotriporites guianensis Cricotriporites minutipori Curvimonocolpites inornatus Cyclusphaera "scabratus" Echimonocolpites "tenuiechinatus" Echinatisporis "brevispinosus" Echinatisporis "microechinatus" Echinatisporis "obscurus" Echinatisporis? "cingulatus" Echiperiporites estelae Echitriporites trianguliformis var. "orbicularis" Ephedripites vanegensis Foveodiporites guianensis Foveotricolpites perforatus Foveotricolporites "fossulatus" Foveotriporites hammenji Jussitriporites undulatus Ladakhipollenites rubini Ladakhipollenites simplex Longapertites proxapertitoides var reticuloides Longapertites proxapertitoides var. proxapertitoides Momipites africanus Monoporopollenites annulatus


code FAD LAD Peak
12 640 733.7 28 30.6 325
29 661 30 640
31 660.6 775.6
32 595
36 214.2 502
42 605
56 580 775.6 57 475.2 730 58 715.6 715.6 63 105.3
64 565
67 46.8 266.4
71 640
72 673.8 689.4 73 30.6 775.6 76 680 733.7
80 668 90 588
93 79.2 312 98 5.4
100 81 310
103 689.4 733.7 112 490 791 131 548 775.6 133 715.6 738.3 134 625 710.8 149 475.2 775.6 475.2 150 105.3 696.6 475.2 162 30.6 758.6 163 568


taxa
Psilabrevitricolporites sinplifornis Psilamonocolpites grandis Psilaperiporites "pauciporatus" Psilastephanocolporites "psilatus" Psilastephanocolporites fissilis Psilastephanoporites "distinctus" Psilatricolporites "orbicularis" Psilatricolporites "spongiosus" Psilatricolporites crassus Psilatricolporites maculosus Psilatricolporites operculatus Psilatricolporites transversalis Psilatricolporites triangularis Racenonocolpitesfacilis Racenonocolpites racematus Retibrevitricolpites "santanderensis" Retibrevitricolpites triangulatus Refidiporites magdalenensis Retinonocolpites "ovatum" Retimonocolpites region Retistephanocolpites angeli Retistephanocolporites festivus Retistephanoporites angelicus Retitricolpites absolutus Retitricolpites antonii Retitricolpites clarensis Retitricolpitesflorentinus Retitricolpites magnus Retitricolpites saturum Retitricolporites "delicatus" Retitricolporites guianensis Retitricolporites hispidus


code FAD LAD
193 37 266.4 194 311.4
198 660.6 766.8
203 625
204 673.8 775.6 207 650 758.6 213 505 715.6 217 131.4 311.4
218 637 219 621
220 705 710.8 221 232 733.7
222 696.6 234 265
235 46.8 715 237 600 710.8
240 245
245 312
246 79.2
247 475.2
255 46.8 685
257 322 261 650
273 322 738.3 274 696.6 696.6
275 475.2
276 265
277 660.6 758.6 278 196.2 266.4 282 590 752.6
294 650 295 490











Table 5-7--continued.

taxa
Nothofagidites "huertasi" Perfotricolpites digitalus Perisyncolporites pokornyi Polypodiisporites specious Polvsphaeridium sp. A Proxapertites cursus Proxaperties humbertoides Proxapertites magnus Proxapertites operculatus Proxapertites psilatus


code FAD LAD Peak
165 640 766.8 170 522 780
172 612 181 615
182 650 738.3 184 702.9
185 30.6 766.8
186 725 214.2
187 30.6 775.6 214.2
188 46.8


Retitricolporites irregularis Retitricolporites mariposus Retitricolporites medius Rugotricolporitesfelix Spinizonocolpites "breviechinatus" Spirosyncolpites spiralis Siriatricolpires catatumbus Svncolporites lisanae Ulmoideipites krempii Verrutricolporites "reticulatus"


code FAD LAD
296 522
297 475.2 475.2
298 322
314 665 725
329 30.6 266.4
333 560 336 562
344 154.8 255 354 610
360 580










Table 5-8. Datums used for calibration of Composite Section. Rio=Paz de Rio section, rubio= Rubio section, Imo=Imo section; Ovim= Ovim section, Benin=Benin well (Germeraad et al ., 1968) Itori=Itori well (Agegoke et al. , 1970, Jan du Chene et al. , 1978)


Rio Rubio Imo Benin Ovim Itori
taxa code FAD LAD FAD LAD FAD LAD FAD LAD FAD LAD FAD LAD
Bombacacidites annae 28 57.7 469.2
Cicatricosisporites dorogensis 42 469.2 746.2 3980 2495
Echiperiporites estelae 80 496.2
Foveotricolpites perforatus 100 92.3 92.3 57.7 469.2
Monoporopollenites annulatus 163 469.2 638.5 730.8 576 2010 5085 1095
Perfotricolpites digitatus 170 469.2 1550
Perisyncolporites pokornyi 172 469.2 746.2 704 704 1030 1030
Proxapertites cursus 184 92.3 188.5 469.2 192 2010 675
Proxapertites operculatus 187 92.3 2010 4025 225
Psilatricolporites crassus 218 496.2 888.5 584.6 738.5 768 4805 450 00
Psilatricolporites operculatus 220 469.2 2320 4096
Retibrevitricolpites triangulatus 240 496.2 719.2 530.8 746.2 576 2010 3420 450 16.5 13.0
Retidiporites magdalenensis 245 407.7 384 225 13.0
Retitricolporites guianensis 294 746.2
Retitricolporites irregularis 296 469.2 530.8 696.2
Striatricolpites catatumbus 336 361.0 530.8 730.8 192 5085 450







79


Nigeria and contained sporomorph information and radiometric dating of a bentonite (Adegoke et al., 1970; Jan du Ch8ne et al., 1978a). Datums for this section are in Table 5-8. These four sections were compared against the Composite Section (CS). The planktonic datums and radiometric age were then projected upon the CS (Fig. 5-14, 5-15, and 5-16).



Discussion

Biostratigraphers should not expect widespread synchronous first and last

occurrences in the stratigraphic record. Many variables like migration, non preservation, barriers, and local extinctions can truncate the geological range of a taxon (Mann and Lane, 1995). Pollen and spores distributions in tropical environments are strongly controlled by the geographic distribution of the plants from which they are coming. However, this fact has not been considered in the palynological zonations proposed so far for the Paleocene-Eocene interval in northern South America. For example, some zones have been based on pollen produced by mangrove elements (Psilatricolporites crassus zone, Germeraad et al., 1968). A zone like that clearly would be controlled by facies, and would lead to the recognition of false "hiatus" in continental areas where mangrove was not present. This may be one of the reasons of the multitude of hiatus proposed during the Eocene in the Colombian-Venezuela region (Colmenares and Terin, 1993). Here, the pollen and spores distribution was analyzed using the technique of graphic correlation. This method dismisses narrative-type scenarios and produces alternative hypothesis that can be expressed in testable forms (Mann and Lane, 1995). Graphic correlation does not make the a priori assumption that first and last appearances in a particular section record speciation and extinction events. By combining the information of multiple sections, the method allows the true stratigraphic range of a taxon to be determined; therefore, the use of an "index" fossil is not necessary as the whole assemblage is being compared. This approach also produces a biostratigraphic framework that constantly can be challenged as







80

800 163 87
cu
184 22-) CS 700 + 0
.-18
600- 336 172
0 163
500

400 - ---P 4 3 0 0 - _ 2 4 5
* 240
0
200

100

0 .................... .............. Imo
0 400 800 1200 1600 200OM240 Imo shale Ameki Ogwashi
-asaba
Planorotalites (Globorotalia) pseudomenardii zone (P4) Morozovella (Globorotalia) velazcoensis/acuta zone (upper P4-P5)

320
Cu
245
CS 310

300

290

280

270 OFAD
+LAD 260

250
(middle P7 240
to middle P4) 240 1 .......... Itori
30 20 10 mo Ewekoro A 54.4+/- 2.7my (middle P7
to middle P4)

Figure 5-14. Line of correlation for Imo section (Germeraad et al., 1968) and Itori well (Adegoke et al., 1970 and Jan du Chene et al., 1978) versus Composite Section. See Table 5-6 for names of the taxa used in graphic correlation.







81


CS


middle P9-P14=

middle P6upper P8






upper P4-


700
c.u.


500 -400300 200 oo-


I0


500


i00


1500 m. 20&) Ovim


Imo shale Ameki

Truncorotaloides rohri zone (middle P9-P14) Morozovella (Globorotalia) formosa
zone (middle P6-P7)
Morozovella (Globorotalia) velazcoensis/acuta zone (upper P4-P5)


middle P9-P14 U


CS


700 600



5


0.
000


4500 4000 3500


ft. 3000


Akata I Ag. Benin


0 FA D +LAD






Benin


Truncorotaloides rohri zone (middle P9-P14)


Figure 5-15. Line of correlation for Ovim and Benin section (Germeraad et al., 1968) versus Composite Section. See Table 5-6 for names of the taxa used in graphic correlation.


2180
172 o

3360 - 0 163
170 0





24

40 0





187


+187



218 o42







82


Benin]


Ovim


middle P9-P14


middle P9-P14 --== = =middle P6-P7 E- --


Imo


P4
Itori
(middle P4+ --- - - to middle P7) Bern

upper P4-P5


upper P4-PS


I-


Composite Section 80
c.u
700 P9-P14 00 ---50.8

P6-P7

- - - - 54.5
-400


300
P4-P5 200


-100


-0-59.2


Figure 5-16. Summary of calibration datums for the Composite Section. See Figures 5-14 and 5-15 for source of information.


-c
o0
E



0
0 w


0
0
cc






83


new information (more sections) is being produced. On the contrary, "traditional" zonations such as the ones currently used in northern South America, are static and authoritative, strongly relying opon one biostratigrapher's interpretation of the chronostratigraphic importance of a given taxa. Graphic correlation was developed by Shaw (1964) and has been successfully used for many authors and specially by Amoco researchers for many years (Carney and Pierce, 1995).

The general sequence of events, first appearance datums (FAD), last appearance datums (LAD), and abundance peaks, of the Composite Section (CS) is similar to those of previous zonations (Table 5-7 for datums, c.u. indicates composite unit). The sequence of Foveotricolpites perforatus LAD (81 composite units c.u.); Retibrevitricolpites triangulatus FAD (245 c.u.); Foveotricolpites perforatus LAD (310 c.u.); Ephedripites vanegensis LAD (312 c.u.); Retidiporites magdalenensis LAD (312 c.u.); Bombacacidites annae LAD (325 c.u.); Cricotriporites guianensis LAD (475.2 c.u.); Foveotriporites hammeni FAD (490 c.u.); Monoporopollenites annulatus FAD (568 c.u.);Cicatricosisporites dorogensis FAD (605 c.u.); Perisyncolporites pokornyi FAD (612 c.u.); Psilatricolporites crassus FAD (637 c.u.); and Rugotricolpitesfelix LAD (725 c.u.) mostly agrees with previous zonations.

However, there are several discrepancies with Germeraad et al. (1968) and Muller et al. (1987) zonations specially within the Eocene. Taxa, which according to these zonations should not be overlapping, are overlapped (e.g., Cicatricosisporites dorogensis and Rugotricolpitesfelix). Most of the taxa ranges in Muller's and Germeraad's zonations abruptly end or begin at time boundaries (Paleocene/Eocene, lower/middle Eocene, and middle/late Eocene). In the Composite Section (CS), the first and last occurrence events are tied to stratigraphy. This produces a higher time resolution and non-congruence in single stratigraphic horizons of most of the first appearance datums (FAD) and last appearance datums (LAD). Therefore, many of the FAD and LAD sequence of events in the CS do not agree with the Germeraad et al. (1968) and Muller et al. (1987) zonations






84


where taxa appear in pseudo-bursts of speciation events (e.g., Paleocene/Eocene boundary with 25 new taxa). This probably is also helped by the higher level of resolution of the CS versus previous zonations. It is also noteworthy the increasing of first occurrence datums above 550 c.u. (probably Eocene, see discussion below) that had been noted already by many authors (Leidelmeyer, 1966; Gonzalez, 1967).

The CS has low sample resolution between 330 and 390 c.u. and between 500 and 600 cu. due to the sterility of most of the samples in the Pifialerita section (upper Arcillas de El Limbo, lower Areniscas de El Limbo Formations), in the Regadera section (upper Cuervos, lower Mirador), and in the Uribe section (upper Lisama, lower La Paz Formations, see Tables 5-3, 5-4, and 5-5). Information for this interval, however was supplied by Tibui section (Gonzalez, 1967). Correlations of these sections against the composite (Figs. 5-11, 5-12), indicate that there is not a significant hiatus associated with the Mirador/Cuervos, La Paz/Lisama, or Arcillas de El Limbo/Areniscas de El Limbo contacts, at least in the localities studied. Many authors since the fifties have associated this contact in Colombia with a major hiatus that would encompass 16 my, the entire early to middle Eocene (Morales, 1958; Schamel, 1991; Dengo and Covey, 1993; Cooper et al., 1995; Ramon and Cross, 1997; Suarez, 1997a; Suarez, 1997b; Villamil and Restrepo-Pace, 1998). This idea is deeply rooted in Colombian literature and nowadays constitutes a "pseudo-dogma". However, an intensive literature search has not given even a single locality with fully documented paleontological information supporting this hypothesis, some localities with palynological information have not registered this hiatus (Gonzalez, 1967 in Catatumbo area, and Colmenares and Teran, 1993 in Maracaibo Basin). It could be possibly that in the files of oil companies exist enough evidence supporting this hiatus; however, the graphic correlation of the three sections studied and the Tibui, Rubio and Paz de Rio sections (Figs. 5-11 to 5-13) does not indicate a major hiatus encompassing 16 my. Julivert (1961) also pointed out the lack of paleontological evidence supporting this hiatus in the middle Magdalena area and conclude that the time-






85


gap, where present, would be isochronous with the accumulation of the Lisama Formation (Paleocene), because Lisama is absent from anticlines axis, and in angular unconformity above Cretaceous sediments in anticline flanks. The time-gap would not be between La Paz-Lisama as previously assumed but during the accumulation of Lisama. I would argue that one of the reasons that is producing the perception of this hiatus is that samples above and below the assumed hiatus are generally sterile for palynomorphs. This would produced an artificial gap in time because of the absence of traditional pollen zones present within the sampling gap. The possibility of an important hiatus is, however, still an open question.

One of the most difficult tasks in biostratigraphy is calibrating the Composite Section (CS) with the geologic time scale. The Paleocene and Eocene epochs and their ages are defined by planktonic foraminifera, calcareous nannoplankton and magnetic polarities. The chronostratigraphy of Berggren et al. (1995b) for the late Paleocene and Eocene is followed here (Fig. 5-17). The planktonic foraminifera zonation is that of Berggren et al. (1995b). Most of the epoch/series and stage/age boundaries of the late Paleocene and Eocene are relatively well established with the exception of the Paleocene/Eocene boundary that still does not have a Global Stratotype Section and Point (GSSP). The Paleocene and Eocene series terms were defined in 1874 and 1833 respectively (Berggren and Aubry, 1998). The boundary awaits determination of a GSSP within the 2 my time span between the top of the Thanetian Stage and the base of the Ypresian Stage. The difficulties in defining the boundary are caused by the multitude of unconformities and facies changes at the base of the type section of Ypresian Stage in Belgium (base of leper Clay of the Belgian Basin that is equivalent to base of the London Clay Formation in London/Hampshire Basin). The base of the Ypresian Stage/Series in these two localities is separated from top of Thanetian Stage/Series (Thanet Beds, London Basin) by an stratigraphic interval where Paleocene/Eocene boundary would be located (Berggren and Aubry, 1998). This interval encompasses from NP10a/b






86


boundary, base of Ypresian (54.37 my) to the top of Thanetian (56.6 my). Several events within this interval are suggested to denote the Paleocene/Eocene boundary (Berggren and Aubry, 1998). Planktonic P5/P6 boundary (54.48 my), N9/N10 boundary (55 my), benthic foraminiferal extinction (55.5 my), and delta13C isotopic excursion (55.5 my). Here, the planktonic P5/P6 boundary (54.48 my) is chosen as the Paleocene/Eocene boundary (Fig. 5-17).

Few elements are available to calibrate the CS. Germeraad et al. (1968) paper stated a number of foraminifera taxa recorded from sections in Colombia and Venezuela (see Fig. 5-2 and text in "previous studies"). Unfortunately, the paper did not indicated the precise stratigraphic position of any of those foraminifera taxa. Therefore, they cannot be used in the graphic correlation methodology. Germeraad et al. (1968) only presented stratigraphic positions of foraminifera from sections in Nigeria. These were the information used to calibrate the CS developed in this study. Germeraad et al. (1968) and subsequent reaearch in Nigeria (Adegoke and Jan du Chene, 1975; Jan du Chene and Salami, 1978; Jan du Chene et al., 1978a; Salami, 1985; Awad, 1994) have noticed floristic similarities between northern South-America and tropical Africa during Paleocene and Eocene times. These authors also have used, to some extent, the Germeraad et al. (1968) zonation. Therefore, correlations with the Nigerian sections probably would provide a general idea of the timing of pollen and spores succession in northern South America until further research in the area is done.

The Imo and Ovim sections contain the Planorotalites (Globorotalia)

pseudomenardii zone that is equivalent to P4 zone of Berggren et al. (1995b), and the Morozovella velascoensis/Morozovella acuta zone that is equivalent to the upper P4 to P5 zones of Berggren et al. (1995b) (see Figs. 5-14, 5-15 and 5-16; taxonomy after Tourmankine and Luterbache, 1985, taxa ranges after Tourmankine and Luterbache, 1985 and Berggren et al., 1995b). When projected in the CS, the foraminifera indicate that the interval P4-P5 is located between composite units (c.u.) 0 to 410 (Fig. 5-16). The








87


Time
(My) Epoch
3233

34
U
35 U
36 37 38 39

40 41 42 43



45

46 47 48 4950 U

51
0
LQ 52 53

54 55

56 57
0 58 59 U

60 61


Plankton
Age zones Chrons



CeO ,-


0 CI


0 Ce
0
U
0


Ce
U a
0~


- -C
Ce
U 0 Ce .0
0 Ce
0 Ce U


P18 =P17 P16 P15




P14 P13


P12


P1


PlO


P9 P7 P6 P5



P4 P3


I






I






i


I


U



I


I


Cl 2r C13n
C 13r
-Clsn:
_CLi
Cl6n c IrC 17n



Cl 8n

C l8r C19r

220n


C20r



22 1n


C21r


C22n
C22r C23n
-C23r C24n


C24r



C25r




C26r


Figure 5-17. Berggren et al. (1995) chronology of the late Paleocene-Eocene epochs. Dashed lines at 55.5 My reflects current opinion on the position of the PaleoceneEocene boundary. Taken at the base of the type Ypresian in Belgian basin or the London Clay in London Basin it position would be at 54.6 to 54.8My.


' '


' ' '






88

position of the Paleocene/Eocene boundary is then tentatively located at c.u. 420, although it could be located in an interval between 410 and 475, because the sample at 477 meters in the Piflalerita section (c.u. 475) contains an assemblage that lack typical late Paleocene taxa as Foveotricolpites perforatus, Retidiporites magdalenensis, and Bombacacidites annae. This late Paleocene age given to the 0-410 c.u., is also supported by the radiometric dating of a bentonite (Adegoke et al., 1970; Jan du Chene et al., 1978a) that yielded an age of 54.4+/- 2.7 million years equivalent to middle P7 to middle P4 planktonic zones (Figs. 5-14, 5-17).

The early Eocene is recognized by the projection in the CS of the Morozovella formosa zone of Germeraad et al. (1968). They did not state how this zone was identified, therefore, I took the conservative approach of considering the total range of M. formosa-formosa, (middle P6 to P7 after Berggren et al., 1995b), as the chronostratigraphic significance of Germeraad et al. (1968)M. formosa zone (Fig. 5-17). Therefore, the early Eocene (zones P5 to P7) would be represented between composite units 420 to 590 (Fig. 5-16).

The uppermost early Eocene and middle Eocene is recognized by the Germeraad et al. (1968) Truncorotaloides rohri zone. They did not state how this zone was recognized, therefore here I take the conservative approach of considering the whole range of T. rohri (middle P9 to P14 after Tourmankine and Luterbache, 1985) to denote the chronostratigraphic significance of the "T. rohri zone". In this scenario the latest early Eocene and middle Eocene would be present above 590 up to 670 c.u. Calibration above 670 c.u. is not possible due to the lack of foraminifera data.

An alternative hypothesis would be to consider the T. rohri of Germeraad

equivalent to T. rohri-M. spinulosa Partial Range Zone (P14) of Berggren et al. (1995b). This hypothesis would indicate an extensive time condensation (-10.8 my), between c.u. 590 and 670, top of P7 to base of P14 (see Figure 5-16). This condensation, however, is not supported by the stratigraphic position of this composite unit (c.u.) level in Uribe,






89

Regadera, Tibui, TI sections (Figs. 5-11 and 5-12, Appendix B), where lithology does not indicate an extensive hiatus. This level in the Pifialerita section is associated with a transgressive surface (see discussion in Sequence Stratigraphy below) and probably some time condensation (Fig. 5-12). Therefore, the possibility of an early to middle Eocene hiatus still exists but further research is necessary to address this specific issue.














CHAPTER 6
SEQUENCE STRATIGRAPHY



Sequence stratigraphic is the study of genetically related facies within a

framework of chronostratigraphic significant surfaces (Van Wagoner et al., 1990). The "sequence" is its basic unit that is defined as a relatively conformable, genetically related succession of strata bounded by unconformities or their relative conformities (Van Wagoner et al., 1990). A parasequence is the building block of a sequence and is defined as a relatively conformable, genetically related succession of beds or bedsets bounded by marine-flooding surfaces or their correlative surfaces (Van Wagoner et al., 1990).

A sequence stratigraphic analysis requires many different types of information (sedimentary, biostratigraphic, seismic) to fully understand the stacking pattern of parasequences in lowstand systems tract (LST), transgressive systems tract (TST); or highstand systems tract (HST), and the recognition of important surfaces (MFS: maximum flooding surface, TS: transgressive surface, and SB: sequence boundary). In this study, I combined three different types of information (palynofacies, paleoecological analysis of palynomorphs, and lithological analysis) to produce a "paleobathymetric" curve (a curve that represents the relative movement of the coastline in relation to a fixed point that is the section studied), and a sequence stratigraphic interpretation for each of the three sections. In the following headings (Palynofacies, Paleoecology, and Lithology), I will present and discuss each type of information. At the end of this chapter (in "Sequence Stratigraphic Interpretation"), they will be combined and a sequence stratigraphic model will be proposed for each stratigraphic section. This analysis does not include a reconstruction of the regional geometry of the entire basin. The purpose here is to produce well-supported stratigraphic hypothesis, with age control, that can be


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MIDDLE PALEOGENE PALYNOLOGY OF COLOMBIA, SOUTH AMERICA: BIOSTRATIGRAPHIC, SEQUENCE STRATIGRAPHIC, AND DIVERSITY IMPLICATIONS By CARLOS A. JARAMILLO A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 1999

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ACKNOWLEDGMENTS First and foremost, I wish to thank my advisor, Dr. David L. Dilcher. His advice, encouragement, constructive criticism, and help were instrumental in the success of this project. I would like to thank the members of my committee Drs. David Hodell, Douglas Jones, Walter Judd, Steven Manchester, and Neil Opdyke for their continuous support. I am grateful to German Bayona for his assistance during the field season. Thanks go to Drs. Fernando Etayo and Tomas Villamil for encouraging me to pursue a Ph.D. I would like to thank Dr. David Jarzen, and Ricardo Holdo for discussion about palynological and statistical matters. The Corporacion Geologica Ares provided valuable logistic support. This study was funded by the National Science Foundation, Colciencias, the Fundacion para la Promotion de la Investigation y la Tecnologfa Banco de la Republica, the Geological Society of America, the American Association of Petroleum Geologists, the American Association of Stratigraphic Palynologists, the University of Florida's College of Liberal Arts and Sciences, the Department of Geology, and the Florida Museum of Natural History. My gratitude goes to Rodolfo Dino from Petrobras, Henry Hooghiemstra from the University of Amsterdam, Roel Verreussel from the University of Utrecht, and Estela de DiGiacomo from Pedevesa, for allowing me to visit their palynological collections. Graham Williams and Jonathan Bujak helped me with the dinocyst identifications. I am also grateful to all the people who helped me during my field season in the towns of Sabanalarga, Uribe-Uribe, and Cucuta. Special thanks go to my parents who have patiently supported me through the many years of my schooling, and to my wife, Maria Ines Barreto, who has kept me alive. ii

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TABLE OF CONTENTS page ACKNOWLEDGMENTS ii LIST OF TABLES v LIST OF FIGURES vi ABSTRACT ix CHAPTERS 1 INTRODUCTION 1 2 OBJECTIVES 4 3 MATERIALS AND METHODS 5 4 REGIONAL GEOLOGICAL SETTING 17 5 BIOSTRATIGRAPHY 20 Previous Studies 22 Results 44 Discussion 79 6 SEQUENCE STRATIGRAPHY 90 Palynofacies 91 Previous Studies 91 Results 92 Discussion 107 Paleoecology Ill Previous Studies Ill Results 112 Discussion 119 Lithology 127 Previous Studies 127 Results 136 Sequence Stratigraphy Interpretation 148 Previous Studies 148 Results 157 Discussion 160 in

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7 DIVERSITY 176 Previous Studies 178 Results 179 Discussion 189 8 CONCLUSIONS 200 APPENDICES A TAXONOMIC DESCRIPTIONS 205 B LITHOLOGICAL DESCRIPTION OF THE PINALERITA SECTION 353 C LITHOLOGICAL DESCRIPTION OF THE REGADERA SECTION 379 D LITHOLOGICAL DESCRIPTION OF THE URIBE SECTION 386 REFERENCES 397 BIOGRAPHICAL SKETCH 417 i v

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LIST OF TABLES Table page 3-1. Organic matter classification 12 5-1. Pollen and spores named from the Paleogene of northern South America 24 5-2. Botanical affinities for fossil sporomorphs from northern South America 31 5-3. Palynomorph distribution in samples from the Pinalerita section 56 5-4. Palynomorph distribution in samples from the Regadera section 67 5-5. Palynomorph distribution in samples from the Uribe section 70 5-6. First and last appearance datums and abundace peaks for 84 taxa used in graphic correlation 73 5-7. Fossil events used in the final Composite Section 76 58. Datums used for calibration of Composite Section 78 61. Palynodebris count data (in %) for the Pinalerita section 101 6-2. Palynodebris count data (in %) for the Regadera section 103 6-3. Palynodebris count data (in %) for the Uribe section 105 6-4. Previous paleoecological interpretations for sporomorphs found in this study 114 65. Abundance of selected taxa used in paleoecological analysis 116 71. Sporomorph species shared by Africa, Gulf Coast, and Caribbean/Central America with Northern South America 191 v

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LIST OF FIGURES 31. Geologic map of Colombia showing the three sections studied 6 41. Sedimentary tectono-stratigraphic provinces of Colombia 19 51 . Range chart for Angiosperm fossil pollen in Northern South America 23 5-2. Ranges of foraminifera used to calibrate Germeraad palynological zonation... 36 5-3. Comparison of Germeraad, Regali and Muller zonations 42 5-4. First round of correlation. Pinalerita (Reference Section) versus Regadera 46 5-5. First round of correlation. Composite Section versus Tibui 47 5-6. First round of correlation. Composite Section versus T4 and Uribe sections ... 48 5-7. Second round of correlation. Composite Section versus Regadera 49 5-8. Second round of correlation. Composite Section versus Tibui 50 5-9. Second round of correlation. CS versus T4 and Uribe sections 51 5-10. Second round of correlation. Composite Section versus Pinalerita 52 5-11. Correlation for well T 1 , Regadera, and Tibui sections versus CS 53 5-12. Correlation for Uribe and Pinalerita sections versus Composite Section 54 5-13. Correlation for Rubio Road and Paz de Rfo sections versus CS 55 5-14. Line of correlation for Imo section and Itori well versus CS 80 5-15. Line of correlation for Ovim and Benin section versus CS 8 1 51 6. Summary of calibration datums for the Composite Section 82 517. Berggren et al. (1995) chronology of the late Paleocene-Eocene epochs 87 61 . Palynofacies of Pinalerita section 94 6-2. Palynofacies of Regadera section 95 vi

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6-3. Palynofacies of Uribe section 96 6-4. Average linkage cluster analysis of palynofacies in the Pinalerita section 97 6-5. Organic matter content of each of palynofacies group, Pinalerita section 98 6-6. Cluster analysis of palynofacies in the Regadera and Uribe sections 99 6-7. Content of palynofacies groups for Regadera and Uribe sections 100 6-8. Non-metric multidimensional scaling analysis 113 6-9. Paleoenvironmental interpretation of Pinalerita section 124 6-10. Paleoenvironmental interpretation of Regadera section 125 6-11. Paleoenvironmental interpretation of Uribe section 126 6-12. Schematic representation of the major divisions of fluvial environment 137 6-13. Schematic representation of the major divisions of delta environment 138 6-14. Schematic representation of the major divisions of estuary environment 139 6-15. Sequence stratigraphic interpretation for Pinalerita section 140 6-16. Sequence stratigraphic interpretation for Regadera section 141 6-17. Sequence stratigrphic interpretation for Uribe section 142 6-18. Cooper and Cazier sequence stratigraphic models 150 6-19. Previous sequence stratigraphic models for Colombian Llanos foothills 155 6-20. Relationship of lithospheric flexure to accomodation in foreland systems 162 6-21. Sequence stratigraphy and subsidence profile across foreland basins 163 6-22. Middle Magdalena Basin 166 6-23. Sequence stratigraphy interpretation for the Llanos foothills, Colombia 167 6-24. Simplified map of the Llanos foothills, Colombia 169 6-25. Schematic location of Pinalerita section in a incised-valley filling 171 6-26. Regional correlation of sections with palynological information 173 627. Lithostratigraphy of sections with palynological information 175 71. Diversity analyses. A. DCA B. -loge(Simpson index) 181 7-2. Rarefaction curves for Pinalerita samples 182 vii

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7-3. Rarefaction curves for highstand systems tract samples from Pinalerita 183 7-4. Rarefaction curves for transgressive systems tract samples from Pinalerita 184 7-5. Diversity analyses. A. Standing diversity. B. FAD and LAD rates 185 7-6. Diversity analyses excluding single-occurrence taxa 187 7-7. Diversity analyses. A. FAD/LAD proportions. B. floras 188 7-8. Paleogeographic map of the early middle Eocene 190 viii

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Abstract of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy MIDDLE PALEOGENE PALYNOLOGY OF COLOMBIA, SOUTH AMERICA: BIOSTRATIGRAPHIC, SEQUENCE STR ATIGRAPHIC , AND DIVERSITY IMPLICATIONS By Carlos A. Jaramillo August 1999 Chairman: David L. Dilcher Major Department: Geology The late Paleocene-early Eocene interval is characterized by a long period of global warming that culminated with the highest temperatures of the Tertiary. This time interval is associated with plant extinctions and a subsequent increase in plant diversity in mid and high latitudes. However, data from tropical regions remain largely unknown. This time interval is also of strategic interest in northern South America because most oil reservoirs occur in Paleogene strata where detailed chronostratigraphy is necessary to develop a clear understanding of stratigraphy and structural geology. I analyzed the palynostratigraphy of three areas in the Colombian Eastern Andes (northern Middle Magdalena, Llanos Foothills, and southern Catatumbo) with the aim of achieving three major goals: a) to produce a time-framework using pollen, spores, and dinoflagellates; b) to develop a sequence stratigraphic interpretation for each section using palynofacies, paleoecology, and lithofacies; and c) to look for patterns of pollen and spores diversity through the late Paleocene-Eocene interval. A biostratigraphic framework was built using graphic correlation. Dating sections indicate that there is not a significant time gap encompassing the early and middle Eocene in ix

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all of Colombia as previous authors had interpreted. Also, it is clear that formational boundaries of the Paleocene-Eocene formations do not correspond to epoch boundaries and cannot always be considered as chronostratigraphic surfaces. Sequence stratigraphic interpretations of each section indicate that it is not possible to establish a single sequence stratigraphic model for the three sections because they were in three different basins, isolated from each other, and with different subsidence histories, sediment sources, and stratal architecture. However, there are two events with regional significance: an earliest Eocene sequence boundary, and an early middle Eocene flooding surface. The pollen/spores record indicates a relatively large extinction at the end of the Paleocene and a subsequent increase in diversity during the early and early middle Eocene reaching levels higher that those of the late Paleocene. This extinction and subsequent increase in diversity may be correlated with the late Paleocene Thermal Maximum and Eocene Thermal Maximum, respectively. This demonstrates that variability in tropical climate may have played an important role in the development of plant diversity in the neotropics.

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CHAPTER 1 INTRODUCTION Colombian stratigraphy is mainly composed of Tertiary continental sedimentary rocks. These strata are in structurally complex areas related to the Pliocene Andes uplift further complicating an adequate understanding of the Tertiary stratigraphy. For the last 60 years, intensive geological exploration of Colombian Tertiary rocks has been carried out. Most of this work has been related to oil exploration. Unfortunately, only a small fraction of this information has been published. The Paleocene-Eocene history of northern South America has been the focus of many researchers since the 1950s (Van der Hammen, 1954; Gonzalez, 1967; Muller et al, 1987). Still, this time interval remains poorly known and more detailed geologic research is necessary. Important large-scale events developed during the Paleogene such as the Eocene Thermal Maximum (Miller et al, 1987), the Andes uplift process (EtayoSerna et al, 1983), and the initial closure of the Tethys. More information on those subjects from neotropical areas is necessary for an adequate understanding of them. The Paleogene history of northern South America is also important regionally because the most important hydrocarbon reservoirs in the region are located in Paleocene and Eocene continental rocks. These reservoirs are frequently located in zones with high structural complexity where an excellent biostratigraphic framework is crucial toward understanding the stratigraphy, defining oil-bearing structures, and planning new exploration targets. Three subjects in need of more intensive research are evident in the geology of this area: lack of a high-resolution chronostratigraphic framework, lack of basin-focused sequence stratigraphic models, and the unknown effects of the Eocene Thermal 1

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2 Maximum on tropical vegetation. These three problems could be addressed using fossil data coupled with stratigraphic analyses. The most abundant fossils present in the Paleogene sediments of continental Colombia are palynomorphs and particulate organic matter. The word "palynomorph" is used here to indicate pollen, spores, and dinoflagellates; "sporomorph" indicate pollen and spores, while "palynofacies" indicates the assemblage of particulate organic matter (Traverse, 1988). Relatively little published information exists on Colombian palynology; this may be due to the confidentiality of information used by various oil companies operating in the area. However, previous palynologic studies in the region (Gonzalez, 1967; Germeraad et al, 1968) reported highly diverse and abundant pollen/spores assemblages and showed that sporomorphs are the most reliable biostratigraphic and paleoecological tool in terrestrial Paleogene strata of Colombia. One of the major problems in integrating geologic information produced in neotropical areas, especially Colombia, with the rest of the world is the lack of a truly high resolution chronostratigraphic framework. For the last 30 years, a local system for placing events in a temporal order has been developed in the tropics. This system for the Paleocene-Eocene interval relies on pollen and spores because they are the most abundant fossils in continental deposits accumulated during this time. However, this system has a low resolution for the Paleocene-Eocene and it is poorly correlated with the international time scale. This time scale provides a single universal reference standard for dating rock strata or events in earth history with respect to the passage of geologic time (Berggren et al, 1995a). In other words, what tropical American geologists often call "late Paleocene", "early Eocene", etc., must be taken with caution, and be considered an informal name that does not bear exactly the same meaning as in the standard geologic time scale. A high resolution chronostratigraphic framework calibrated with the geologic time scale is urgently needed. Only then, can we truly start to use and integrate the geologic information produced in neotropics with the rest of the world.

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3 An adequate understanding of the pollen and spores distributions as well as the facies control on their distributions require a stratigraphic understanding of the rocks containing them. Sequence stratigraphy has become the most reliable tool for studying strata in clastic sedimentary basins. Sequence stratigraphy is the study of genetically related facies within a framework of chronostratigraphically significant surfaces (Van Wagoner etal, 1990). This modern approach is widely used to study the hierarchical arrangement and spatial distribution of sedimentary deposits. Sequence stratigraphy was done using palynofacies, palynomorph paleoecology, and lithological analyses. The sequence stratigraphy analysis provided hypotheses for the general patterns of strata distribution and the geographical extent of transgressive and regressive episodes. The effects of the Eocene Thermal Maximum on tropical vegetation are still unknown, but important for a full understanding of the climate and its effects on biota during this unique time in earth's history. One the best tools to study tropical vegetational changes are pollen and spores (Traverse, 1988). Pollen and spores provide a more continuous record of vegetational change than can be had from megafossils, particularly in tropical areas where megafossil plant remains are usually not well preserved. Large climatic variations in terrestrial tropical environments could lead to changes in vegetation that would be recorded by the fossil record of pollen and spores. In the present study the palynomorph distributions and palynofacies across the late Paleocene-Eocene in the eastern Andes of Colombia are presented with the aim of producing high-resolution biostratigraphy, proposing sequence stratigraphy models for the area, and identifying any changes in pollen and spores diversity across the Eocene Thermal Maximum.

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CHAPTER 2 OBJECTIVES This project was undertaken to analyze the palynological biostratigraphic distribution and sequence stratigraphy of three Paleogene sections in the Eastern Andes of Colombia (Fig. 3-1). The main objectives of this study were: 1 . To complete a detailed taxonomic analysis of palynomorphs present in these sections. 2. To build a high resolution biostratigraphic framework for the late PaleoceneEocene interval based on the occurrence and abundance of these palynomorphs. 3. To use palynofacies, palynomorph paleoecology, and lithofacies to propose a preliminary sequence stratigraphy model for each section. 4. To analyze the various patterns of sporomorph (pollen and spores) diversity throughout the middle Paleocene-Eocene of the Eastern Andes of Colombia. These assemblages also were compared to palynofloras in Central America, U.S. Gulf Coast, and tropical Africa during the Paleocene-Eocene. 4

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CHAPTER 3 MATERIALS AND METHODS Three stratigraphic sections were studied in the Eastern Andes of Colombia (Fig. 3-1). The first section is located in the Llanos Foothills, along Pinalerita creek near Sabanalarga, 73° 1' W 4° 54' N, where the Paleogene sequence comprises, from older to younger, the Barco-Cuervos Group (180 m), the oil-rich Mirador Formation (70 m), and the San Fernando Formation (300 m). The second section occurs in the eastern middle Magdalena Valley, along the Rio Negro river, near Uribe, 7° 20N 73° 20W. The third section is located in the Catatumbo area, south of Cucuta, Near La Donjuana, along the Regadera Creek, 72° 37' W 7° 42' N. These sections were measured and described in detail (scale 1:100), recording major physical and biogenic sedimentary structures. The Jacob's staff method was used to measure the sections (Miall, 1984). This method allows for high resolution in sampling and detailed descriptions of stratigraphic sections. A staff was constructed of a 1 .5m wooden rod, with a Brunton compass attached to the tip. The clinometer of the compass was preset at the measured structural dip of the strata in the section, thus the staff can be used to measured the stratigraphic thickness of the section. The staff was always positioned perpendicular to the bedding plane. A consecutive number was marked on the rock with red paint as the measuring of the section advanced upward in the section. These numbers were used as a reference system for describing the section and collecting samples for palynological processing. Rock samples were collected at five to ten meter intervals, for palynologic purposes, a reasonable sampling interval given the thickness of the analyzed sections (averaging 700m/section). 5

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0 100 200 300 400 600|
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7 The palynologic samples were prepared by the standard procedure of digesting sample in HF and HC1 acids, separating organic matter by heavy liquids, and oxidizing with Schultz solution (Traverse, 1988). This method was specifically modified by Russ Harms from Global Geolab, who prepared most of the samples (Global Geolab 729B15th Street S.W., Medicine Hat, Alberta Tl A 4W7, Canada). Twenty-five grams of sample were placed in a 250 ml polypropylene beaker along with a Lycopodium tablet. The Lycopodium tablets were used to have absolute concentrations of pollen per gram of sediment (Traverse, 1988). The specific weight for each sample was measured and recorded. A 10% solution of HC1 was then added and left, generally overnight, allowing carbonates to dissolve. The HC1 was decanted and washed 3 times with distilled water to remove remaining calcium ions that can flocculate when HF is added. Then, 70% HF was added to the sample. The sample was agitated for 4 hours until digestion was completed. The digested sample was poured into a 50 ml. polypropylene test tube and centrifuged for five minutes at 2000 rpm. The top 3/4 was then decanted, and distilled water was added while vortexing and the sample was centrifuged for two minutes. Distilled water was added until the solution was neutral. The next step consisted of adding 5 ml of Darvan, vortexing while adding distilled water and centrifuging for one minute at 2000 rpm. This washing/centrifuging was repeated until the fine clastic material was removed (3 or 4 times). A few drops of concentrated HC1 were added for a better heavy liquid separation, vortexing while adding water and centrifuging for 4 minutes. The heavy liquid separation was done using ZnBr2 (gravity 2.0). Twenty-five ml of ZnBr2 were added to the sample, which was then vortexed thoroughly. The test tube was placed in an ultrasonic bath for ten seconds. Samples were allow to sit for ten minutes before centrifuging for 15 min. at 2000 rpm. The floating part was then poured off into another 50 ml tube, and washed and centrifuged three times for 2 min. at 2000 rpm. The residue was then transferred to a 20 ml glass tube and a first slide for palynofacies analysis was made. The residue was examined for the amount of oxidation

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8 required. Three ml of Schultz solution were poured in the tube with the residue, vortexed, and placed in a hot water bath for 4-12 min. Schultz was removed and the samples washed three times until the solution was neutral. A 10% NH4OH solution was then added and placed in a hot water bath for 2 minutes. The sample was washed and centrifuged three times, was then sieved using a 7um nitex screen cloth. The sieved fractions were pipetted off and mixed in one drop of polyvinyl alcohol with a glass stirring rod. When the polyvinyl was dry, one drop of clear casting resin was added and the coverslip was turned and sealed. Permanent curing occurred in one hour. A Carl Zeiss light microscope (Scope 2, #431 1267, Paleobotany Laboratory, Florida Museum of Natural History) was used for palynologic analyses. At least one complete oxidized slide per sample was scanned with a 40x Zeiss planapochromatic objective and 300 palynomorphs per slide were counted when possible. Examination of the fossil taxa was done using a lOOx Zeiss oil immersion planapochromatic objective. Slides are deposited in the Paleobotanical collection of the Florida Museum of Natural History. Identification was done through comparison with published photographs and descriptions, and the holotype material in the palynological collections of University of Amsterdam (Holland), Petrobras in Rio de Janeiro (Brazil), and Pedevesa in Caracas (Venezuela). I attempeted to consult the holotypes of the collections of Enrique Gonzalez in Venezuela and Gustavo Sarmiento in Colombia. However, these collections could not be observed because they are poorly preserved and inaccessible (Gonzalez, personal communication), and have been misplaced in the Ingeominas, Bogota (Sarmiento, personal communication). Many of the holotypes I observed were badly damaged, especially those described before 1970, and I had to rely on the published descriptions and photographs. Published papers on the U.S. Gulf Coast, Central America and tropical Africa were used as the main sources of the comparative study between the Paleogene of Gulf

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9 Coast, Colombia, and Africa Palynoflora of northern South America was compared with assemblages from U.S. Gulf Coast, Central America and tropical Africa (Van HoekenKlinkenberg, 1966; Germeraad etai, 1968; Elsik, 1968a,b, 1978; Graham and Jarzen, 1969; Srivastava, 1972; Tschudy, 1973; Elsik, 1974; Elsik and Dilcher, 1974; Adegoke and Jan du Chene, 1975; Potter, 1976; Graham, 1977, 1985, 1993, 1995; Jan du Chene and Salami, 1978; Salard-Cheboldaeff, 1978, 1979, 1990; Jan du Chene etai, 1978a,b; Frederiksen, 1980; Martinez-Hernandez et al, 1980; Potter and Dilcher, 1980; Medus, 1982; Tomasini-Ortiz and Martinez-Hernandez, 1984; Mebradu etai, 1985; Salami, 1985; Schrank, 1987; Frederiksen, 1988; Ventatachala etai, 1988; Westgate and Gee, 1990; Oloto, 1992; Awad, 1994; El Beialy, 1998). A time-framework based on the stratigraphic distribution of palynomorphs was developed, using graphic correlation (Shaw, 1964; Edwards, 1984; Edwards, 1989). This is a method of correlating fossil occurrences based on interpretation of graphic plots of first and last appearances of taxa. This is a powerful method because it does not assume a priori that first and last appearances of chosen taxa are synchronous, as the traditional biostratigraphic zonations do. It also allows the production of high-resolution chronostratigraphic frameworks (Pasley and Hazel, 1995; Jaramillo and Oboh, 1999). The two most complete sections were plotted against each other and last and first appearances of all taxa presented in both sections were then compared and plotted (see Chapter 5). A line of correlation was then plotted. The ranges of the taxa were compared with the correlation line and extended up and down section when necessary producing a Composite Section. This Composite Section was then compared with additional sections in the same way. The process was repeated several times until the range of each taxon was stable and did not extended up or down anymore. The final result was a Composite Section that contained the longest range possible for each taxon. This method, however, tends to artificially extend taxon ranges, but this artifact is usually balanced by the variations in sample spacing and probability of finding particular taxa in all possible

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10 samples (Edwards, 1984). The units of this Composite Section are composite units that represent time. They were then calibrated against the geologic time table using foraminiferal datums and radiometric datings. Palynofacies analyses were only undertaken with non-oxidized slides. The oxidation process alters the natural colors of dispersed organic matter (palynodebris) and destroys certain organic matter types, such as structureless amorphous material (Traverse, 1988). At least 300 organic particles were counted per slide. In the absence of a standard palynofacies classification system, one adapted from Lorente (1986), Van Vergen et al. (1990), Oboh (1992), and Jaramillo and Oboh (1999) was used This system classifies dispersed organic matter based on morphological differences seen under a light microscope. The classification scheme is outlined below (see also Table 3-1). a. Aquatic organic matter that comprises the following: a.l Structureless amorphous material. They are gel-like and exhibit a "clotted" appearance (Tyson, 1995). a. 2 Dinoflagellates and foraminiferal wall linings. Most fossil dinoflagellate cysts indicate marine environments (Evitt, 1985). b. Terrestrially derived material that comprises: b. 1 Structureless material b.1.1 Resins. Unstructured amber-color fragments. b.1.2 Black debris. Opaque particles without internal structure, and usually angular shape. Sometimes called charcoal, black wood, or inertinite. b. 1.3 Yellow-brown material. Structureless particles of yellow to light brown color. This material could be attributable to highly degraded herbaceous material b.1.4 Black-brown material. Unstructured dark brown material, which could be attributable to highly degraded woody material. b.2 Structured material:

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11 b.2.1 Cuticles. Cuticles are extra-cellular layers covering the epidermis of higher plants. Well preserved showing clear structure of epidermal cell outlines. b.2.2 Plant Tissue. This group includes all kinds of plant tissue material, with the exception of cuticles and well-preserved woody material. Collenchyma and parenchyma cells are included in this group. b.2.3 Woody material. Particles with brown color, sharp angular edges and discernible cellular structure. b.2.4 Pollen and spores. b.2.5 Fungi. This group includes all fungal remains such as hyphae, fruiting bodies, and fungal spores. Fluorescence was used for distinguishing between amorphous marine and degraded terrestrial organic matter. Marine amorphous is fluorescent, while the terrestrial amorphous is not fluorescent (Lorente, 1986). Palynofacies data were analyzed using multivariate statistical techniques. A Euclidean-distance cluster analysis with average linkage was performed on the palynodebris percentage data and used to develop a palynofacies model, which was then correlated with changes in depositional environments. The Euclidean distance is especially designed to work with continuous or ratio scales (SYSTAT, 1992). Moreover, the linkage averages all distances between pairs of objects in different clusters and decides how far apart they are (Sokal and Michener, 1958). Paleoecological analysis of palynomorph abundace distribution was done using multivariate statistical techniques. Other methods as the Nearest Living Relative are very difficult to apply with pollen and spores in pre-Oligocene sediments (Traverse, 1988), although with a few exceptions (e.g., Spinizonocolpites pollen that is a close relative of extant Nypa, a mangrove palm of South East Asia, Germeraad et ai, 1968). The use of multivariate statistical techniques such as Principal Component Analysis, Multidimensional Scaling, or Cluster Analysis relies on the basic assumption that

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12 Table 3-1. Organic matter classification (adapted from Lorente 1986; Van Vergen et al ., 1990; and Jaramillo and Oboh, 1999). Category Palynodebris Description Aquatic Structureless amorphous Gel-like and exhibit a "clotted" appearance (Lorente, 1986) (structureless material Aquatic Dinoflagellate cysts and Marine microphytoplankton and chitinous (Structured) foraminiferal wall linings internal linings of foraminifera; linings usually spirally-coiled Terrestrial Resins Unstructured amber-color fragments normally (Structureless) derived from stem tissues of gymnosperms Black debris Opaque particles without internal structure; have sharp angular edges or are lath-shaped; called black wood, charcoal and/or inertinite by several workers Yellow-brown fragments Structureless particles of yellow to light brown color attributed to highly degraded herbaceous material Black-brown fragments Unstructured dark brown material, which is attributed to highly degraded woody material Terrestrial Cuticles Cutin layer covering the epidermis of higher plants; (Structured) well preserved and showing epidermis outline Plant Tissue This group includes all other herbaceous material, with the exception of cuticles; collenchyma and parenchyma are included here Woody material Brown particles with sharp angular edges and discernible cellular structure Pollen and spores Spores belonging to pteridophytes and pollen of gymnosperms and angiosperms Fungi This group includes all fungal remains, such as hyphae, mycelia and non-embryophitic spores

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13 pollen/spores that co-occurred in the same samples lived in similar environments, and that statistical parameters evaluate how strong a given co-occurrence is. This approach allowed testing of previous hypotheses for specific paleoenvironments. In addition it provided new hypotheses of palynomorph-environment relationships that can be tested in future studies. The choice of which multivariate analysis to perform on any dataset depends upon the structure and noisiness of the data, the specific question being addressed, and the philosophy behind the study (Kovach, 1989). While considering a problem similar to the one being addressed in this study, Kovach (1989) analyzed a noisy and non-normal dataset, to relate species distribution to a terrestrial-marginal marine gradient, as well as to infer what groups characterized each environment. He found that the best method, which provides an unambiguous answer to the question (Pielou, 1984), was the Spearman rank-order coefficient performing a multidimensional scaling (MDS) analysis. Spearman is a non-metric, quantitative similarity measure in which correlations are made based on the rank-order of the abundances rather than absolute values. Thus, variations in abundance due to noisy data or closure effect do not strongly affect this coefficient (Kovach, 1989) as with metric coefficients. It is effective in paleoecological studies because it places more weight on elements that are farther apart, while close ranks have little affect on the correlation (Sokal and Rohlf, 1981). Multidimensional scaling (MDS) is a multivariate statistical technique that is designed to construct a "map" showing the relationships between a number of objects, given only a table of distances between them (Manly, 1994). It makes no assumption of normality or linearity of the data (Kovach, 1989). It bases the ordination on the rank-order of the elements of the similarity matrix, rather than their absolute values. The basic assumption is that the greater the similarity between two objects, the closer they should be to each other in the ordination (Kovach, 1989). A value, called stress, measures the fitness of ordination to original similarities, the lower the value the fittest ordination. This method requires in

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14 advance the number of dimensions to be used. Using the wrong number of dimensions, however, can distort the results, but generally using 2 or 3 dimensions show little distortion of this sort (Kendel and Orlocci, 1986). MDS can identify major terrestrial-marginal marine gradients along the first and second axes, and seems to be least vulnerable to distortion from high beta diversity, nonnormality, and non-linearity (Kovach, 1989). In this study, MDS analysis was performed on a subset of data from the original distribution range charts. Palynomorphs with high abundances and those with recognized paleoenvironmental significance were selected for this analysis. Sequence stratigraphic analyses for each section involved the integration of palynofacies, palynomorph paleoecology, and lithological data. They were combined to identify major depositional environments for the three sections. Key surfaces, (maximum flooding surfaces, sequence boundaries, and transgressive surfaces) were identified based on the stacking patterns of interpreted sedimentary environments. Then, systems tracts and sequences were recognized. Because of the limited number of proposed sections, this study was not intended to reconstruct a regional geometry for study areas. Rather, the main goal in proposing a sequence stratigraphic study was to provide a hierarchical framework of depositional environments, that could be used to recognize major relative sea level changes during the time interval studied. Sequence stratigraphy terminology and techniques followed that of Van Wagoner et al. (1990). The suggestion by Rosenzweig (1995) of using the word "diversity" in its original meaning of denoting number of species (called richness in the literature) is followed in the analysis of pollen/spores diversity. Patterns of pollen and spores diversity were analyzed using several methods: Rarefaction, a method used to compare the diversity of different samples taking into account sampling density (Raup, 1975). Small number of species in a sample can be an artifact of the number of grains counted in the sample. Rarefaction is a method that addresses this problem. It is an interpolation technique

PAGE 25

15 making it possible to estimate how many species would have been found had the sample been smaller than it actually was (Raup, 1975). In this form, diversity from small and large samples can be compared with each other. Rarefaction has several limitations: collections to be compared should be taxonomically similar, they must also be obtained by using standardized sampling and analytic procedures, they should derive from similar habitats (all from similar lithologies when possible), and rarefaction must be restricted to interpolation of values not greater than the number of individuals of the parent collection (Tipper, 1979). The hypothesis under test is that rarefaction curves being compared refer to collections drawn from same population (population of diversities, not species); the alternative hypothesis is that the populations differ in their diversities (Tipper, 1979). Two populations composed of different species, then, could have similar rarefaction curves indicating that their diversities are similar. Rarefaction curves were calculated with the Rarefaction calculator developed by C. Krebs and J. Brzustowski (http://www.biology.ualberta.ca/jbrzusto/rarefact.html #Top) using the Hurlbert formulae to calculate number of species and Simberloff formulae to calculate the variance. Bootstrap was used to determine the average of number of species/sample for Paleocene and Eocene strata regardless the number of observed samples. Bootstrapping constructs estimates of frequency distributions for use in conducting statistical tests (Gilinsky, 1991). The mean diversity was calculated for a number of samples randomly selected with replacement from two datasets: seven samples from the Paleocene and 13 from the Eocene. This procedure was repeated 4999 times, and then average and confidence intervals for each time interval were calculated and compared. This analysis was done in MetaWin 1.0 with the help of Ricardo Holdo (University of Florida). The range-through method (Boltovskoy, 1988) was used to estimate standing diversity. This method assumed that a taxon is present in a sample if the taxon is present in samples below and above the sample examined. This method takes into account facies-related fossils and differences in capture probability for each taxon. The method

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16 underestimates diversity for intervals at the beginning and end of a section, since there are not more samples that allow to extend ranges of rarer species (Boltovskoy, 1988). The overall floral similarity throughout the section was observed using detrended correspondence analysis (DC A) developed by Hill and Gauch (1980). The ordination was performed on the presence-absence data that already had range-through extensions. Samples with less than 20 grains were eliminated from analysis. DCA summarizes variation in the composition of the assemblages in a small number of dimensions (Wing, 1998). This method assumed that cases come from a gradient in which different variables (in this case taxa) characterize different parts of the gradient making it particularly well suited for distinguishing single, major gradients in the first axis (Kovach, 1989). DCA analysis were performed in MVSP 3.0 statistical software developed by Warren Kovach (http://www.kovcomp.co.uk/mvsp/). The unbiased Simpson index (SI=Z(ni(ni-l)/N(N-l)), N=number of individuals in sample, ni=number of individuals of species i in the sample) was calculated to estimate underlying diversity independently of sample size (Rosenzweig, 1995). This index is free from influence of size of sample, it is adequate to estimate diversity of small samples, and when used as -Ln(SI) it increases as the number of species does (Rosenzweig, 1995). This index was calculated using MVSP 3.0 statistical software. Palynomorphs other than pollen and spores were excluded from all the analysis.

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CHAPTER 4 REGIONAL GEOLOGICAL SETTING Colombian geology has been complicated by uplift attributed to the Andean orogeny that began during the late Cretaceous and was most active during the Pliocene (Van der Hammen et al, 1973). In general, sedimentary rocks comprise 70% of all the rocks in Colombia. Forty percent of the outcropping sedimentary strata are Cretaceous, approximately 55% are Tertiary and Quaternary, while 5% are Paleozoic, Triassic and Jurassic (Etayo-Serna et al, 1983). The sedimentary rocks can be found in ten tectonostratigraphic provinces (Etayo-Serna et al, 1983) that can be seen in Figures 3-1 and 4-1. Paleozoic sedimentary and metamorphic rocks, Triassic red beds and marine limestones, and Jurassic tuffs constitute the basement onto which Cretaceous rocks onlapped (Cediel et al, 1981). The late Jurassic-Cretaceous sea first inundated the northwestern Andean Basin possibly through a western corridor situated in the area that is now Central Colombia at the latitude of Bogota during the Titonian-Berriasian. Subsequently this sea extended into most of southern and northern Colombia (Etayo-Serna et al, 1976). Cretaceous facies have been interpreted as representing marine environments of deposition, especially during the Turonian to Campanian interval (Etayo-Serna, 1979; Barrio and Coffield, 1992). Tertiary rocks accumulated in alluvial plain to littoral environments (Etayo-Serna et al, 1983) with the exception of the marine strata of the Atrato Basin and Lower Magdalena Valley (Galvis, 1980; Duque Caro, 1990). Colombia has undergone a complex history of compressional tectonic events that have produced a mix of superimposed structures (Dengo and Covey, 1993). The Eastern Cordillera (Figs. 3-1 and 4-1) was uplifted throughout the Tertiary with a late intense pulse during the Pliocene-Pleistocene (Van der Hammen et al, 1973), and is bounded by 17

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18 thrust faults systems on its eastern and western margins. Eastern faults dip westward (Guaicaramo thrust system) and western faults dip eastward (Honda-Bituima thrust system), thus structurally creating a large "pop-up" feature that uplifted the Eastern Cordillera (Irving, 1975). Colombian stratigraphic nomenclature has been complicated by the fact that several authors and oil companies have used different names for the same lithostratigraphic units, or the same name for different lithostratigraphic units (Montes et ai, 1993). A recompilation of published information (Montes et ai, 1993) has revealed that the lack of field data and the disorder in stratigraphic nomenclature have resulted in weak tectono-stratigraphic interpretations. These inconsistencies have made regional interpretations inaccurate or suspect when based on the literature. In this study, the stratigraphic al nomenclature proposed by the Colombian Stratigraphical Lexicon (Porta, 1974) is followed.

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19 / n y\ ^ Tectonostratigraphic provinces 1. Atrato 2. Cauca 3. Lower Magdalena Valley 4. Cesar 5. Middle Magdalena Valley 6. Upper Magdalena Valley 7. Eastern Cordillera 8. Catatumbo 9. Llanos Foothills 10. LlanosAmazon 1 1. Non-sedimentary rocks 11 Figure 4-1. Sedimentary tectono-stratigraphic provinces of Colombia. The sections studied are in terranes 5, 8, and 9 indicated by dotted pattern (After Etayo-Serna, 1983).

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CHAPTER 5 BIOSTRATIGRAPHY Biostratigraphy is a very important for understanding Colombian geology because rocks are rarely well exposed, and structural geology is very complex due to the interaction of the Caribbean, South America and Nazca plates during the last 150 million years. Rapid and dramatic facies and thickness changes across faults are frequent, and correlation of formations requires an excellent biostratigraphic control. The most important, and very often the only, biostratigraphic tools in Tertiary sediments in the majority of Colombia are palynomorphs (mainly pollen and spores). Intense palynological work, mostly related to oil and coal exploration, has been done for the past 35 years. Unfortunately, not much work has been published especially for Paleogene sediments. One of the fundamental elements for producing a detailed biostratigraphic framework is a comprehensive understanding of pollen and spores taxonomy. A large percentage (-50%) of morphotypes described for Paleogene of Northern South America (see Table 5-1) lack detailed descriptions and good photographic records. In order to solve this problem, I visited the most important palynological collections of neotropical fossil pollen and spores that are available and still store some Paleogene holotypes (Petrobras in Rio de Janeiro, Pedevesa in Caracas, and University of Amsterdam in Amsterdam). Other collections, such as the one containing the 45 holotypes of Gonzalez (1967), were damaged and no longer useful (E. Gonzalez, personal communication). Others could not be found and possibly are already spoiled (most of Van der Hammen's holotypes of his 1955 to 1966 papers), and others are not available to the public or are not curated (Sarmiento, 1992). 20

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21 In the Appendix A I present a detailed taxonomic analysis of 300 pollen, spores, and dinoflagellate species, that will be used in the biostratigraphic analysis. Biostratigraphic ranges were analyzed using graphic correlation (see Chapter 3 for a more detailed description of this method). This approach is especially useful with pollen and spores because it allows an objective analysis of taxon range distributions. Phytogeography, especially in tropical regions where many species tend to have restricted ranges, would affect the use of traditional biostratigraphic zones. For example, there is a zone named Spinizonocolpites baculatus, defined by Muller et al. (1987) for the lower Paleocene of northern South America. The base of this zone is defined by the first occurrence of S. baculatus and the top by the last occurrence of S. baculatus. However, S. baculatus has long been recognized as related to Nypa, an extant mangrove palm living in South East Asia (Germeraad et al., 1968); therefore, S. baculatus would be restricted to lower coastal plain and estuarine facies. Fluvial sediments accumulated during the lower Paleocene would be unlikely to contain S. baculatus. Therefore, following the biostratigraphic zone approach, lower Paleocene strata would be "lacking" in fluvial sections because the pollen zone is absent, and an unconformity would be postulated. Probably, many of the "unconformities" that have been registered in Colombia strata (e.g., see Dengo and Covey, 1993) are an artifact of plant biogeography rather than time gaps. Graphic correlation approach accounts for facies changes and does not assume a priori that a particular taxon is a marker for any time interval. It also allows to use whole assemblages rather than "index" taxa and test hypothesis on range distributions. Graphic correlation becomes more robust as more information of different sections is added into the analysis. Finally, graphic correlation is more objective and relies less on personal opinion as traditional biostratigraphic zonations do.

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22 Previous Studies As far as can be determined thirty-three papers have been published on the Paleogene palynology of northern South America including Colombia, Venezuela, Guyana, and Brazil (Van der Hammen, 1954; Kuyl etal, 1955; Norem, 1955; Van der Hammen, 1956, 1957a,b, 1958; Garcia, 1958; Paba-Silva and Van der Hammen, 1958; Sole de Porta, 1961a,b, 1963: Porta and Sole de Porta, 1962; Van der Hammen and Wymstra, 1964; Leidelmeyer, 1966; Van der Hammen and Garcia, 1966; Gonzalez, 1967; Germeraad et al, 1968; Schuler and Doubinger, 1970; Sole de Porta, 1971; Wijmstra, 1971; Doubinger, 1973; Regali etal, 1974; Doubinger, 1976; Duenas, 1980; Muller etal, 1987; Colmenares, 1988; Colmenares and Teran, 1990, 1993; Sarmiento, 1992; Guerrero and Sarmiento, 1996; Rull, 1997b, 1998) All these papers, the majority of which were published before 1971, focused only on pollen and spores. Seventeen of them presented pollen/spores of Paleocene strata, five studies looked at Eocene strata, and five Oligocene strata. Only three of these studies provided measured stratigraphic sections with palynomorph range distributions. The publications listed above have yielded 339 taxa identified from Paleogene strata of northern South America including Brazil, Guiana, Venezuela, Peru, Ecuador and Colombia (Table 5-1). A comparison with living taxa have been attempted for just 55 of them. This information is summarized in Table 5-2, and Figure 5-1. Several zonation schemes based on pollen and spores have been proposed for the Paleocene-Eocene of northern South America (Van der Hammen, 1957a, b; Leidelmeyer, 1966; Gonzalez, 1967; Germeraad etal, 1968; Regali etal, 1974; Muller et al, 1987). However, only two (Germeraad et al, 1968; Regali et al, 197 '4) offered some independent justification for the proposed age assignments. Van der Hammen (1957 a, b; 1958) and his Holland school (Leidelmeyer, 1966; Gonzalez, 1967) were the precursors of palynological studies of Tertiary strata in northern South America. They used pollen/spores fluctuations (a pollen diagram) as a

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23

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24 Table 5-1. Pollen and spores named from the Paleogene of northern South America tax a Anacolosidites luteoides Annutriporites iversenni Arcotriporites asteroides Baculamonocolpites multispinosus Bacumorphomonocolpites tausae Bacustephanocolpites stereos Bombacacidites annae Bombacacidites brevis Bombacacidites ciriloensis Bombacacidites foveoreticulatus Bombacacidites soleformis Brevitricolpites variabilis Buttinia andreevi Cicatricosisporites baculatus Cicatricosisporites cirae Cicatricosisporites colombiensis Cicatricosisporites cristatus Cicatricosisporites cundinamarcensis Cicatricosisporites dorogensis Cicatricosisporites radiants Cicatricosisporites tabacensis Clamonocolpites terrificus Classites capucinii Clavainaperturites cordatus Clavamonocolpites microclavatus Clavastephanoporites ambigens Clavatricolpites gracilis Clavatricolporites leticiae Clavatriletes disparilis Colombipollis tropicalis Crassiectoapertites columbianus Crassitricolporites brasiliensis Crassitricolporites costatus Cricotriporites fragilis Cricotriporites guianensis Cricotriporites operculars Cristatricolpites analemae Crototricolpites americanus Crototricolpites annemarie Crusafontites grandiosus Cteniliphonidites costatus Ctenolophonidites lisamae Curvimonocolpites inornatus Cyclusphaera euribei Divisisporites enormus Duplotriporites ariani Echimonocolpites coni Echimonocolpites densus Echimonocolpites protofranciscoi Echimonocopites ruedae Echimorphomonocolpites gracilis Echimorphomonocolpites solitarius Echinatisporis minutis Echinoidites problematicus Echiperiporites akanthos Echiperiporites estelae Author Cookson and Pike, 1954 (Van der Hammen, 1954) Gonzalez, 1967 Gonzalez, 1967 (Van der Hammen, 1954) Sole de Porta, 1971 Sole de Porta, 1971 Gonzalez, 1967 (Van der Hammen, 1 954) Germeraad et al. , 1968 (Duenas, 1980) Muller etal. , 1987 Muller era/ ., 1987 Muller et al ., 1987 Muller et al ., 1987 Gonzalez, 1967 Boltenhagen, 1967 Regali, Uesugui, and Santos, 1974 Kedves and Sole de Porta, 1 963 Kedves and Sole de Porta, 1963 Regali, Uesugui, and Santos, 1974 Kedves and Sole de Porta, 1 963 (Potonie and Gelletich, 1933) Kedves, 1961 Krutzsch, 1959 Kedves and Sole de Porta, 1963 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Muller et al ., 1987 Leidelmeyer, 1966 Gonzalez, 1967 Leidelmeyer, 1966 Regali, Uesugui, and Santos, 1974 Sarmiento, 1992 Duenas, 1980 Herngreen, 1972 Sarmiento, 1992 Van Hoeken-Klinkenberg, 1966 Leidelmeyer, 1966 Van Hoeken-Klinkenberg, 1 966 Leidelmeyer, 1966 Wijmstra, 1971 Leidelmeyer, 1966 Sole de Porta, 1971 (Van Hoeken-Klinkenberg, 1964) Van Hoeken-Klinkenberg, 1966 (Van der Hammen and Garcia, 1966) Germeraad et al. , 1968 Leidelmeyer, 1966 Elsik, 1966 Pfug, 1953 Sarmiento, 1992 Sarmiento, 1992 Gonzalez, 1967 Sarmiento, 1992 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Gonzalez, 1967 Gonzalez, 1967 Van der Kaars, 1983 Gonzalez, 1967 Van der Hammen and Wymstra, 1964 Germeraad, Hopping, and Muller, 1968

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25 Table 5-1 --continued. tax a Echistephanoporites alfonsi Echitricolpites communis Echitricolpites polaris Echitriletes muelleri Echitriporites guianensis Echitriporites nuriae Echitriporites trianguliformis Ephedripites multicostatum Ephedripites vanegensis Ericipites annulatus Filtotriletes nigeriensis Foveodiporites guianensis Foveodiporites operculatus Foveostephanocolpites perfectus Foveostephanocolpites typicus Foveostephanocolporites liracostatus Foveotricolpites genuinus Foveotricolpites perforatus Foveotricolpites pomarius Foveotricolpites santanderianus Foveotricolporites caldensis Foveotricolporites crasiexinus Foveotricolporites marginatus Foveotricolporites voluminosus Foveotriletes margaritae Foveotriporites hammenii Gemmamonocolpites amicus Cemmamonocolpites barbatus Gemmamonocolpites dispersus Gemmamonocolpites gemmatus Gemmamonocolpites macrogemmatus Gemmamonocolpites ovatus Gemmastephanocolpites asteroformis Gemmastephanocolpites gemmatus Gemmastephanoporites breviculus Gemmastephanoporites polymorphus Gemmatricolpites pulcher Gemmatricolpites vigdisae Gemmatricolporites berbicensis Gemmatricolporites divaricatus Hamulatisporites caperatus Heterocolpites paleocenica Heterocolpites paluster Inaperturopollenites cursis Incertiscabrites pachoni Incerturugulites carbonensis Jandufouria seamrogiformis Janmulleripollis pentaradiatus Jussitriporites undulatus Laevigatosporites catanejensis Leiotriletes guadensis Longapertites brasiliensis Longapertites circularis Longapertites fossuloides Longapertites perforatus Longapertites perforatus author Leidelmeyer, 1966 Regali, Uesugui, and Santos, 1974 Regali, Uesugui, and Santos, 1974 Regali, Uesugui, and Santos, 1974 Leidelmeyer, 1966 Duenas, 1980 Van Hoeken-Klinkenberg, 1964 Brenner, 1963 Van der Hammen and Garcia, 1966 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Wijmstra, 1971 Van der Kaars, 1983 Leidelmeyer, 1966 Leidelmeyer, 1966 Leidelmeyer, 1966 Gonzalez, 1967 Van der Hammen and Garcia, 1966 Van der Hammen and Garcia, 1966 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Gonzalez, 1967 Gonzalez, 1967 (Van der Hammen, 1954) Germeraad, Hopping, and Muller, 1968 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Sarmiento, 1992 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Muller, Giacomo, and Erve, 1987 Gonzalez, 1967 Leidelmeyer, 1966 Van der Hammen and Garcia, 1966 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer, 1966 Leidelmeyer, 1966 Leidelmeyer, 1966 (Van Hoeken-Klinkenberg 1964) Schrank, 1994 Van der Hammen and Garcia, 1966 Gonzalez, 1967 Sarmiento, 1992 (Van der Hammen, 1954) Sarmiento, 1992 Sarmiento, 1992 Germeraad, Hopping, and Muller, 1968 Di Giacomo and Van Erve, 1987 Gonzalez, 1967 Muller, Giacomo, and Erve, 1987 (Van Der Hammen, 1954) Sole de Porta, 1971 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Sarmiento, 1992

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Table 5-1 —continued. tax a L proxapertitoides var proxapertitoides L proxapertitoides var reticulatus L proxapertitoides var. reticuloides Longapertites vaneendenburgi Longitrichotomocolpites triangularis Magnaperiporites spinosus Magnastriatites grandiosus Magnatriporites abstractus Magnotetradites magnus Margocolporites vanwijhei Mauritiidites franciscoi var. franciscoi Mauritiidites franciscoi var. minutus M. franciscoi var. pahyexinatus Microfoveolatosporis skottsbergii M icrofo veotriporites cretaceous Momipites africanus Monolites ferdinandi Monoporites annulatus Monoporites annuloides Monoporites parens Papillamonocolpites splendedus Papillopolis partialis Perfotricolpites digitatus Perfotricotpites semistriatus Periretipollis spinosus Periretisyncolpites giganteus Perisyncolporites pokornyi Plicapollis arcii Polotricolporites concretus Polotricolporites mocinnii Polotricolporites versabilis Polyadopollenites mariae Polypodiaceoisporites potonie Proteacidites dehaani Proteacidites miniporatus Protudiporites typicus Proxapertites cursus Proxapertites facet us Proxapertites humbertoides Proxapertites magnus Proxapertites minutus Proxapertites operculatus Proxapertites psilatus Proxapertites tertiaria Proxapertites verrucatus Pseudostephanocolpites perfectus Pseudostephanocolpites ? verdi Psilabrevitricolpites flexibilis Psilabre vitricolpites rotundus Psilabrevitricolporites annulatus Psilabrevitricolporites simpliformis Psiladiporites redundantis Psilamonocolpites ciscudae Psilamonocolpites grandis Psilamonocolpites huertasi Psilamonocolpites medius 26 author Van der Hammen and Garcia, 1966 Van der Hammen and Garcia, 1966 Gonzalez, 1967 Germeraad, Hopping, and Muller, 1968 Gonzalez, 1967 Gonzalez, 1967 (Kedves and Sole de Porta, 1963) Duenas 1980 Gonzalez, 1967 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Germeraad, Hopping, and Muller, 1968 (Van der Hammen, 1956) Van Hoeken-Klinkenberg, 1964 Van der Hammen and Garcia, 1966 Van der Hammen and Garcia, 1966 (Selling, 1946) Srivastava, 1971 Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 (Van der Hammen, 1954) Sole de Porta, 1972 Van der Hammen, 1954 Gonzalez, 1967 Sarmiento, 1992 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Legoux, Belsky, and Jardine, 1972 Keiser and Du Chene, 1979 Germeraad, Hopping, and Muller, 1968 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Duenas, 1980 (Potonie and Gell, 1933) Kedves, 1961 Germeraad, Hopping, and Muller, 1968 Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 Regali, Uesugui, and Santos, 1974 (Van der Hammen, 1954) Sarmiento, 1992 Muller, Giacomo, and Erve, 1987 Duenas, 1980 (Van der Hammen, 1954) Van der Hammen, 1956 Sarmiento, 1992 Van der Hammen and Garcia, 1966 Sarmiento, 1992 Gonzalez, 1967 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 Sarmiento, 1992 Van der Kaars, 1983 Gonzalez, 1967 Sarmiento, 1992 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966

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27 Table 5-1 -continued. tax a Psilastephanocolpites adinos Psilastephanocolpites globulus Psilastephanocolpiles maia Psilastephanocolpites marginatus Psilastephanocolpites verrucosus Psilastephanocolporites fissilis Psilastephanocolporites globulus Psilastephanocolporites variabilis Psilastephanoporites caribiensis Psilastephanoporites stellatus Psilasyncolporites parvus Psilatephanocolpites regularis Psilatricolpites acerbus Psilatricolpites brevis Psilatricolpites clarissimus Psilatricolpites colpiconstrictus Psilatricolpites microverrucatus Psilatricolpites minutus Psilatricolpites operculatus var. minutus Psilatricolpites palaeoceanica Psilatricolpites polaroides Psilatricolpites simplex Psilatricolpites solus Psilatricolpites undamarginis Psilatricolporites costatus Psilatricolporites crassus Psilatricolporites maculosus Psilatricolporites marginatus Psilatricolporites normalis Psilatricolporites obscurus Psilatricolporites operculatus P. operculatus var. medius Psilatricolporites optimus Psilatricolporites pachyexinatus Psilatricolporites transversalis Psilatricolporites triangularis Psilatricolporites vanus Psilatriletes martinensis Racemonocolpites facilis Racemonocolpites racematus Racemonocolpites racematus Racemonocolpites romanus Retibrevitricolpites catatumbus Retibrevitricolpites distinctus Retibrevitricolpites increatus Retibrevitricolpites retibolus Retibrevitricolpites triangulatus Retidiporites agilis Retidiporites botulus Retidiporites elongatus Retidiporites magdalenensis Retiheterocolpites tertiarus Retimonocolpites bernardii Retimonocolpites claris Retimonocolpites longapertitoides Retimonocolpites microreticulatus author Gonzalez, 1967 Van der Kaars, 1983 Leidelmeyer, 1966 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer, 1966 Van Hoeken-Klinkenberg, 1966 Regali, Uesugui, and Santos, 1974 Duenas, 1980 Regali, Uesugui, and Santos, 1974 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1 966 Gonzalez, 1967 Gonzalez, 1967 Van der Hammen and Wymstra, 1964 Van Hoeken-Klinkenberg, 1966 Sarmiento, 1992 Gonzalez, 1967 Gonzalez, 1967 Van der Hammen and Garcia, 1966 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer, 1966 Leidelmeyer, 1966 Duenas, 1980 Van der Hammen and Wymstra, 1964 Regali, Uesugui, and Santos, 1974 Van der Kaars, 1983 Gonzalez, 1967 Gonzalez, 1967 Van der Hammen and Wymstra, 1964 Gonzalez, 1967 Gonzalez, 1967 Van der Kaars, 1983 Duenas, 1980 Van der Hammen and Wymstra, 1964 Gonzalez, 1967 Sarmiento, 1992 Gonzalez, 1967 (Van der Hammen, 1954) Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1 966 Gonzalez, 1967 Leidelmeyer, 1966 Van Hoeken-Klinkenberg, 1966 Gonzalez, 1967 Leidelmeyer, 1966 Sarmiento, 1992 Van der Hammen and Garcia, 1966 Gonzalez, 1967 Gonzalez, 1967 Sarmiento, 1992 Sarmiento, 1992 Van der Hammen and Garcia, 1966

PAGE 38

28 Table 5-1 —continued. taxa Relimonocolpites splendidus Retimonocolpites tertiarius Relipollenites confusus Retislephanocolpites angeli Retistephanocolpites fmalis Retislephanocolpites minutus Retistephanocolpites regularis Retistephanocolpites tropicalis Retistephanocolpites williamsi Retistephanocolporites festivus Retistephanoporites angelicus Retisyncolporites angularis Retisyncolporites aureus Retitricolpites absolutus Retitricolpites adeptus Retitricolpites adultus Retitricolpites agricaulis Retitricolpites amapaensis Retitricolpites antonii Retitricolpites bonus Retitricolpites brevicolpatus Retitricolpites cecryphalium Retitricolpites clarensis Retitricolpites colombiae Retitricolpites concilialus Retitricolpites constrictus Retitricolpites florentinus Retitricolpites herrerae Retitricolpites incisus Retitricolpites josephinae Retitricolpites kwakwanensis Retitricolpites magnus Retitricolpites malediclus Retitricolpites marginatus Retitricolpites maturus Retitricolpites microreticulatus Retitricolpites minutus Retitricolpites minutus Retitricolpites obtusus Retitricolpites ovalis Retitricolpites perditus Retitricolpites perforatus Retitricolpites retiaphelis Retitricolpites reticulatus Retitricolpites saturum Retitricolpites simplex Retitricolporites amazonensis Retitricolporites cienaguensis Retitricolporites costatus Retitricolporites craceus Retitricolporites crassicostatus Retitricolporites crassicostatus Retitricolporites ellipticus Retitricolporites equatoriales Retitricolporites exinamplius Retitricolporites finitus author Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer, 1966 Gonzalez, 1967 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Duenas, 1980 Germeraad, Hopping, and Muller, 1968 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer, 1966 Regali, Uesugui, and Santos, 1974 Gonzalez, 1967 Gonzalez, 1967 Sarmiento, 1992 Leidelmeyer, 1966 Gonzalez, 1967 (Van der Hammen, 1954) Sarmiento, 1992 Gonzalez, 1967 Gonzalez, 1967 Gonzalez, 1967 (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Gonzalez, 1967 (Van der Hammen, 1954) Sarmiento, 1992 Leidelmeyer, 1966 Gonzalez, 1967 Gonzalez, 1967 Van Hoeken-Klinkenberg, 1966 Gonzalez, 1967 (Van der Hammen, 1954) Van der Hammen and Wymstra, 1964 Gonzalez, 1967 Pierce, 1961 Van Hoeken-Klinkenberg, 1966 Van der Hammen and Wymstra, 1964 Gonzalez, 1967 Gonzalez, 1967 Leidelmeyer. 1966 (Van der Hammen, 1954) Van der Hammen and Wymstra, 1964 Gonzalez, 1967 Gonzalez, 1967 Regali, Uesugui, and Santos, 1974 Duenas, 1980 Leidelmeyer, 1966 Gonzalez, 1967 Van der Hammen and Wymstra, 1964 Van Hoeken-Klinkenberg, 1966 Van Hoeken-Klinkenberg, 1966 Gonzalez, 1967 Sarmiento, 1992 Gonzalez, 1967

PAGE 39

29 Table 5-1 --continued. tax a author Retitricolporites irregularis Van der Hammen and Wymstra, 1964 Retitricolporites marianis Gonzalez, 1967 Retitricolporites mariposus Leidelmeyer, 1966 Retitricolporites medius Gonzalez, 1967 Retitricolporites perpusillus Regali, Uesugui, and Santos, 1974 Retitricolporites profundus Gonzalez, 1967 Retitricolporites quadrosis Regali, Uesugui, and Santos, 1974 Retitricolporites saskiae Gonzalez, 1967 Retitricolporites squarrosus Van der Hammen and Wymstra, 1964 Retitriporites dubiosus Gonzalez, 1967 Retitriporites federicii Gonzalez, 1967 Retitriporites simplex Van der Kaars, 1983 Retitriporites tilburgii Gonzalez, 1967 Retitriporites typicus Gonzalez, 1967 Rugotricolpites oblatus Sarmiento, 1992 Rugotricolporites felix Gonzalez, 1967 Scabraperiporites asymmetricus Duenas, 1980 Scabraperiporites nativensis Regali, Uesugui, and Santos, 1974 Scabrastephanocolpites guaduensis (Van der Hammen, 1954) Sarmiento, 1992 Scabrastephanocolpites scabratus Van der Hammen and Garcia, 1966 Scabrastephanocolpites vanegensis Van der Hammen and Garcia, 1966 Scabratricolpites angelicus Sarmiento, 1992 Scabratricolpites thomasi Sarmiento, 1992 Scabratricolpites tibialis Gonzalez, 1967 Scabratricolporites platanensis Duenas, 1980 Scabratriletes globulatus Sarmiento, 1992 Scabratriporites moderatus Gonzalez, 1967 Scabratriporites redundans Gonzalez, 1967 Scabratriporites simpliformis Van Hoeken-Klinkenberg, 1966 Semitectotriporites gratus Gonzalez, 1967 Spinozonocolpites baculatus Muller, 1968 Spinozonocolpites echinatus Muller, 1968 Spinozonocolpites intrarugulatus Muller, Giacomo, and Erve, 1987 Spinozonocolpites sutae Sarmiento, 1992 Spironsyncolpites spiralis Gonzalez, 1967 Spirosyncolpites clavatus Gonzalez, 1967 Stephanocolpites costatus Van der Hammen, 1954 Striatricolpites catatumbus Gonzalez, 1967 Striatricolpites minor Wijmstra, 1971 Striatricolpites semistriatus Gonzalez, 1967 Striatricolporites agustinus Gonzalez, 1967 Striatricolporites meleneae Duenas, 1980 Striatricolporites pimulis Leidelmeyer, 1966 Striatricolporites tenuissimus Duenas, 1980 Striatriporites nigeriensis Van Hoeken-Klinkenberg, 1966 Syncolporites lisamae Van der Hammen, 1954 Syncolporites marginatus Van Hoeken-Klinkenberg, 1964 Syncolporites poricostatus Van Hoeken-Klinkenberg, 1966 Syncolporites rugucostatus Sarmiento, 1992 Syndemicolpites tipicus Van Hoeken-Klinkenberg, 1964 Tetradites umirensis Van der Hammen, 1954 Tricolpites rubini Van der Hammen, 1954 Ulmoideipites krempii (Anderson, 1960) Elsik, 1968b Venezuelites globoannulatus Muller, Giacomo, and Erve, 1987 Verrucatosporites usmensis (Van der Hammen, 1956) Germeraad etal. , 1968 Verrustephanocolpites verrucatus Van der Hammen and Garcia, 1966

PAGE 40

30 Table 5-1— continued. taxa Verrutricolpites isolatus Verrutricolpites unicus Verrutricolpites verrubolus Verrutricolporites haplites Verrutricolporites rotundiporis Verrutriporites asymmetricus Wilsonipites margocolpatus Zlivisporis blanensis Zonocostites duquensis Zonocostites ramonae Zonotricolpites lineaus Zonotricolpites variabilis author Leidelmeyer, 1966 Gonzalez, 1967 Leidelmeyer, 1966 Gonzalez, 1967 Van der Hammen and Wymstra, 1964 Regali, Uesugui, and Santos, 1974 Muller, Giacomo, and Erve, 1987 Pacltova, 1961 Duenas, 1980 Germeraad, Hopping, and Muller, 1968 Sarmiento, 1992 Sarmiento, 1992

PAGE 41

31 Table 5-2. Botanical affinities for fossil sporomorphs from northern South America (After Van der Hammen 1954, 1956, 1957a,b; Sole de Porta, 1961a, b; Van der Hammen and Garcia, 1966; Gonzalez, 1967; Germeraad et al ., 1968; Mullere/a/. , 1987; Sarmiento, 1992). Dispersion centers after Gentry (1982), suprageneric classification after Judd et al . (1999) FOSSIL SPOROMORPH PROBABLE BOTANICAL AFFINITY FAMILY FAMILY DISPERSION CENTER* Alnipollenites verus Alnus Betulaceae L Anacolosidites luteoides Anacolosa Cathedra Ptychopetalum Olacaceae AZ Bombacacidites annae Bombax ceiba B. rhodognaphalon B. pubescens Bombacaceae AZ Buttinia andreevi Unknown Cicatricosisporites dorogensis Anemia hlohria Schizaeaceae Crassoretitriletes vanraadshooveni Lygodium microphyllum Schizaeaceae Ctenolophonidites costatus Ctenolophon engleri Ctenolophonaceae Ctenolophonidites lisamae Ctenolophon Ctenolophonaceae Echiperiporites estelae Thespesia populnea Hibiscus tiliaceus Hibiscus rosa-sinensis lpomoea phillomega Malvaceae Convolvulaceae AZ Echitricolporites minutus Ambrosia Crassocephalum ha Xanthium Compositae AN Echitricolporites spinosus Espeletia Mikania Pedis Wedelia Wulfta Compositae AN Echitriporites trianguliformis Embothrium Gamieria Persoonia Telopea Proteaceae SA Florschuetzia trilobata F. levipoli F. semilobata Lagerstroemia flos-regina Sonneratia alba Lythraceae Fenestrites spinosus Elephantopus angustifolia Rolandia fruticosa Vernonia canescens Vemonia remotiflora Compositae AN Foveotricolpites perforates Extinct Foveotriletes margaritae Lindsaya orbiculata Ophioglossum falcatum 0. concinnuum

PAGE 42

32 Table 5-2— continued. rUoolL orUKUMUKrn — — PROBABLE BOTANICAL ArrlNll Y FAMILY FAMILY DISPERSION CENTER* Grimsdalea magnaclavata Palm type Palmae AZ Heterocolpites paluster Melastomataceae AN Jandufouria seamrogiformis Catostemma Malvaceae AZ Jussitriporites undulatus Onagraceae SA Longapertites perforatus Annonaceae AZ Longapertites brasiliensis Annonaceae AZ Magnastriatites grandiosus Leratopteris (fresh-water) Parkeriaceae Magnaperiporites spinosus Mirabilis Nyctaginaceae Margocolporites vanwijhei Caesalpinia Adipera Brasilettia Haematoxylon Mezoneuron Poincianella Fabaceae Mauritiidites franciscoi Mauritia Palmae AZ Monoporites anulatus Poaceae ? Multiareolites formosus Adhatoda Anisotus Baloperone Dianthera Jacobinia Justicia Kolobochilus Monechma Rungia Acanthaceae AN Multimarginites vanderhammeni Sanchezia klugii Trichanthera gigantea Acanthaceae AN Pachydermites diederixi Svmphonia globulifera Guttiferae AN Perfotricolpites digitatus Merremia glabra M. umbellata Convolvulaceae AZ Scaevola Goodeniaceae ? Valerianella stenocarpa Caprifoliacea i Perisyncolporites pokomyi Brachypteris Bunchosia Hiraea grandifolia Mascagnia Stigmaphyllum Tetrapterys Malpighiaceae A7 Proteacidites dehaani Guevina avellana Proteaceae SA Proxapertites cursus Nypa related Proxapertites operculars Nypa related Astrocarium (sensu TVH) Palmae AZ Psiladiporites minimus Artocarpus Ficus Sorocea Moraceae AZ

PAGE 43

33 Table 5-2— continued. FOSSIL SPOROMORPH PROBABLE BOTANICAL AFFINITY FAMILY FAMILY DISPERSION CENTER* Retibrevitricolpites triangulatus Extinct Retidiporites magdalenensis Banksia collina Dryandra longifolia Proteaceae SA Retistephanocolpites williamsi Ctenolophon parfivolius Ctenolophonaceae Retisyncolporites angularis Can oca r Caryocaraceae Retitricolporites irregularis Amanoa oblongifolia Pseudolachnostylis glauca Euphorbiaceae AZ Retitricolporites saskiae Retricolporites guianensis 9 Firmiania colorata Hildegardia barteri Glossostemon bruguieri Pterocymbium beccari Sterculia mexicana Trichospermum Malvaceae Malvaceae AZ Spinozonocolpites baculatus Spinozonocolpites echinatus Nypa fruticans Palmae AZ Stephanocolpites costatus Tabernaemontana attenuata Apocynaceae AZ Striansyncolpites zwaardi Cuphea Lythraceae L? Striatricolpites catatumbus Crudia Anthonotha Isoberlinia Macrolobium bifdium Fabaceae sub. Faboideae L Striatricolporites agustinus Anacardiaceae AZ? Syncolporites lisamae Myrtaceae Verrucatosporites usmensis Stenochlaena palustris Phlebodium aureum Histiosperis incisa Polypodium pectinatum P. triseriale Polypodiaceae Verrutricolporites rotundiporis Crenea maritima Lythraceae AZ Zonocostites ramonae Rhizophora Bruguiera Ceriops Carallia Rhizophoraceae AZ AZ: Amazon AN: Andes SA: Southern South America L: Laurasia

PAGE 44

34 proxy for climatic cycles that presumably have a chronostratigraphic value. This "pollen diagram" is based on coal samples from different areas in Colombia. Proportions of different elements such as Psilamonocolpites group, Mauritiidites group, Psilatriletes group, are then calculated and plotted along the stratigraphic sections. Abundance peaks of specific groups are assumed to represent vegetational changes due to regional climatic changes. Therefore, they assumed that these peaks have a chronostratigraphic value and can be used for correlation. The epochs and ages of the Tertiary are then positioned in the pollen diagram based on the changes of relative proportions of certain groups, assuming that climatic changes are correlated with epoch/age boundaries. Van der Hammen (1958) correlates the base of each epoch to an arenite level. This biostratigraphic scheme is then used to date most of the Tertiary continental formations of Colombia and Guyana (Van der Hammen, 1957a, 1957b, 1958; Van der Hammen and Wymstra, 1964; Leidelmeyer, 1966; Gonzalez, 1967; Wijmstra, 1971). Many of those datings are still deeply rooted in Colombian stratigraphy and used for correlation and modeling purposes. However, there are many problems associated with this approach. First, there is a statistical artifact associated with Van der Hammen's pollen diagrams, which is called the "closed sum" (Moore etal, 1991; Kovach and Batten, 1994). Percentages of each sporomorph group were calculated by counting 200300 grains per sample, then, the results were normalized. This method, however, tends to produce artificial negative correlations, when a group (A) significantly increases its abundance in a sample, another group (B) automatically decreases its abundances, even though its real abundance did not change. Then, these negative correlations among Van der Hammen groups could be an artifact of normalization, and peaks of certain groups could be the product of a decrease in other groups. There is also the weak assumption that pollen production and dispersal is similar for all species and that all taxa have a regional distribution (Porta and Sole de Porta, 1962). Furthermore, coals, the main source of Van der Hammen's samples, generally have a unique and facies-restricted flora

PAGE 45

35 that is unsuitable for biostratigraphic purposes (Traverse, 1988). Porta and Sole de Porta (1962) analyzed twenty-four samples in 12 stratigraphic meters of a Miocene section in Cundinamarca, and found that its pollen diagram could be easily correlated with zones A and B of a general pollen diagram for the Oligocene. This approach also does not use an independent data-set that can test the ages given by pollen groups, therefore circular reasoning is highly possible. In conclusion, correlation of "climatic cycles" deduced from the pollen record probably reflects similar ecological conditions rather than time lines, and should not be used as a tool for dating Tertiary rocks. Germeraad etal. (1968) in a pioneer study proposed a number of palynological zones for tropical Tertiary sediments. The zones were based mainly on material from Nigeria, Venezuela, and Colombia. They used several planktonic foraminifera to correlate their palynological zones to the geologic time scale. The stratigraphic ranges of those foraminifera taxa are presented in Figure 5-2. Ranges are derived from Postuma (1971), Bolli and Saunders (1985), Tourmankine and Luterbache (1985) (T&L85), Bolli etal. (1994), and Robinson and Wright (1993). Taxa that are not in Figure 5-2, but were mentioned by Germeraad et al. (1968), correspond to those of local importance that are not commonly used for global correlation. The following are the palynological zones proposed by Germeraad and the foraminifera used to correlate them with the geologic time scale (unless actually cited, the publications in which the names first appeared are not listed in the References list). The list also include the geographic location where the foraminifera were recorded from: 1. Retidiporites magdalenensis zone Danian-Paleocene Nigeria lower part of zone: Danian Globigerina compressa (now Planorotalites compressa (Plummer 1926) Tourmankine, and Luterbache 1985): upper P lb-top P3 (T&L85)

PAGE 46

36 Danian Paleocene Ages and zones _ . _ . Retidipontes by Germeraad , , etal 1968 magdalenensis zone lower upper Paleocene Early Eocene Retibrevilricolpites triangulatus zone lower upper late Early Eocene -Middle Eocene Monoporiles annulalus zone 1 M) on c3 «> ill J S*s CD CD > a a e V I I o Si 9 Si I -s 3 5 aO «». as as as as as as as Q (J -a, S J3 S 5 | k. -O ? 2 5 2 2 I 9 i 5 .£ •a; s; a iu <°f s late Middle Eocene -Late Eocene Verrucatosporites usmensis zone Olig. -a B I i -a -Z 2 5. 1 3 I a a ! a =3 P17 >16 — P15 f>14 '13 i>12 Pll P10 P9 re P7 P6 R3 P2 J 1 I I a a a C -a a t Fi gure 5-2. Chronostratigraphic ranges of foraminifera used to calibrate Germeraad et al. (1968) palynological zonation

PAGE 47

37 G. daubjergensis (now Globoconusa daubjergensis (Bronnimann 1953) Toumarkine and Luterbacher 1985) middle Pla-top Pld (T&L85) Nigeria upper part of zone: Paleocene Globorotalia pseudomenardii (now Planorotalites pseudomenardii (Bolli 1957) Toumarkine and Luterbacher 1985) base P4-top P4 (T&L85) G. velascoensis (now Morozovella velascoensis (Cushman 1925) Toumarkine and Luterbacher 1985): base P4-lowest P6 (T&L85) G. acuta (now Morozovella acuta (Toulmin 1941) Toumarkine and Luterbacher 1985): upper P3-~middle P6 (T&L85) 2. Retibrevitricolpites triangulatus zone Paleocene-early Eocene Colombia lower part of zone: Paleocene Actinosiphon barbadensis Nigeria lower part of zone: Paleocene Globorotalia velascoensis (now Morozovella velascoensis (Cushman 1925) Toumarkine and Luterbacher 1985): base P4-lowest P6 (T&L85) G. acuta (now Morozovella acuta (Toulmin 1941) Toumarkine and Luterbacher 1985): upper P3-~middle P6 (T&L85) Nigeria upper part of zone: early Eocene Globorotalia formosa (now Morozovella formosa formosa (Bolli 1957) Toumarkine and Luterbacher 1985): upper P6-upper P8 (T&L85)

PAGE 48

38 Globorotalia rex Martin 1943: G.rex zone to lower part of G. formosa/aragonensis zone (Postuma, 1971). This is equivalent to P6 zone. 3. Monoporites annulatus zone late early Eocene-middle Eocene. This zone in the Caribbean is subdivided in the Psilatricolporites crassus, Psilatricolporites operculatus, and Retritricolporites guianensis zones. Nigeria lower, middle and upper part of zone: late early Eocene-middle Eocene Cassigerinelloita amekiensis Stolk 1963 3a. Psilatricolporites crassus zone middle Eocene Venezuela lower part of zone: early middle Eocene Linderina floridensis Helicostegina gyralis Barker and Grimsdale, 1936: middle P6b/P9-middle P10/12, in lower part of Chapelton Formation Jamaica (Robinson and Wright, 1993). Authors probably refer to zones of Berggren and Miller (1988) that established Paleocene/ Eocene boundary in P6a/b boundary (P6a defined by LAD of M. velascoensis). Lepidocyclina sp. A Venezuela upper part of zone: late middle Eocene Helicolepidina spiralis form C in Van Raadshoven (195 1). A larger foraminifera from Rio San Pedro fauna, Zulia, Venezuela. According to Van Raadshooven (1951), it occur in middle Eocene beds in Maracaibo area. Proposed age is based on co-occurrence with Pseudophragmina (Proporocyclina) cf. perpusilla (Vaughan), Ferayina coralliformis

PAGE 49

39 Frizzell, and Lepidocyclina aff. Lepidocyclina peruviana-r. douvillei group, that are also larger foraminifera. 3b. Psilatricolpites operculatus and Retitricolpites guianensis zone late middle Eocene Venezuela Helicolepidina spiralis Tobler. A larger foraminifera from Rio San Pedro fauna, Zulia, Venezuela. According to Van Raadshooven (1951), it occurs in middle Eocene beds in Maracaibo area. Proposed age is based on co-occurrence with Pseudophragmina (Proporocyclina) cf. perpusilla (Vaughan), Ferayina coralliformis Frizzell, and Lepidocyclina aff. Lepidocyclina peruviana-r. douvillei group, that are also larger foraminifera. 4. Verrucatosporites usmensis zone late middle to late Eocene Venezuela lower part of zone: late middle Eocene Helicolepidina spiralis Tobler. A larger foraminifera from Rio San Pedro fauna, Zulia, Venezuela. According to Van Raadshooven (1951), it occurs in middle Eocene beds in Maracaibo area. Proposed age is based on co-occurrence with Pseudophragmina {Proporocyclina) cf. perpusilla (Vaughan), Ferayina coralliformis Frizzell, and Lepidocyclina aff. Lepidocyclina peruviana-r. douvillei group, that are also larger foraminifera. Van Raadshooven (1951) also states that many species of larger foraminifera from Venezuela are new and difficult to correlated outside the Western Venezuelan basins. Venezuela upper part of zone: late Eocene

PAGE 50

40 Lepidocyclina pustulosa H. Douville, 1917: base P12-top P17 (Robinson and Wright, 1993) Pseudophragmina mirandana Hodson: a larger foraminifera from Rio San Pedro fauna, Zulia, Venezuela Nummulites striatoreticulatus Rutten 1928: middle P12/P14 top P17 (Robinson and Wright, 1993). Helicostegina soldadensis Grimsdale: a larger foraminifera from Venezuela Colombia upper part of the zone: late Eocene Bulimina jacksonensis Cushman 1925: late Eocene, in Globigerinatheka semiinvoluta and Turborotalia cerroazulenzis zones (Bolli et al, 1994), base PI 5top P17. Nigeria lower and upper part of zone: late middle Eocene-late Eocene ChUoguembelina martini Truncorotaloides rohri Bronnimann and Bermudez: middle P9-top P14 (T&L85). 5. Cicatricosisporites dorogensis zone Oligocene Caribbean Globigerina ampliaperturata middle P16 to P20, late late Eocene to early middle Oligocene (T&L85; Bolli and Saunders, 1985) G. ciperoensis ciperoensis P20 to middle P22, middle to early late Oligocene (Bolli and Saunders, 1985) Globorotalia opima opima P21, late middle Oligocene (Bolli and Saunders, 1985) G. kugleri Bolli 1957, P22-N4, late Oligocene to early Miocene (Bolli and Saunders, 1985)

PAGE 51

41 Nigeria G. ciperoensis ciperoensis P20 to middle P22, middle to early late Oligocene (Bolli and Saunders, 1985) G. ciperoensis angulisuturalis P21 to middle P22, late middle Oligocene to early late Oligocene (Bolli and Saunders, 1985) G. kugleri Bolli 1957, P22-N4, late Oligocene to early Miocene (Bolli and Saunders, 1985) In general, the age assignments of the Germeraad zones seems to be confirmed by the foraminifera (Fig. 5-2). However, the level of resolution is low compared to foraminiferal zones. The early and middle Eocene, and the Paleocene-Eocene boundary are very poorly resolved. Also, the lower boundary of the Verrucatosporites usmensis zone could be older than currently assumed (early? middle Eocene). The stratigraphic position of the foraminifera in relation with sporomorph ranges, however, was not presented in their paper with the exception of three sections in Nigeria. These three sections contain only planktonic zones P4 to P14 (Upper Paleocene to middle Eocene). It is difficult, then, to evaluate the calibration of the Germeraad zones especially for the middle and late Eocene. Regali et al. (1974) also established several palynological zones for the Paleocene-Eocene of Brazil. The age for each zone is given by correlation with a planktonic foraminifera zonation for Brazil. Unfortunately they did not state what foraminifera taxa were used to calibrate the zonation, precluding an analysis of their data. However, it is evident a disparity in age assignments when compared with Germeraad et al. (1968) zones. For example the range of Proxapertites cursus is considered early Eocene, while it is Paleocene in Germeraad et al. (1968) scheme. When Germeraad et al. (1968) and Regali et al. (1974) zonations are compared (Fig. 5-3), it is evident a large discrepancy in the chronostratigraphic significance of many taxa. An 84% of the taxa

PAGE 52

Figure 5-3. Comparison of Germeraad et al. (1968), Regali et al. (1974), and Muller et al. (1987) zonations. Name of taxa are in Table 5-6. Tibui section (Gonzalez, 1967) is compared against Muller's zonation suggesting a hiatus in the zonation. Circles=first appearance datums, Crosses=last appearance datums.

PAGE 53

43 compared have discrepancies in the assumed chronostratigraphic value of first (FAD) and last appearance (LAD) datums (e.g., LAD of Cicatricosisporites dorogensis (#42), Perisyncolporites pokornyi (#172), Perfotricolpites digitatus (#170), etc.). A zonations is supposed to represent the absolute stratigraphic ranges of all taxa included. Here, evidently either both zonations are local in extent and/or they do not have the true range of most of the taxa involved. Muller et al. (1987) established 1 1 palynological zones. Their work is mainly based on the Germeraad et al. (1968) zonation. Several modifications were done. The lower part of V. usmensis zone is considered middle Eocene, and the middle Eocene is subdivided into 6 zones. However, they did not provide independent data supporting the new age assignments as well as range charts of any of the sections analyzed. Colmenares and Teran (1993) and Sarmiento (1992) have challenged the regional application of these zones for western Venezuela, and central Colombia. Some of their zones could be ecological assemblages (Colmenares and Teran, 1993). A great discrepancy in biostratigraphic ranges and their chronostratigraphic significance is evident when comparing Muller with Germeraad and Regali's zonations (Fig. 5-3). Muller et al. (1987) and Germeraad et al. (1968) have a discrepancy of 47% in the range of the taxa compared (8 out of 17 taxa); while Muller vs. Regali have a discrepancy of 66% (12 out 18 taxa). Furthermore, the comparison of the sporomorph record of a section in the Catatumbo area (Gonzalez, 1967) with the Muller et al. (1974) zonation (Fig. 5-3) suggests a major hiatus in the zonation, casting serious doubts on the temporal and spatial significance of Muller zonation for the Eocene. In summary, there is weak support and low resolution for age assignments of the palynological zones that have been proposed for the Paleocene-Eocene of northern South America. Subdivisions of the Eocene, and the exact paleontological and stratigraphical position of the Paleocene-Eocene boundary are still elusive.

PAGE 54

44 Results Using the graphic correlation technique (Shaw, 1964; Edwards, 1984; Edwards, 1989), a Composite Section (CS) was developed based on the stratigraphic distribution of pollen, spores, and dinoflagellate cysts of the three sections studied (see range charts in Tables 5-3 to 5-5) and the only two additional sections available from literature with palynomorph range charts and samples referenced to a stratigraphic position in a measured section (Tibui section in Catatumbo area after Germeraad etal, 1968, and well Tl in Maracaibo Basin after Rull, 1997b). Eightyfour palynomorph taxa were selected to be used in the graphic correlation. This selection was based on common occurrence in all or most of the sections and a recognized chronostratigraphic potential based on experience of previous zonations (Germeraad etal, 1968, Regali et al, 1974, Muller et al, 1987). First and last appearance datums (FAD and LAD respectively) for the five sections are summarized in Table 5-6. Also, abundance peaks of selected taxa (e.g., Longapertites) were included to evaluate their potential as a chronostratigraphic correlation tools. For Tibui section, 0 meters was assumed to be at the base of section in the Figure 3 of Gonzalez (1967). Gonzalez (1967) datums for Cicatricosisporites dorogensis and Verrucatosporites usmensis group were excluded from the analysis because he did not provide photographs of the grains and serious doubts have been made on Gonzalez' correct identification of these two taxa (Germeraad et al, 1968). For Tl well (Rull, 1997b), 0 meters was considered at depth 2700 increasing upwell (Rull, 1997b, Fig. 3, p.82). Five rounds of correlation were performed on the five stratigraphic sections in order to produce a Composite Section (a detailed explanation of graphic correlation procedure is given in Chapter 3). The two first rounds of correlation are shown in Figures 5-4, 5-5, 5-6, 5-7, 5-8, 5-9, and 5-10. The processes were repeated until ranges of each taxon stabilized. The first and last appearance datums of the taxa in

PAGE 55

45 final Composite Section (CS) are shown in Table 5-7. Each of the sections was, then, correlated with the CS (Figs. 5-11 and 5-12). The Composite Section (CS) was also compared with two sections of the Germeraad et al. (1968) work that had palynological range charts but lacked an exact stratigraphic position. Samples were identified instead with labels that do not correspond to stratigraphic position of the sample. However, the paper provided the thickness of each formation where the samples were taken. In order to use this information, I assumed that samples were equidistant across each particular formation. This probably will produce an indeterminate error in the correlation but it is preferred to not using the information at all, given the small amount of published information. Datums used for these two additional sections are shown in Table 5-8, and correlations in Figure 5-13. Datum information from these two sections was not included in the CS because the uncertainty in sample stratigraphic position. The calibration of the CS against the international time table is a difficult task given the lack of published information on planktonic foraminifera and/or magnetostratigraphy in sections where palynological work has been done. Germeraad et al. (1968) mentioned a number of foraminifera associated with their zones (see the discussion in previous studies above). However, they only presented stratigraphic positions of both foraminifera and sporomorphs for three sections (one well and two outcrop sections), all of them from Nigeria. The two Nigerian outcrop sections (Imo and Ovim Bende) do not have a vertical scale, thickness of the formations, or depth of samples. In spite of this problem, the sections were used because they are some the few sections that have both planktonic foraminifera and pollen information. Thickness for each formation was assigned from the type sections for each formation, Imo Shale=~ 1300m, and Ameki=~900m (Nigeria, 1956), that are located near the place were sections were measured. Samples were then uniformly spread along each formation (datums used are shown in Table 5-8). A fourth section, Itori borehole, also is from

PAGE 56

46 o 300 200+ 354 + 36 7 O 137 7 O + 177 100 ,37 c 155 fc 187 o -1 — I — I — I — i — I — I — r100 200 300 m 400 Regadera Figure 5-4. First round of correlation. Pinalerita (Reference Section) versus Regadera. SeeTable 5-6 for the names of the taxa used in graphic correlation. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.

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47 Figure 5-5. First round of correlation. Composite Section versus Tibui. Tibui section after Gonzalez (1967). See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.

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48 5 a u IS) IS, O a. S o U 800 c.u. 700 600 -i 500 400 300 200 ioo c o — o U o E o U o 900 C.U. 800 700 -. 600 -j 500 -j 400 -j 300 200 -j 100 -. 0 ( 184 + Q295 O H2 240 O 255 O -t— i — r— i— i — i— i — i — i — i — i—i — i i i — i—i — r 200 400 600 r m. 800 T4 185 ->13 149 28 \ 282\ +' + 187 + 112 354 + S 9 8 113 57 257 O o 150 246 O O 185 O 234 8 240 188 235 O O 'J? 73 O i M m il III l l II I l l III ll I I I ll I II l l III l l I I I ll III ll I I I II 111 ll III ii in ii ill i i i n ii M i ii III ll I I I l l I II ll I II l l III ll l ioo ^ 200 300 ; 400 500 600 700 ^ 900 m. i ioo Uribe Figure 5-6. First round of correlation. Composite Section versus T4 and Uribe sections. T4 after Rull (1997b). See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Boxes indicate strata down to next lower sample for First appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.

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49 800 c.u. 700 600 500 c o •a 400 u o in u s ft 300 200 100 56 + 112. +131 165 + + 163 + 187 o 90 172 o 112 257 o 187 o T — I — I — I — r— 100 200 ' I ' ' ' 300 m. 400 Regadera Figure 5-7. Second round of correlation. Composite Section versus Regadera. See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Datums of Composite Section derived from Regadera are excluded. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.

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50 Figure 5-8. Second round of correlation. Composite Section versus Tibui. See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Datums of Composite Section derived from Tibui are excluded. First appearance datums= FAD, last appearance datums=LAD.

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51 900 0 100 200 300 -400 500 600 700 800 900 Uribe Figure 5-9. Second round of correlation. Composite Section versus T4 and Uribe. See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Datums of Composite Section derived from T4 and Uribe are excluded.

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52 Pinalerita Figure 5-10. Second round of correlation. Composite Section versus Pinalerita. See Table 5-6 for the names of the taxa used in graphic correlation. c.u.=composite units. Datums of Composite Section derived from Pinalerita are excluded. First appearance datums= FAD, last appearance datums=LAD.

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53 Figure 5-11. Line of correlation for well Tl, Regadera, and Tibui sections versus Composite Section. See Table 5-6 for names of the taxa used in graphic correlation. First appearance datums= FAD, last appearance datums=LAD.

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54 I | I I I I I I I I I | I I I I I II I I | I I I I I I I I l| I I I I I I I I I | II II I I I | M l I l l l l I j I I I I II Ml [ I II I I I II I J I I I I I I I II |l l I I II II | 1(X) 200 300 400 500 600 700 800 900 1000 1100 800 c.u. 700 600 Uribe c o •a u 00 500 ~ a -wo o CE o u 300 -: 200 100 0 UP \6o job 3o\) 4ob sio isob 'vATm/soo Pinalerita viv.-i-^;. ::U^ 3 Figure 5-12. Line of correlation for Uribe and Pinalerita sections versus Composite Section. See Table 5-6 for names of the taxa used in graphic correlation. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account.

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55 Figure 5-13. Line of correlation for Rubio Road and Paz de PJo sections versus Composite Section. Sections after Germeraad et al. (1968). See Table 5-6 for names of the taxa used in graphic correlation. Boxes indicate strata down to next lower sample for first appearance datums (FAD) and up to next higher sample for last appearance datums (LAD) to take large gaps in sample interval into account

PAGE 66

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PAGE 76

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PAGE 77

67 Table 5-4. Palynomorph distribution in samples from the Regadera section Taxa sample code 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Araucariaciates "rugulatus" Baculamonocolpites "curubensis" Bombacacidites "dilcheroi" 1 Bombacacidites "psilatus" 1 Bombacacidites foveoreticulatus Bombacacidites soleaformis Brevitricolpites "microechinatus" 2 Cicatricosisporites dorogensis C. dorogensis subsp. minor forv. rugulatearis Clavatricolpites "densoclavatus" 7 Cricotriporites "macropori" 1 Cricotriporites guianensis 2 Cyclusphaera "scabratus" 1 Echinatisporis "brevispinosus" 1 Echinatisporis? "cingulatus" 3 Echiperiporites estelae Echitetracolpites "echinatus" Echitetracolpites "tenuiexinatus" Ech itriporites " re ti ech i natus " Echitriporites trianguliformis var. "orbicularis" Foveotricolporites "rugulatus" Foveotriporites hammenii Jussitriporites undulatus Ladakhipollenites "gemmatus" 1 Ladakhipollenites simplex Laevigatasporites "laevigatus" Laevigatosporites tibui L proxapertitoides var. reticuloides L proxapertitoides var. proxapertitoides Margocolporites vanwijhei Mauritiidites franciscoi \ai. franciscoi 4 Mauritiidites franciscoi var. minimis Mauritiidites franciscoi var. pachyexinatus 1 Microfoveolatosporis skottsbergii 1 Monoporopollenites annulatus Nothofagidites "huertasi" Nothofagidites "lolongatus" Perisyncolporites pokornyi Polypodiisporites "breviverrucatus" Polypodiisporites "echinatus" 1 1 Polypodiisporites specious Proxapertites magnus 1 Proxapertites operculatus Psilamonocolpites medius 1 4 Psilastephanocolporites "psilatus" 3 25 145 7 1 2 2 1 2 2 1 7 131 2 33 3 7 13 3 19 90 1 25 1 2 10 14 3 6 7 1 7 7 16 3 1 3 1

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68 Table 5-4— continued. Taxa sample code 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Psilastephanoporites "distinctus" I Psilasyncolporites "fastigiatus" 2 1 Psilatricolporites "orbicularis" 1 Psilatricolporites crassus 2 85 Psilatricolporites maculosus 1 5 12 Psilatricolporites transversalis 1 1 Retibrevitricolpites "santanderensis" 3 Retibrevitricolporites "grandis" 10 12 Retimonocolpites "ovatum" 7 2 2 3 7 1 Retistephanocolpites "fossulatus" 1 1 Retistephanocolporites festivus 1 6 Retistephanoporites angelicus 6 1 5 Retisyncolporites angularis 1 1 Retitricolpites "perforatus" 1 Retitricolporites "delicatus" 1 Retitricolporites "vestibulatus" 1 Retitricolporites irregularis 1 2 Retitricolporites mariposus 1 Scabratriporites "bellus" 1 Spirosyncolpites spiralis 113 7 1 Striatricolpites "tenuistriatus" 2 1 Striatricolpites catatumbus 3 1 1 Syncolporites marginatus 1 Ulmoideipiles krempii 1 2 Verrutricolporites "reticulatus" 1 Wilsonipites margocolpatus 1 "Psilatriletes" sp. A 45 2 2 3 13 53 "Psilatriletes" sp. B 17 2 2 2 10 5 "Psilatriletes" sp. C 49 3 2 10 Camarozonosporites sp. A 1 Cingulatisporites sp. B 1 Foveotriletes sp. B 1 Incertae sedis sp. B 1 Laevigatosporites sp. A 1 Mauritiidites sp. A 1 1 Psilastephanoporites sp. A 1 Scabratisporites sp. A 1 Tuberositriletes sp. A 1 Algae 1 Dinocyst indet. 1 Incertae dinocyst A 1 Pediastrum 3 2 8 Polysphaeridium sp. A 14 Circulodinium distinction (RW?) 5 Oligosphaeridium sp. (RW) 1 Proxapertites magnus (RW) 1

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69 Table 5-4--continued. Taxa sample code 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Senegalinium sp. A (RW?) 6 Spiniferites sp. (RW?) 1 Bombacacidites sp. 2 1 Cingulatisporites sp. 1 Clavatricolpites sp. 1 Clavatricolporites sp. 3 Colombipollis sp. 1 Echistephanoporites sp. 4 Echitriporites sp. l Ladakhipollenites sp. l Laevigatosporites sp. 1 Pollen indet. 1 Psilatriporites sp. 1 Retistephanoporites sp. 11 1 Retitricolpites sp. 17 2 1 2 3 Retitricolporites sp. 6 7 1 1 Rugotriporites sp. 1 Scabrastephanoporites sp. 1 Spinizonocolpites sp. 2 Striatricolpites sp. 1 Verrutriletes sp. 1 Key to sample code (meters from base of Mirador Formation) 1 =RE39 (-12m.) 2 = RE 46 (-1.5m.) 3 = RE 49+130 (4.3m.) 4 = RE 67+120 (31.2m.) 5 = RE 83 (54m.) 6 = RE 98 (76.5m.) 7 = RE 113 (99m.) 8 = RE 132 (127.5m.) 9 = RE 143+120 (145.2m.) 10 = RE 153 (159m.) 11 = RE 170+40 (184.9m.) 12 = RE 186 (208.5m.) 13 = RE 190+10 (214.6m.) 14 = RE 220 (259.5m.) 15= RE 222+100 (263.5m.) 16 = RE 241+40 (291.4m.) 17 = RE 251+30 (306.3m.)

PAGE 80

70 Table 5-5. Palynomorph distribution in samples from the Uribe section Taxa sample code 1 2 3 4 5 6 7 8 9 10 1 1 12 13 14 15 16 17 18 19 20 21 22 23 Anacolosidites ariani 1 Baculamonocolpites "angustus" Baculamonocolpites "curubensis" Baculatisporites "soleus" 1 Bacumorphomonocolpites tausae 1 Bombacacidites "psilatus" Bombacacidites "simplireticulensis" Bombacacidites brevis Bombacacidites nacimientoensis Brevitricolpites "microechinatus" 4 Camarozonosporites "inciertus" Chomotriletes minor Cricotriporites guianensis Crototricolpites cf. annemariae 1 Cyclusphaera "scabratus" 1 Echinatisporis "brevispinosus" Echinatisporis "obscurus" Echinatisporis? "cingulatus" Echitriporites "variabilis" Echitriporites trianguliformis var. "orbicularis" Foveotriporites hammenii Gemmamonocolpites "ambigemmatus" Laevigatosporites tibui 2 1 Longapertites proxapertitoides var. reticuloides Longapertites proxapertitoides var. proxapertitoides I Mauritiidites franciscoi var. franciscoi Mauritiidites franciscoi var. minutus 7 Mauritiidites franciscoi var. pachyexinatus Polypodiaceoisporites ? "fossulatus" Polypodiisporites "brevis" 2 Polypodiisporites "breviverrucatus" Polypodiisporites "densus" Polypodiisporites "echinatus" II Polypodiisporites specious Proxapertites cursus Proxapertites humbertoides 2 Proxapertites operculatus Proxapertites psilatus Proxapertites verrucatus 1 1 1 Psilamonocolpites medius Psilastephanoporites "annulatus" Psilatricolporites "orbicularis" 3 Psilatricolporites maculosus Psilatriporites "tenuiexinatus" 1 IS 1 2 1 1 8 5 2 1 1 1 2 2 51 IS 2 3 4 1 1 13 14 11 16 1 1 I

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71 Table 5-5— continued. Taxa sample code 1 2 3 4 5 6 7 8 9 10 1 1 12 13 14 15 16 17 18 19 20 21 22 23 Pteridacidites "cucutensis" 1 1 Racemonocolpites "costagemmatus" 1 Racemonocolpites facilis 1 1 I Racemonocolpites racematus 1 Retibrevitricolpites triangulatus 2 Retibrevitricolporites "grandis" 1 2 Retibrevitricolporites "speciosus" 1 Retimonocolpites "ovatum" 1 9 2 17 1 7 1 Retistephanocolporites fesiivus 2 Retistephanoporites "regaloi" 1 Retitricolporites "delicatus" 1 Retitricolporites "grandis" 1 Retitriporites "poricostatus" 1 Scabratricolporites "amplocolpatus" 1 2 Spinizonocolpites "brevibaculatus" 1 10 3 1 Spinizonocolpites "pachyexinatus" 1 I Spinizonocolpites "pluribaculatus" 1 Spirosyncolpites spiralis 1 1 1 3 1 3 3 10 Striatricolpites "tenuistriatus" 1 1 8 Striatricolpites catatumbus 3 1111 Tuberositriletes "verrucatus" I Ulmoideipites krempii 6 Verrumonocolpites "romatus" 1 "Psilatriletes" sp. A 5 1 11 1 I 1 21 4 4 24 47 "Psilatriletes" sp. B 4 6 11 5 1 5 25 6 3 20 13 "Psilatriletes" sp. C 12 9 1 Acritarcha sp. A l Clavamonocolpites? sp. A 1 Echimonocolpites sp. B I Echinatisporis sp. A 1 Echitriporites? sp. A 1 Foveotricolporites sp. A 1 Gemmainaperturites? sp. A 1 Incertae sedis sp. C 1 Laevigatasporites sp. C 1 Laevigatasporites sp. D 3 Longapertites sp. B 2 Psilastephanocolporites sp. A 1 Psilatriporites sp. C 1 Retibrevitricolpites sp. A I Retistephanoporites sp. B 1 Retitricolporites sp. A I Striatricolporites sp. A 1 1 Syncolporites sp. A I Tuberositriletes sp. A 1 Algae 1 Algae A 3

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72 Table 5-5--continued. Taxa sample code I 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Dinocyst indet. Incertae dinocyst B Incertae dinocyst C Pediastrum Spiniferites cf. mirabilis Alisogymnium euclaense (RW) Buttinia andreevi (RW) Dinogymnium acuminatum (RW) Dinogymnium sp. (RW) Dinogymnium undulosum (RW) Odontochitina sp. (RW) Oligosphaeridium sp. (RW) Palaeohystrichophora infusorioides (RW) Periretisyncolpites giganteus (RW) Proxapertites magnus (RW) Senegalinium sp. A (RW?) Spinidinium sp. (RW?) Spinozonocolpiles baculatus (RW) Stephanocolpites costatus (RW) Bombacacidites sp. Echipollenites sp. Echitriporites sp. Pollen indet. Polypodiisporites sp. Psilastephanoporites sp. Psilatricolporites sp. Retimonocolpites sp. Retipollenites sp. Retisyncolporites sp. Retitricolpites sp. Retitricolporites sp. Stephanocolpate sp. Verrucatosporites sp. Verrumonoletes sp. Verrutriletes sp. Zonotriletes sp. 1 2 I 3 5 1 2 Key to sample code (meters from base of La Paz Formation) 1 =sample UR 376 (-6m.) 2 =sample UR 379 (-4.5m.) 3 =sample UR 395+120 (20.7m.) 4 =sample UR 409+70 (41 .2m.) 5 =sample UR 437+5 (83m.) 6 =sample UR 445 (94.5m.) 7=sample UR 470 (132m.) 8=sample UR 502 (180m.) 9=sample UR 507 (187.5m.) 10 =sample UR 531 + 120 (224.7m.) 1 1 =sample UR 542+40 (240.4m.) 12 =sample UR 545 (244.5m.) 13 =sample La Paz 361 m (361m.) 14 =sample UR 704+10 (385.1m.) 15=sample UR 726 (418m.) 16 =sample UR 761 (470.5m.) 17 =sample UR 781+20 (500.7m.) 18=sample UR 812 (547m.) 19 =sample UR 849 (602.5m) 20 =sample La Paz 712 m (712m) 21 =sample La Paz 886 m (886m) 22 =sample La Paz 989 m (989m) 23 =sample Esm 21 m (1067m)

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79 Nigeria and contained sporomorph information and radiometric dating of a bentonite (Adegoke et al, 1970; Jan du Chene et al, 1978a). Datums for this section are in Table 5-8. These four sections were compared against the Composite Section (CS). The planktonic datums and radiometric age were then projected upon the CS (Fig. 5-14, 5-15, and 5-16). Discussion Biostratigraphers should not expect widespread synchronous first and last occurrences in the stratigraphic record. Many variables like migration, non preservation, barriers, and local extinctions can truncate the geological range of a taxon (Mann and Lane, 1995). Pollen and spores distributions in tropical environments are strongly controlled by the geographic distribution of the plants from which they are coming. However, this fact has not been considered in the palynological zonations proposed so far for the Paleocene-Eocene interval in northern South America. For example, some zones have been based on pollen produced by mangrove elements {Psilatricolporites crassus zone, Germeraad et al, 1968). A zone like that clearly would be controlled by facies, and would lead to the recognition of false "hiatus" in continental areas where mangrove was not present. This may be one of the reasons of the multitude of hiatus proposed during the Eocene in the Colombian-Venezuela region (Colmenares and Teran, 1993). Here, the pollen and spores distribution was analyzed using the technique of graphic correlation. This method dismisses narrative-type scenarios and produces alternative hypothesis that can be expressed in testable forms (Mann and Lane, 1995). Graphic correlation does not make the a priori assumption that first and last appearances in a particular section record speciation and extinction events. By combining the information of multiple sections, the method allows the true stratigraphic range of a taxon to be determined; therefore, the use of an "index" fossil is not necessary as the whole assemblage is being compared. This approach also produces a biostratigraphic framework that constantly can be challenged as

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80 CS P4 800. cu 700 -. 600 -i 500 -j 400 -i 184 22C + 0 336 fvn 0 y ioj 245i 240 0 rTTTF M l|l III I M I I j I III MM Ij I mo 0 400 800 1200 1600 2000 m 2400 Imo shale Ameki T_j_Ogwashi -asaba Planorotalites (Globorotalia) pseudomenardii zone (P4) Morozovella (Globorotalia) velazcoensis/acuta zone (upper P4-P5) (middle P7 ^ to middle P4) OFAD + LAD Jtori 20 1 0 m 0 Ewekoro| Akinbo 54.4+/. 2 .7my (middle P7 ^ to middle P4) Figure 5-14. Line of correlation for Imo section (Germeraad et al., 1968) and Itori well (Adegoke etal., 1970 and Jan du Chene etal., 1978) versus Composite Section. See Table 5-6 for names of the taxa used in graphic correlation.

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81 CS middle P9-P14 700 c.u. middle P6B 600 -. upper P8 500 h 400 -i upper P4P5 300 -.200 100 0 500 . i | i i 1000 1500 m. 2000 1 Imo shale 1 Ameki 7 Truncorotaloides rohri zone (middle P9-P14) Morozovella (Globorotalia) formosa zone (middle P6-P7) Morozovella (Globorotalia) velazcoensis/acuta zone (upper P4-P5) middle P9-P14 ei 't O O FAD + LAD 5000 4500 4000 3500 ft. 3000 Benin Akata lAi 1 Benin Truncorotaloides rohri zone (middle P9-P14) Figure 5-15. Line of correlation for Ovim and Benin section (Germeraad et ai, 1968) versus Composite Section. See Table 5-6 for names of the taxa used in graphic correlation.

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82 Benin Ovim middle P9-P14 Composite Section middle P9-P14 = r 700 pa_p 14 middle P6-P7*3 = = r 600 Imo P4 Itori (middle P4^ to middle P7) [ upper P4-P5 [ Benin upper P4-P5 [ 800 c.u 50.8 L 500 P6-P7 r 400 54.5 r 300 P4-P5 200 -r 100 59.2 u — c -o
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83 new information (more sections) is being produced. On the contrary, "traditional" zonations such as the ones currently used in northern South America, are static and authoritative, strongly relying opon one biostratigrapher's interpretation of the chronostratigraphic importance of a given taxa. Graphic correlation was developed by Shaw (1964) and has been successfully used for many authors and specially by Amoco researchers for many years (Carney and Pierce, 1995). The general sequence of events, first appearance datums (FAD), last appearance datums (LAD), and abundance peaks, of the Composite Section (CS) is similar to those of previous zonations (Table 5-7 for datums, c.u. indicates composite unit). The sequence of Foveotricolpites perforatus LAD (81 composite units c.u.); Retibrevitricolpites triangulatus FAD (245 c.u.); Foveotricolpites perforatus LAD (310 c.u.); Ephedripites vanegensis LAD (312 c.u.); Retidiporites magdalenensis LAD (312 c.u.); Bombacacidites annae LAD (325 c.u.); Cricotriporites guianensis LAD (475.2 c.u.); Foveotriporites hammeni FAD (490 c.u.); Monoporopollenites annulatus FAD (568 c,u.);Cicatricosisporites dorogensis FAD (605 c.u.); Perisyncolporites pokornyi FAD (612 c.u.); Psilatricolporites crassus FAD (637 c.u.); and Rugotricolpites felix LAD (725 c.u.) mostly agrees with previous zonations. However, there are several discrepancies with Germeraad et al. (1968) and Muller et al. (1987) zonations specially within the Eocene. Taxa, which according to these zonations should not be overlapping, are overlapped (e.g., Cicatricosisporites dorogensis and Rugotricolpites felix). Most of the taxa ranges in Muller's and Germeraad's zonations abruptly end or begin at time boundaries (Paleocene/Eocene, lower/middle Eocene, and middle/late Eocene). In the Composite Section (CS), the first and last occurrence events are tied to stratigraphy. This produces a higher time resolution and non-congruence in single stratigraphic horizons of most of the first appearance datums (FAD) and last appearance datums (LAD). Therefore, many of the FAD and LAD sequence of events in the CS do not agree with the Germeraad et al. (1968) and Muller et al. (1987) zonations

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84 where taxa appear in pseudo-bursts of speciation events (e.g., Paleocene/Eocene boundary with 25 new taxa). This probably is also helped by the higher level of resolution of the CS versus previous zonations. It is also noteworthy the increasing of first occurrence datums above 550 c.u. (probably Eocene, see discussion below) that had been noted already by many authors (Leidelmeyer, 1966; Gonzalez, 1967). The CS has low sample resolution between 330 and 390 c.u. and between 500 and 600 cu. due to the sterility of most of the samples in the Pinalerita section (upper Arcillas de El Limbo, lower Areniscas de El Limbo Formations), in the Regadera section (upper Cuervos, lower Mirador), and in the Uribe section (upper Lisama, lower La Paz Formations, see Tables 5-3, 5-4, and 5-5). Information for this interval, however was supplied by Tibui section (Gonzalez, 1967). Correlations of these sections against the composite (Figs. 5-11, 5-12), indicate that there is not a significant hiatus associated with the Mirador/Cuervos, La Paz/Lisama, or Arcillas de El Limbo/ Areniscas de El Limbo contacts, at least in the localities studied. Many authors since the fifties have associated this contact in Colombia with a major hiatus that would encompass 16 my, the entire early to middle Eocene (Morales, 1958; Schamel, 1991; Dengo and Covey, 1993; Cooper etal., 1995; Ramon and Cross, 1997; Suarez, 1997a; Suarez, 1997b; Villamil and Restrepo-Pace, 1998). This idea is deeply rooted in Colombian literature and nowadays constitutes a "pseudo-dogma". However, an intensive literature search has not given even a single locality with fully documented paleontological information supporting this hypothesis, some localities with palynological information have not registered this hiatus (Gonzalez, 1967 in Catatumbo area, and Colmenares and Teran, 1993 in Maracaibo Basin). It could be possibly that in the files of oil companies exist enough evidence supporting this hiatus; however, the graphic correlation of the three sections studied and the Tibui, Rubio and Paz de Rio sections (Figs. 5-1 1 to 5-13) does not indicate a major hiatus encompassing 16 my. Julivert (1961) also pointed out the lack of paleontological evidence supporting this hiatus in the middle Magdalena area and conclude that the time-

PAGE 95

85 gap, where present, would be isochronous with the accumulation of the Lisama Formation (Paleocene), because Lisama is absent from anticlines axis, and in angular unconformity above Cretaceous sediments in anticline flanks. The time-gap would not be between La Paz-Lisama as previously assumed but during the accumulation of Lisama. I would argue that one of the reasons that is producing the perception of this hiatus is that samples above and below the assumed hiatus are generally sterile for palynomorphs. This would produced an artificial gap in time because of the absence of traditional pollen zones present within the sampling gap. The possibility of an important hiatus is, however, still an open question. One of the most difficult tasks in biostratigraphy is calibrating the Composite Section (CS) with the geologic time scale. The Paleocene and Eocene epochs and their ages are defined by planktonic foraminifera, calcareous nannoplankton and magnetic polarities. The chronostratigraphy of Berggren et al. (1995b) for the late Paleocene and Eocene is followed here (Fig. 5-17). The planktonic foraminifera zonation is that of Berggren etal. (1995b). Most of the epoch/series and stage/age boundaries of the late Paleocene and Eocene are relatively well established with the exception of the Paleocene/Eocene boundary that still does not have a Global Stratotype Section and Point (GSSP). The Paleocene and Eocene series terms were defined in 1874 and 1833 respectively (Berggren and Aubry, 1998). The boundary awaits determination of a GSSP within the 2 my time span between the top of the Thanetian Stage and the base of the Ypresian Stage. The difficulties in defining the boundary are caused by the multitude of unconformities and facies changes at the base of the type section of Ypresian Stage in Belgium (base of leper Clay of the Belgian Basin that is equivalent to base of the London Clay Formation in London/Hampshire Basin). The base of the Ypresian Stage/Series in these two localities is separated from top of Thanetian Stage/Series (Thanet Beds, London Basin) by an stratigraphic interval where Paleocene/Eocene boundary would be located (Berggren and Aubry, 1998). This interval encompasses from NPlOa/b

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86 boundary, base of Ypresian (54.37 my) to the top of Thanetian (56.6 my). Several events within this interval are suggested to denote the Paleocene/Eocene boundary (Berggren and Aubry, 1998). Planktonic P5/P6 boundary (54.48 my), N9/N10 boundary (55 my), benthic foraminiferal extinction (55.5 my), and delta 13 C isotopic excursion (55.5 my). Here, the planktonic P5/P6 boundary (54.48 my) is chosen as the Paleocene/Eocene boundary (Fig. 5-17). Few elements are available to calibrate the CS. Germeraad et al. (1968) paper stated a number of foraminifera taxa recorded from sections in Colombia and Venezuela (see Fig. 5-2 and text in "previous studies"). Unfortunately, the paper did not indicated the precise stratigraphic position of any of those foraminifera taxa. Therefore, they cannot be used in the graphic correlation methodology. Germeraad et al. (1968) only presented stratigraphic positions of foraminifera from sections in Nigeria. These were the information used to calibrate the CS developed in this study. Germeraad et al. (1968) and subsequent reaearch in Nigeria (Adegoke and Jan du Chene, 1975; Jan du Chene and Salami, 1978; Jan du Chene et al, 1978a; Salami, 1985; Awad, 1994) have noticed floristic similarities between northern SouthAmerica and tropical Africa during Paleocene and Eocene times. These authors also have used, to some extent, the Germeraad et al. (1968) zonation. Therefore, correlations with the Nigerian sections probably would provide a general idea of the timing of pollen and spores succession in northern South America until further research in the area is done. The Imo and Ovim sections contain the Planorotalites (Globorotalia) pseudomenardii zone that is equivalent to P4 zone of Berggren et al. (1995b), and the Morozovella velascoensis/Morozovella acuta zone that is equivalent to the upper P4 to P5 zones of Berggren et al. (1995b) (see Figs. 5-14, 5-15 and 5-16; taxonomy after Tourmankine and Luterbache, 1985, taxa ranges after Tourmankine and Luterbache, 1985 and Berggren et al, 1995b). When projected in the CS, the foraminifera indicate that the interval P4-P5 is located between composite units (c.u.) 0 to 410 (Fig. 5-16). The

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87 Time (My) Epoch Age Plankton zones Chrons Figure 5-17. Berggren et al. (1995) chronology of the late Paleocene-Eocene epochs. Dashed lines at 55.5 My reflects current opinion on the position of the PaleoceneEocene boundary. Taken at the base of the type Ypresian in Belgian basin or the London Clay in London Basin it position would be at 54.6 to 54.8My.

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88 position of the Paleocene/Eocene boundary is then tentatively located at c.u. 420, although it could be located in an interval between 410 and 475, because the sample at 477 meters in the Pinalerita section (c.u. 475) contains an assemblage that lack typical late Paleocene taxa as Foveotricolpites perforatus, Retidiporites magdalenensis, and Bombacacidites annae. This late Paleocene age given to the 0-410 c.u., is also supported by the radiometric dating of a bentonite (Adegoke et al., 1970; Jan du Chene et al, 1978a) that yielded an age of 54.4+/2.7 million years equivalent to middle P7 to middle P4 planktonic zones (Figs. 5-14, 5-17). The early Eocene is recognized by the projection in the CS of the Morozovella formosa zone of Germeraad et al. (1968). They did not state how this zone was identified, therefore, I took the conservative approach of considering the total range of M. formosa-formosa, (middle P6 to P7 after Berggren et al, 1995b), as the chronostratigraphic significance of Germeraad et al. (1968)M. formosa zone (Fig. 5-17). Therefore, the early Eocene (zones P5 to P7) would be represented between composite units 420 to 590 (Fig. 5-16). The uppermost early Eocene and middle Eocene is recognized by the Germeraad et al. (1968) Truncorotaloides rohri zone. They did not state how this zone was recognized, therefore here I take the conservative approach of considering the whole range of T. rohri (middle P9 to P14 after Tourmankine and Luterbache, 1985) to denote the chronostratigraphic significance of the "T. rohri zone". In this scenario the latest early Eocene and middle Eocene would be present above 590 up to 670 c.u. Calibration above 670 c.u. is not possible due to the lack of foraminifera data. An alternative hypothesis would be to consider the T. rohri of Germeraad equivalent to T. rohri-M. spinulosa Partial Range Zone (P14) of Berggren et al. (1995b). This hypothesis would indicate an extensive time condensation (-10.8 my), between c.u. 590 and 670, top of P7 to base of P14 (see Figure 5-16). This condensation, however, is not supported by the stratigraphic position of this composite unit (c.u.) level in Uribe,

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89 Regadera, Tibui, Tl sections (Figs. 5-11 and 5-12, Appendix B), where lithology does not indicate an extensive hiatus. This level in the Pinalerita section is associated with a transgressive surface (see discussion in Sequence Stratigraphy below) and probably some time condensation (Fig. 5-12). Therefore, the possibility of an early to middle Eocene hiatus still exists but further research is necessary to address this specific issue.

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CHAPTER 6 SEQUENCE STRATIGRAPHY Sequence stratigraphic is the study of genetically related facies within a framework of chronostratigraphic significant surfaces (Van Wagoner et al, 1990). The "sequence" is its basic unit that is defined as a relatively conformable, genetically related succession of strata bounded by unconformities or their relative conformities (Van Wagoner et al, 1990). A parasequence is the building block of a sequence and is defined as a relatively conformable, genetically related succession of beds or bedsets bounded by marine-flooding surfaces or their correlative surfaces (Van Wagoner et al, 1990). A sequence stratigraphic analysis requires many different types of information (sedimentary, biostratigraphic, seismic) to fully understand the stacking pattern of parasequences in lowstand systems tract (LST), transgressive systems tract (TST); or highstand systems tract (HST), and the recognition of important surfaces (MFS: maximum flooding surface, TS: transgressive surface, and SB: sequence boundary). In this study, I combined three different types of information (palynofacies, paleoecological analysis of palynomorphs, and lithological analysis) to produce a "paleobathymetric" curve (a curve that represents the relative movement of the coastline in relation to a fixed point that is the section studied), and a sequence stratigraphic interpretation for each of the three sections. In the following headings (Palynofacies, Paleoecology, and Lithology), I will present and discuss each type of information. At the end of this chapter (in "Sequence Stratigraphic Interpretation"), they will be combined and a sequence stratigraphic model will be proposed for each stratigraphic section. This analysis does not include a reconstruction of the regional geometry of the entire basin. The purpose here is to produce well-supported stratigraphic hypothesis, with age control, that can be 90

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91 used to test previous sequence stratigraphic models and can be used in the future as reference points. One of the most problematic issues in the Paleogene geology of Colombia is the lack of well-supported models (age, environment, sequence stratigraphy) for individual sections. Most of the published work consists of regional summaries and models without well-documented data, especially lacking paleontologic data, supporting those interpretations (e.g., see Cooper et al., 1995). The other major problem hampering a clear understanding of Tertiary stratigraphy of Colombia has been the lack of stratigraphic nomenclatural consistency that has lead to naming a formation with several names, or different formations with the same name (Porta, 1974). Correlations are often done based on lithology and formational names sometimes creating stratigraphic chaos (Porta, 1974). One of the biggest misconceptions about sequence stratigraphy is that one must accept the validity of eustatic sea level curves (Haq et al, 1988) to use sequence stratigraphy. However, as Weimer and Posamentier (1994) pointed out: "regardless of whether one accepts or rejects the published global curves, it is important to realize that this debate does not affect the other major, and much more important, aspect of sequence stratigraphy: i.e., lithology prediction". Stratum hierarchy and distribution predicted by sequence stratigraphic models are produced in response to variations of relative sea level rather than solely eustatic changes. Therefore, the sequence stratigraphy model will apply whether or not eustasy is driving the generation of space available for accumulation of sediments through time. Palynofacies Previous Studies Palynofacies is defined here as the microscopic organic constituent of a rock (Combaz, 1964). Palynofacies analyses have been used in many studies to identify depositional environments (Batten, 1973; Hart, 1986) and in sequence stratigraphic

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92 analysis (Batten, 1973; Hart, 1986; Gregory and Hart, 1992; Blondel et al, 1993; Habib et al, 1994; Jaramillo and Oboh, 1999). Important factors controlling the distribution and preservation of particulate organic matter are energy in the area of deposition, water table position, and the oxidation potential of the water-sediment interface (Batten, 1973; Hart, 1986; Lorente, 1986; Batten, 1996). Higher levels of oxygenation of the sedimentwater interface increase the degradation of organic matter while anoxia preserves particles and its internal structures (Lorente, 1986; Batten, 1996). Other factors as climate and microclimate, local and regional vegetation, water characteristics, soil biota, and sedimentation rate also affect the composition of the palynofacies. However, several trends can be identified along the fluvial-coastal-nearshore environmental gradient. These trends can be used to identify shifting depositional environments through time (Lorente, 1986; Jaramillo and Oboh, 1999). Few studies specifically addressing palynofacies analysis are available from tropical regions, where vegetation types are different and rates of degradation of organic matter are higher (Batten, 1996). Lorente (1986; 1990) in a pioneer work for palynofacies from tropical regions, developed a number of models for fluvio-deltaic and nearshore environments in the Orinoco delta. Muller (1959) also studied the Orinoco delta only focusing on the pollen, spore, and dinoflagellate distributions. Risks and Rhodes (1985) studied palynofacies of mangrove environments in tropical Australia; Bustin (1988) studied the palynofacies of the Tertiary of Niger delta; Van Waveren and Visscher (1994) studied the organic matter of surficial deep-sea sediments in Banda Sea, Indonesia; and Gastaldo et al. (1996) and Gastaldo and Staub (1997) studied palynofacies of modern sediments in the Rajang river and delta in Malaysia. Results The results for the point count of organic matter particles are shown in Tables 6-1, 6-2, and 6-3. Using the thickness of each stratigraphic section as scale, the relative

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93 frequencies of the organic matter types in the three sections were plotted in Figures 6-1, 6-2 and 6-3. Euclidean-distance cluster analysis for the Pinalerita section identified six groups of samples on the basis of their organic matter content (Figs. 6-4, 6-5). Group 1 is characterized by a high dominance (more than 60%) of black debris. Group 2 is characterized by a dominance of yellow brown plus black brown, plant tissue and sporomorphs. Group 3 is characterized by a codominance of plant tissue and black brown, with occasionally high abundance of sporomorphs and dinoflagellates. Group 4 of samples are codominated by black debris and black brown. Group 5 is dominated by plant tissue with moderate abundances of dinoflagellates and sporomorphs. Group 6 is characterized by yellow brown organic matter. There is not a strong correlation between sample lithology and palynofacies content (see lithofacies and cluster groups in Figure 64). Similar lithofacies, therefore, could produce different palynofacies. The organic matter data from the Regadera and Uribe sections were combined into a single analysis because they were probably accumulated in similar environments (Notestein etai, 1944; Porta, 1974). Therefore, organic matter could be distributed in a similar way across the diverse subenvironments of the fluvial environment. The Euclidean-distance cluster analysis for the Regadera and Uribe sections identified five groups of samples on the basis of their organic matter content (Figs. 6-6, 6-7). Group A is dominated mainly by yellow brown organic matter. Group B is characterized by high percentages of plant tissue, with moderate abundances of sporomorphs and black debris. Group C is dominated by black brown with moderate abundances of yellow brown and black debris. Occasionally moderate abundances of sporomorphs are present. Group D is dominated by black debris with moderate concentrations of plant tissue and black brown. Group E is characterized by a total dominance of black debris. There is not a strong correlation between sample lithology and palynofacies content (see lithofacies and

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94 of palynofacies groups 0 0 0 0 m l l y 800 r r 50 1000 50 0 5000 50000 _L±_L_LLLU I I I I I 1 I !l 1 I I I I 1 I I 14 Lu y I I LI Environment =P -|3 _»'• . 3 :S. -II -13 -14 I' =|-» -H ZI3 uc i i /i > J L s=sterile RFluvial UC: upper coastal plain LCrLower coastal plain-Inner Self Figure 6-1. Palynofacies of Pifialerita section showing abundances of each organic matter type, palynofacies groups from cluster analysis, and paleoenvironmental interpretation

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95 palynofacies ^ V V V ^° ^ jfQ&A Environment ^ 0>~ c,V" 0 0 0 50 0 50 0 % 50 50 1 h I .... I ... I . . I . . I U_i W 1 L m. 350 300 250 200 150 100 50 — C — D — B — C — B _C — B -D -A IB -C EB .B •D i D -B -B -E — E — E =S s=sterile L/C Sw S:oxidized floodplain, sandbars L: Levee, crevasse splay Sw:Swamps O: oxbow, lake F: Fluvial plain C: Coastal plain Fi gure 6-2. Palynofacies of Regadera section showing abundances of each organic matter type, palynofacies groups from cluster analysis, and paleoenvironmental interpretation

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96 F:old floodplain, sandbars Sw:S\vamps, channel-fill L: Levee, crevasse splay O: Oxbow, lake F: Fluvial plain C: Coastal plain Figure 6-3. Palynofacies of Uribe section showing abundances of each organic matter type, palynofacies groups from cluster analysis, and paleoenvironmental interpretation.

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97 DISTANCE METRIC IS EUCLIDEAN DISTANCE AVERAGE LINKAGE METHOD Palynofacies Tree diagram groups 0.000 Distance lithofacies samples t bm P234 or PI 78.2 1 1 P160.2 P324 gst PI 96.2 gm P81 fs P-3.6 fs P-54 bs P702.9 brc P7108 2 gill P752.6 £ s FVtRQ 4 ruo7.t P46.8 " sl P37 P696.6 fs P636.6 P7383 P766.8 fs PI 54.8 _.M1 P131.4 3 Ml P^i l J. 7 gs P660.6 gc P758.6 gm P775.6 g s P784.8 fs P203.4 gm P5.4 4 gm P30.6 fs P214.2 gm P266.4 gs P733.7 bs P715.6 5 gs P724.9 be PI 05.3 gm P673.8 gm P639 6 gm P682.2 3-, 1 50.00 Lithofacies kev bc=black claystone brc=brown claystone gc=grey claystone brm=brown mudstone bm=black mudstone gm=grey mudstone gem=green mudstone ym=yeIlow mudstone bs=black shale gs=grey shale gst=grey siltstone fs=fine arenite Figure 6-4. Average linkage cluster analysis (with Euclidean distance) of palynofacies in the Pinalerita section. Each palynofacies group represents a group of samples with similar organic matter content, which accumulated in a similar environment. Lithofacies for each sample is provided

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98 Palynofacies Group 50 % 100 Liu luu tiwJ I l I I I t I I I i I I— 50 •so ' ' L 50 ' in 50 _l I , In, t 1 F r r I 5 ' i : l 6 r F Ik \ . r ' Figure 6-5. Organic matter content of each of palynofacies group identified by Euclidean cluster analysis of Figure 6-4 for Pinalerita section.

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99 DISTANCE METRIC IS EUCLIDEAN DISTANCE, lithofacies Distance Palynofacies group B D 1 0.000 sample AVERAGE LINKAGE METHOD 50.00 wm gm gm gm gm fs bm gm fs fs g C brm gm fs bm fs fs fs c bs ms fs bm bm fs Is gm fs bs bm rm fa _[s_ bs gc bm gm c gc cs gm fs C c 3 =3l R 160.5m 'R2 11.5m RI29m R 130.5m R151.5m — R84m — R 115.5m U547m R222m R291.4m R96m R159m R 100.5m U500.7m R 127.5m — 1 U224.7m "R263.5m R99m R306.3m R 145.2m _R2 14.6m U41.2m U180m U385.1 U361m R 112.5m R99.5m U362m U186m U427m U418m U608.5m R171m _R297m U886m in 1 m 1 m 1 1 y U470.5m — I U712m— I R31.2m— ' R144m U871m — I U187.5m— 1 R49.5m -• R76.5m -fl U20.7m -H_ U2 18.5m— ' Lithofacies key c=coal gc=grey claystone brm=bro\vn mudstone bm=black mudstone gm=grey mudstone rm=red mudstone wm= white mudstone bs=black shale fs=fine arenite ms=medium arenite cs=coarse arenite Fi gure 6-6. Average linkage cluster analysis (with Euclidean distance) of dispersed organic matter in the Regadera and Uribe sections. Each palynofacies group represents a group of samples with similar organic matter content, which accumulated in a similar environment. Lithofacies for each sample is provided.

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100 Palynofacies Group n 4* t A 0 0 0 50 % 0 50 0 50 0 0 50 ttti I , , | , 1 i |y I I I , , 1_ i i i i i> B t L Figure 6-7. Organic matter content of each of palynofacies group identified by Euclidean cluster analysis of Figure 6-6 for Regadera and Uribe sections.

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101 G o a 'm c a om. o tOta woody issue lant I a jj o cut own lack -own low "u >, debr ria lack Terres! E/i c K O c '•5 Aquaticmeters amorphous Sample number O m d d CM CI d d tN C"i O fS ts on c d d CM O d d o o d d m so r-p o\ d d d — d d o o o odd f00 oo d rfi H ros n 2 n rrd d u~>ciddddddddd O IN * "1 q * oo 00 vO O O O d d d d d so o on — d — : o o o odd — ^ o. : >n rO SO Tt 00 CM — cm so m so r-" — < rC 00 d cs d d d SO o c so DC sC d oc in m CS ro d d d ON OC tN o oc OC d cm tN ts CN rn O c o en d d c d d o o oc -r q tN d cl to rso cm so r~ d r~ ~ cm so d^tNro — r^r^tNcodd — r^^ro Tfr f<-> CO r~ ° — NOOOOMrtinwvO tNtoOsOOONOocoppOONpO rodo'dx-iooo'dd — oddd 0000000000000000 do'dddo'dddoddo©© d CM rn oo o o d d o o d d sC d o d DO CS sC d oc o o d o o o o o o dodo c"i r-; o o p o o d t^i d d d d d o o d d Tj; SO tN Tjin o' ~
g _u _u ju u u « u 55 55 55 55 Tt o MN Tt oi so oo o t> r~ O oo ts Tfr tjm u-i so o — — so — Trmu-ic-imos ooo-Tfins9>ooofJTt — tNtNtNtNCNtNCNCOlT) zzzzzzzzzzzzzzzzzzzzz

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102 c a E c u. c c >> •a c o & u 3 I) > u o c 3 Si 3 C c S — O — O c oc rts en q 0> r-» d ts d d d d d fi ts ts DC oc r-"1 m vq "1 <* >* d rn rn in vOOO>000>r^Osf^rnOCSr^roqqqp d d d c id d — d d d d — d d d d d d — r* «S Ov t*l in >/-i u-i r~ (S o in CJ\ in rn oc d dc c4 DC oc 00 t*i ir, <* ts fS do'dd—-— -000000 dodo d * o On m iri oc ts ts fSoso> — o q oo « in •— ^o'^inNNuioooditin
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103 2 1 U ° JO u, CO £ E— a JO — — 73 -o i u 'C o M u *— • eej o c O u JO u TO o c eej Oh ts I so JO eg £ y '5 M bo g c c e u H 05 3 H O a S i 3 0 £^ £ c o ts Q q o ci o c ri d d d d d d d d d d d d d d q q q ci ci C) ci ci r) q q oc q rC) ON ts ts r*-\ d CI d « — 1 ^> Q Q o Q Q Q Q ci d d d d d d d d d d d d d d d d d d o> nC o o in ts I** 3o OC d t~ 00 d d ci d d CI d s o> -f m t rj -3" (S ct in CI OJ c o o o O o C o o O a o c o O o d d d d d C d d d d d d d d d d d d oc r~ <*! ci oc O nc Cl rrq * wi r~ ci ci ci ri d d <* d -r c! ci CN r j rrs SO o q oc o "1 ts [— d oc oc Q f — fS IS Q Q 1 — 1 vC rin ci rvC ON On a nC <* CI CI CJ Cj >» vC -r d d d -f d OC ci oc ON d d r> ri oc r00 DC ci ct « CI C-4 C o m c m o o O c a ci m q a c o O O d d d d d d d d d d d d d d d d d d c c o c © c o o o nc c c O o O c o c d d d d d d d d d d d d d d d d d d o o o c o o o c o a c o C c O o c c o d d d d d d d d d d d d d d d d d d d u o CJ u u u u C C C iU O «j u u
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104 w u u o H a E i •o c c a 3 cr O O CI odd CN o c d CN NO m r<-> On TICS O O odd — • On in no ci in in — ^ rn d — ' — CN p cn O NO O odd o o o d d o" o o o odd o o o o d <6 di d> ron oo rno -d 1 d d o o o o d d d d IT) CN — ; CN 00 00 NO — — o o o o dodo m NO fl 00 O 00 On h (N| DO d\ NO CN CN oo in on on od in 00 ON CN CN in CN on in p in on d d ci o o o o d d o" d o o o o ci ci <5 ci o c/5 in no o m — rt-' CN on — — cn >n CN CN CN CS >n ci — '• r~ no' nO On On O CN CN CN O + oo o >n o 00 ON ON CN O O O — rt + + CN — CN Tt — — — CN CN CN CN O CO + in CN W — — — Oi OS OS OS OS OS OS OS

PAGE 115

105 g 'u 5a o u H 3 cr «< a. E 9 c/2 a c c 3 c £\ 0 O UO d — O CS d — o o o" d d ro c c d d o d cs CS CS ON n cs o CM O — r+ + NO ON O U0 ON r~ r~ oo on o m ro ro m tjOS ft! 04 g 5 5 5 5 d 00 od ON "™ no roo 00 00 — — — cs m 5 c rCS NO o o OS 2£ 5 5 5 c d roOOrororo'*''* odd odd — cs NONONCNO — vO ON I/O dodes — cscs — ooorooooo d d d d d o" d d ocr^ooTfu^csNOoo TfoduSod^ONvS^" — cs cs cs ci n oooooooo d d d d d d d d ro ro ro in O On r~ — r~ cs cs — no ro cs vO — — cs cs "1 ^ ~~. °°. *i °°. °i i/o — no roO ON vo uS csoNONONoor^r--oo OOOnOnCSIO — CSTt i/i^-mininr^csco rororovOOroroO didic5d> oooooooo d d d d d d d d o o o d d d i i 03 03 o u~i no r
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106 'S c a •om. lods woody ssue lant o. ICS o cut 'own XI lack X own X low yel debri Terrestrii _^ o (3 X C t/: , '-J o c 'o Aquatic meters amorphous nple nber Sar nuri O Os d d 1^1 o o d d rso o o d d rso "1 **J o o d d o o d d c c c c u u 1) U t t t fc A A d d 03 03 03 CQ O s£) Os so O • oo oo so so rp. oo os o o o oo E E C-oo oo SO Os 00 00 E E E E VI VI a tu E £3

PAGE 117

107 cluster groups in Figure 6-6). Similar lithofacies, therefore, could produce different palynofacies. Increasing thermal alteration darkens particles (Traverse, 1988), however, the entire sections seem to be thermally immature according to the yellow color of trilete psilate spores (Thermal Alteration Index: 2 to 2-), therefore thermal alteration would not be a major factor when considering the organic matter distribution across the stratigraphic interval studied. Discussion Generally, the dispersed organic matter content of sediments from neritic, marginal marine, and lower coastal environments consists of two main components: organic matter derived from the continent (terrestrial in the classification, see Table 3-1), and organic matter produced in the ocean, such as dinoflagellate cysts and marine amorphous organic matter (Lorente, 1986; Traverse, 1988). Terrestrially-derived organic matter behaves like a clast in water, therefore, their abundance will decrease as the distance from the land increases. This is the basis for using palynofacies as indicators of variations in the distance to the shoreline, which ultimately can be related to changes in relative sea level. However, stochastic events such as retransporting of organic matter by oceanic currents and storms, palynomorphs transported by the wind, as well as changes in run-off and climate, can also have an influence on the organic matter content of sediments (Batten, 1996). The sample groups of the Pinalerita cluster analysis (Fig. 6-4) could be ordered in an ideal gradient from fluvial/coastal to nearshore environments in the following manner. Barren samples could be associated with environments where seasonal subaerial exposure destroys all organic matter such as flood plains and sand bars (Lorente, 1986; Rull, 1997a). Groups 4, 1,6, and 2 correspond to diverse subenvironments within fluvial system. Group 1 characterized by black debris that generally accumulate in

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108 environments with well-oxygenated sediments where water table fluctuates periodically, such as in levee, point bar, proximal crevasse splay, and channel sand deposits (Boulter and Riddick, 1986; Pocock et al, 1988; Van Vergen and Kerp, 1990; Tyson, 1995; Batten, 1996) . This type of organic matter, however, also could be found in levees and point bars in coastal plain systems (Lorente, 1986; Batten, 1996) or in barrier/beach and offshore sands (Bustin, 1988). Group 4 of samples (black debris and black brown) and Group 6 dominated by yellow brown organic matter accumulated in relatively aerobic environments where particulate organic matter was partially degraded. Dominance of this type of organic matter is frequent in channel-fill deposits and swampy areas (Batten, 1973; Lorente, 1986). Group 2 is characterized by yellow brown coupled with black brown, plant tissue and sporomorphs (the ecological significance of sporomorphs is analyzed in detail in next heading). This assemblage is generally found in lakes and oxbows generally in fluvial but also in coastal deposits where preservation of organic matter is enhanced by low oxygen, and permanent saturation of sediments (Lorente, 1986; Cohen etal, 1989; Batten, 1996). Group 3 probably accumulated in upper coastal plain deposits. Codominance of plant tissue and black brown, with occasional presence of marine dinoflagellate cysts is common in upper coastal plain deposits (Muller, 1959; Lorente, 1986). Plant tissue is usually abundant and well preserved in this type of environment especially when the coastal plain has mangroves associated (Bustin, 1988; Cohen et al, 1989; Jaramillo and Bayona, 2000). Coastal plain is defined here as the coastal land under tidal influence. Group 5 suggests lower coastal plain to innermost shelf conditions. High dominance of plant tissue with moderate abundances and diversity of marine dinoflagellate cysts is common in this type of sedimentary environments in tropical and subtropical regions (Lorente, 1986; Tyson, 1995; Jaramillo and Oboh, 1999). Plant tissue is usually abundant and well preserved in this type of environments where mangroves are productive and export large amounts of organic detritus to tidal creeks and nearshore

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109 environments. This detritus is largely protected from oxidation thus suffering little chemical breakdown, specially in distributary banks and channels, inshore low-tide intertidal, and bay-bottom sandy muds as has been found in tropical Australia (Risks and Rhodes, 1985), the Niger delta (Bustin, 1988), the Orinoco delta (Muller, 1959; Scheihing and Pfefferkorn, 1984). Assemblages recovered in saltwater-influenced areas have a larger proportion (up to 10 times) the amount of structurally preserved matter than in freshwater as was found in Malaysia (Gastaldo and Staub, 1997). A "paleobathymetric" curve for the Pinalerita section was constructed based on the stratigraphic arrangement of these groups (right side of Figure 6-1). This "paleobathymetric" curve shows the variation of the shoreline, and concomitant change of environments, in relation to a fixed point (the geographic location of the section). In environments that are entirely continental, as in the Regadera and Uribe sections, organic matter must be analyzed in a slightly different manner. In continental systems the position and fluctuation of the water table exert a large influence in the preservation of the organic matter (Lorente, 1986). In general, the water table is progressive closer to the surface in environments closer to the coastal plain toward the ocean (Galloway and Hobday, 1996). Therefore, in a given fluvial profile, the dispersed organic matter would tend to be better preserved seaward. This is the basis for identifying variations in gross depositional environments using the organic matter groups produced by Euclidean analysis. Each subenvironment in fluvial environment possesses a characteristic type of organic matter that is mainly the product of the vegetation surrounding the place of accumulation, and the levels of energy, oxygenation, and saturation present during the accumulation of the organic matter (Lorente, 1986). However, the same depositional environment could also have different palynofacies due to differences in the geochemistry of the system (Gastaldo et al, 1996); thus a channel deposit in the alluvial plain may have a different palynofacies than a similar channel in

PAGE 120

110 the coastal plain as was showed by Gastaldo et al. (1996) for the Rajang river and delta in Malaysia. The palynofacies groups identified in the analysis of the Regadera and Uribe sections (Fig. 6-6) were probably accumulated within fluvial environment. Organic matter offers no indications of marine influence in these sections. The interpretation of the environmental significance of each organic matter group is as follows. Groups A (yellow brown), C (black brown), and D (black debris with plant tissue) are typical of channel-fill deposits or swampy areas (see discussion for Groups 4 and 6 above). However, various states of saturation and oxidation within these subenvironments can modify the degree of alteration of the organic matter (Tyson, 1995). Group B (plant tissue, with sporomorphs and black debris) probably accumulated in lakes or oxbows lakes (see discussion above for Group 2). Group E (black debris) probably accumulated in levees, sand bars, or proximal crevasse splay deposits (see discussion above for Group 1). In general terms, group E and sterile samples would tend to be abundant in more upper fluvial environments, where the water table is deeper, and oxidation of organic matter is stronger (Galloway and Hobday, 1996). Groups A, C, and D would tend to be more abundant in intermediate areas of fluvial environment where organic matter, although partially degraded, is still preserved. Finally, group B would be in lower fluvial to coastal plain environments where organic matter tends to be better preserved. "Paleobathymetric" curves for the Uribe and Regadera sections were constructed based on the stratigraphic arrangement of these groups (right side of Figures 6-2, 6-3). This "paleobathyemtric" curve shows the variation of base level, and concomitant change of environments, in relation to a fixed point (the geographic location of the section).

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Ill Paleoecologv Previous Studies The pollen/spores record appears to provide an excellent measure of local to subregional vegetation (Traverse, 1986). Pollen transport, especially in dense tropical rainforests, is limited, and can be expected to be confined mostly to the plant community of origin (Kam-biu and Colinvaux, 1988; Wing and DiMichele, 1992). Most of the extraneous elements are introduced by water rather than wind, especially in active channel deposits, or oxbow lakes that are periodically flooded. Major biases result from different rates in pollen production (Wing and DiMichele, 1992) that can over or underrepresent a taxon in an assemblage. In lowland tropical rainforests, however, studies have shown that there is a good agreement between the pollen/spores assemblages found in the sediment and the vegetation communities near the site of deposition, and that the few wind-pollinated taxa in rainforests do not dominate pollen assemblages (Kam-biu and Colinvaux, 1988). The ecological significance of extinct palynomorph assemblages can be inferred in two basic ways: by analogy of its members with living relatives, or from the spatial distribution of fossils, taphonomy and sedimentary environments. The first method is not very reliable in pre-Neogene sediments (Traverse, 1988) because it is very difficult to assess the natural relationship of fossil taxa, and even if pollen grains are identical, it does not necessarily mean that they were produced by the same plant, or that the taxon was living in similar paleoecological conditions as today. However, in some cases (e.g., Nypa pollen and its fossil pollen counterpart Spinizonocolpites) the ecological significance of a taxon has been securely assessed (Germeraad et al, 1968). The second method is the use of multivariate statistics. The use of multivariate statistical techniques relies on the assumption that co-occurring palynomorphs lived in similar environments and/or were subject to the same depositional processes. Statistical parameters, then, help to evaluate the strength of a given co-occurrence. This approach allows us to test previous

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112 hypotheses on specific palynomorph paleoenvironments. Also it can provide new hypothesis of palynomorph-environment relationships that can be tested in future studies. Most paleoecological studies of Paleogene pollen/spores taxa in the tropics have used the first approach, i.e., analogy with modern relatives. Only three papers have used some type of statistical analysis of the sporomorph distribution (Hoorn, 1994; Rull, 1997a, b). The paleoecological significance of the taxa found in this study are shown in Table 6-4 and are based upon an extensive literature review. Results A non-metric multidimensional scaling (MDS) was performed on a subset of data from the original distribution range charts (Table 6-5). Thirty-eight palynomorphs were selected for the analysis. They were selected based upon abundance (total abundances greater than 50 grains, when su§i of all samples was considered), and pollen/spores with recognized paleoenvironmental significance. Samples with less than 50 grains were eliminated from this analysis because they probably do not represent a reliable representation of the palynoflora and only would introduce noise to the analysis. The non-metric multidimensional scaling (MDS) analysis produced the following groups (Fig. 6-8): Group A: Retimonocolpites regio, Bombacacidites annae, Psilamonocolpites grandis Group B: Proxapertites humbertoides, Retidiporites magdalenensis, Proxapertites cursus, P. operculatus Group C: Mauritiidites franciscoi Group D: Longapertites spp. Group E: Dinoflagellate cysts Group F: Spinizonocolpites "grandis", Retitricolpites magnus, Retistephanoporites "minutipori", Psilaperiporites "pauciporatus", Retitricolporites guianensis, Echitriporites trianguliformis, Psilatricolporites crassus, Polypodiisporites specious, Laevigatosporites

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113 MDS using Spearman's rank order coefficient, Stress: 0.17403; Kruskal/Iineardecrement=0, Dimension=2, Iterations=5, Minkowski constant 2, shepard plots 1 -1 -1.5 -\ 1 1 i 1 i I *\ t "\ ° £ Score " ~ ° ~ 1 axis Figure 6-8. Scattergram of species ordinations, from a non-metric multidimensional scaling (MDS) analysis using Spearman's rank-order coefficient. See discussion about the 7 groups identified. Species asignations are as follows: "Psilatriletes" sp. A=PSTA, "Psilatriletes" sp. B=PSTB, "Psilatriletes" sp. C=PSTC, Bombacacidites annae=BANNAE, Bombacacidites £revw=BBREVIS, Cicatricosisporiles dorogensis=CDORO, Clavatricolpites "densoclavatus"=CDENSO, Cyclusphaera "scabratus"=CSCABR, Echiperiporiles estelae=EESTELA, Echitriporites trianguliformis van "orbicularis"= ETRIANGU, Laevigatosporites h'ft«r=LTIBUI, Pediastrum-?ED\ AST, Perisyncolporites pokornyi=PPOKORN, Potypodiaceoisporilesl "fossuiatus"=PFOSSUL, Polypodiisporites specious=PSPEC\OS, Psilamonocolpites gram/is=PGRANDIS, Psilamonocolpites /ned//«=PMEDIUS, Psilaperiporites "pauciporatus" =PPAUCIP, Psilatricolporites cras5MS=PCRASSUS, Psilatricolporites w>acM/os/M=PMACULOS, Retibrevitricolporites "grandis"=RGRANDIS, Retidiporites magdalenensis=RMAGDALE, Retimonocolpites "ovatum"=ROVATUM, Retimonocolpites regio=RREGlO, Retisteplianoporites "minutipori"=RMlNUTIP, Retistephanoporiles angelicus=RANGEL, Retitricolpites magnus=RMAGNUS, Retitricolporites guianensis=RGUlANEN, Spinizonocolpiles "grandis"=SGRANDIS, Spirosyncolpites spiralis=SP\RAE, Striatricolpites catatumbus= SCATATUM, Verrutricolporites "reticulatus"=VRETI, Mauritiidites spp.=MAURIT, Proxapertites humbertoides and P. cursus=PROXA, Longapertites spp.=LONGA, Dinoflagellate cysts=DINOF, Proxapertites magnus=PMAGNVS, Proxapertites humbertoides=PHUMBE

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119 tibui, Clavatricolpites "densoclavatus", Cicatricosisporites dorogensis, Perisyncolporites pokornyi, "Psilatriletes" sp. C Group G: Bombacacidites brevis, Psilatricolporites maculosus, Echiperiporites estelae, Retibrevitricolporites "grandis", Striatricolpites catatumbus, Spirosyncolpites spiralis, Retistephanoporites angelicus, Cyclusphaera "scabratus". Discussion Fossil pollen assemblages can be used to identify diverse sedimentary environments, as has been shown for fluvial strata of the Bighorn Basin (Farley, 1990) and recent delta systems as in the Orinoco delta (Muller, 1959), and the Mississippi delta (Chmura, 1994). These assemblages generally differ in abundance of taxa rather than presence-absence (Farley, 1990). The interpretation of the MDS analysis was done based upon the spatial position of taxa along the first and second order axes, and on literature review (see Table 6-4). The axes indicate the coordinates of the n species in t dimensions that are calculated from a similarity matrix (Manly, 1994). The main goal was to identify fluvial plain-nearshore trends, if present. The environmental interpretations (fluvial, coastal) are used in a relative sense rather than in an absolute one. These terms only represent the position of a palynomorph assemblage relative to each other rather than an absolute position along the fluvial-nearshore gradient. Variations in the relative proportions of those groups through time are interpreted here to represent variations in major depositional systems that can be linked in a sequence stratigraphic context. The groups given by the MDS analysis can be divided in two large groups that are clearly separated along the axis 1: Groups A and B, and Groups E, F, and G (Fig. 6-8). Groups C and D are in intermediate value. These two large groups are separated due to different ages. Taxa present in A and B are typical elements of Paleocene floras such as Proxapertites, Bombacacidites annae, and Retidiporites magdalenensis (Germeraad et

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120 al, 1968). Taxa of groups E, F, and G are typical of Eocene deposits (e.g., Psilatricolporites crassus, Retitricolporites magnus, Perisyncolporites pokornyi). Taxa of groups C and D are common in both Paleocene and Eocene deposits (Muller et al, 1987). The grouping along the axis 2 seems to be due to a gradient fluvial to coastal environments that could be organized in the following manner. Group A seems to indicate Paleocene fluvial plain environments. Pollen of Bombacacidites annae is very similar to extant Bombax (Germeraad et al, 1968), a typical element of damp tropical forests (Graham and Jarzen, 1969). Group B indicates Paleocene coastal environments. Proxapertites cursus and P. operculums have a morphology similar to Nypa pollen and are concentrated in Paleogene deltaic and shallow marine sediments (Muller, 1979). Group C indicates pure stands of Mauritiidites. This pollen is very similar to extant Mauritia pollen, a palm that generally forms pure or mixed stands in permanently flooded and poorly drained soils in depressions in the flood or coastal plain (Muller, 1979; Lorente, 1986; Colinvaux, 1987; Hoorn, 1994; Rull, 1997a, b; 1998). This interpretation is also confirmed by the isolation of Mauritiidites in the ordination as also was found by the PCA analysis of Rull (1997a). Mauritia pollen has low dispersal capabilities and its presence in sediment is almost restricted where palm is growing (Rull, 1998). This has been shown in sediments from both coastal swamps (Muller, 1959), and inland fluvial valleys (Rull, 1998). It is rarely present in marine sediments (Muller 1959). The presence of Mauritiidites pollen indicates presence of Mauritia communities near the site of deposition (Rull, 1998). Group D is composed of a single taxon: Longapertites spp. (mainly L. proxapertitoides). Longapertites probably was produced by some type of palm (Muller, 1979) but its autoecology is uncertain. It could be suggested that it is produced by a palm that formed pure stands similar to Mauritiidites because it is also isolated in the ordination analysis (Fig. 6-8). Therefore, this group would represent stressful conditions

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121 in the floodplain or coastal plain perhaps in permanently or semipermanently flooded areas. Group G probably indicates Eocene fluvial deposits. Bombacacidites is a member of "Bombacaceae" (Germeraad et al, 1968, Muller et al, 1987), a small nonmonophyletic group of tropical trees that live in dense rain forest in South America and open savannas and weedy habitats in Africa (Heywood, 1985). "Bombacaceae" is nested within Malvacea, a monophyletic family (APG, 1988; Judd et al, 1999) Striatricolpites catatumbus, very similar to pollen of extant Leguminosae Crudia, was suggested as a fluvial plain element by Hoorn (1993). Crudia is a typical riverine forest element (Hoorn, 1993). Lorente (1986) associated Echiperiporites estelae to fresh water lakes and ponds in alluvial plain environments based on lithofacies and organic matter analysis. Graham (1993) associates it with coastal brackish-water associated with Rhizophora mangrove. This taxa, however, was not associated with any mangrove element in MDS analysis. Group F indicates Eocene coastal plain conditions. Spinizonocolpites is very similar to pollen of extant Nypa, a mangrove palm of southeast Asia, and has been found in coastal plain sediments in the Paleogene of Africa, South America, Europe, India, Borneo, and southeast United States (Germeraad etal, 1968; Muller, 1979; Jan du Chene, 1980; Westgate and Gee, 1990). This group also contains Psilatricolporites crassus, pollen very similar to extant Pelliciera rhizophorae that is a mangrove element distributed in the Pacific coast from Costa Rica to northern Ecuador. Psilatricolporites crassus has been found associated with coastal plain environments in South America and the Caribbean (Germeraad et al., 1968; Graham, 1977; Lorente, 1986; 1993). Echitriporites trianguliformis was tentatively suggested as part of coastal communities by Germeraad etal. (1968) and Colmenares and Teran (1993) for Paleogene deposits of Southwestern Venezuela. This suggestion is here supported by its close association in the ordination analysis with Spinizonocolpites and Psilatricolporites crassus. Rull (1997a) in

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122 his PCA analysis found Retritricolporites guianensis and Perisyncolporites pokornyi grouping together and interpreted the assemblage as indicative of coastal forest swamps. Here, these two taxa are grouping together again, and associated to P. crassus and Spinizonocolpites suggesting a coastal environment. However, Retritricolporites guianensis and Perisyncolporites pokornyi were also suggested as part of the riparian vegetation in Colombian Amazon during the Miocene (Hoorn, 1994). The same author states that abundant Perisyncolporites pokornyi was also found co-occurring with dinoflagellate cysts and Zonocostites ramonae (pollen of the extant mangrove, Rhizophora). This concurrence of P. pokornyi and Z. ramonae also was found by Lorente (1986) in Neogene deposits of Eastern Venezuela. Modern relatives of Polypodiisporites are spores of Poly podium (Polypodiaceae), that are widespread in the tropics. Some Polypodium species usually dominate fern fresh-water or slightly brackish swamps between the mangrove belt and Mflt/rm'a-dominated vegetation in the modern Orinoco delta (Rull 1997a). The ecological status of Cicatricosisporites dorogensis is uncertain. Modern relatives (Schizeae and Mohria) mostly inhabit dry, open, or semiopen habitats (Schizeae) or open forests, sandy soils or decaying logs (Mohria} (Germeraad etai, 1968; Kramer, 1990; Moran, 1998). Here, however, it is closely associated to Perisyncolporites pokornyi, suggesting a habitat related to coastal riverine conditions. Group E indicates nearmost neritic conditions. Most of fossil dinoflagellate cysts are from neritic origin (Evitt, 1985). Homotryblium and Polysphaeridium have been reported as a marginal marine taxon by Kothe (1990), Zevenboom et al. (Zevenboom et al, 1994), Brinkhuis (1994), Dale (1996), and Jaramillo and Oboh (1999). Several samples yielded very few or no palynomorphs. These types of samples could indicate normal oxidized floodplain conditions that are characterized by variegated mudstone and usually yield poor recovery of palynomorphs (Farley, 1990).

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123 The curves plotted in Figures 6-8, 6-9, 6-10, and 6-1 1 are the abundances of the each of the 7 groups (A-E) defined by the MDS analysis. The abundances for each of the curves were normalized to 300 grains for the samples that had counts greater than 300 grains. An additional curve consists of the abundance of reworked dinocysts. Higher abundances of reworked material may be expected during highstand and lowstand systems tracts because clast input from the continent is higher. The status of "reworked" for a dinocyst or pollen was establish on the following basis; (a) if it has not been reported for the Paleocene or Eocene (e.g., Dinogymnium, Odontochitina), and (b) if it has a Paleogene record but it became extinct before the latest Paleocene in northern South America (e.g., Buttinia andreevi). The last curve represents a relative paleoenvironmental curve. It is a weighted mean (Zn\ (i)/n) of the fluvial, coastal, and nearshore groups identified in the MDS analysis, where n represents the total number of taxa (abundance) in a particular sample and n] represents the abundance of each ecological group; (i) represents weighted categories whereby fluvial (groups A, G), coastal (groups B, F), and innermost neritic groups (group E) are weighted 1, 2 and 3 respectively. A particular sample can contain a palynomorph assemblage composed of pollen/spores that lived in the coastal plain, plus a set of sporomorphs transported from fluvial areas by rivers. The value produced by the weighted mean is called the palynomorph paleoenvironmental index (PPI) which combines all the information given by the palynomorphs of a sample into a meaningful value, that represents the average given by the whole assemblage. Plotting this value through the section can provide us with general trends in depositional environment changes (Figs. 6-9 to 6-11). The PPI curve for the Eocene interval (PPIe) was calculate using groups E (inner neritic), F (coastal), and G (fluvial), while PPI curve for the Paleocene (PPIp) was done using groups A (fluvial) and B (coastal). Samples that had less than 10 grains after including all groups were not used to calculate the PPI.

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126 Paleoecological groups Ma. Lon. fluvial coastal reworked B C D G F E RW 0 5 0 5 0 5 0 20 0 5 0 0 #grains 30 Environment from PPiEoc palynomorphs m i 2 3 _ _ 1100 1000 900 800 700 600 500 400 300200100 F: Fluvial CCoastal Figure 6-11. Paleoenvironmental interpretation of Uribe section based in abundance of 7 paleoecological groups derived from the MDS analysis (see text for discussion). PPIe:Palynomorph Paleoenvironmental Index for the Eocene (refer to Figure 6-8 for groups used in calculation of PPI indexes). Ma:Mauritiidites, Long-.Longapertites

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127 Lithology Previous Studies Each of the sections is located in a different area, Pinalerita in the Llanos foothills, Uribe in the Middle Magdalena Valley, and Regadera in the Catatumbo Basin (Figs. 3-1, 4-1). The stratigraphic nomenclature for each section is described here. In the Catatumbo area three formations comprises the Paleocene-Eocene: Cuervos, Mirador, and Carbonera Formations. The Cuervos Formation was named by Notestein et al. (1944) from Quebrada Los Cuervos in the Catatumbo area, 200km north of the Regadera section. The formation is composed mainly of claystones and shales, with abundant coal beds in its lower part and some evidence of marine influence; the upper part consists of gray and greenish-gray claystones with locally abundant red, yellow, and purple mottling (Notestein et al, 1944). Thickness range from 282 to 490 meters increasing northward. The contact with overlying Mirador Formation is sharp, and locally unconformable (Notestein et al, 1944). In the area of La Victoria creek, Germeraad et al. ( 1968) dated it as Paleocene (pollen zone of Retidiporites magdalenensis). In the Tibu anticline, Gonzalez (1967) dated the upper Cuervos as upper Paleocenelower Eocene based on pollen. Sutton (1946) reports a mollusc brackish to marine fauna of Ostrea sp., Anomial sp., and Diplodonta? from a black shale close to the base of the formation in Puerto Salado area. The Mirador Formation was named by F. de Loys in a 1918 private report (Porta, 1974), and then was redefined by Notestein et al. (1944). Type locality is from Cerro Mirador, upper Lora river, District of Colon (Venezuela), in the Maracaibo Basin, approximately 230km north of the Regadera section. It is divided into three units: a lower unit, 1 10-355m thick, predominantly composed of clean, massive, fine to coarsegrained sandstones and in part conglomerates. A middle shaly unit, 10-70m thick, and an upper unit, 40-75m thick, composed of sandstone, thinly bedded and less clean than the lower unit. The overall thickness of the formation ranges from 160 to 400m, thickening

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128 westward and northward (Notestein et al, 1944). The lower contact with Cuervos Formation is sharp, easily recognized, and locally an angular unconformity can be seen (Quebrada Aguacaliente and Gonzalez anticline) (Notestein et al, 1944). The time involved with this unconformity is uncertain. The top of the Mirador is where clean sandstones are overlaid by gray micaceous sandy shales of the Carbonera Formation. It is transitional in some areas (Rio de Oro) and reported as unconformable in some others in Venezuela (Notestein et al, 1944). In the area of La Victoria (Venezuela), Germeraad et al (1968) dated a correlative unit as lower to middle Eocene (pollen zones of R. triangulatus, P. crassus, and R. guianensis). In the Tibu anticline, Gonzalez (1967) dated it as lower to middle Eocene based on pollen. Germeraad et al (1968) stated that Gonzalez flora is "anomalous" because it contained Cicatricosisporites dorogensis rather low in the Mirador (pollen zone of Verrucatosporites usmensis), suggesting an upper Eocene age. Colmenares and Teran (1993) dated the formation as early to early middle Eocene using palynological data. The Carbonera Formation was named by Notestein et al. (1944) from Quebrada Carbonera in the Catatumbo area, 80km north of the Regadera section. It consists of a thick series of gray claystones, red and yellow mottled, with some gray arcillaceous sandstone intercalations, 5 to 30 meters thick. Coals are present in lower and upper parts of the formation. Glauconite and a mollusk fauna indicating brackish to marine conditions were found 100 meters below the top and 60 meters above the base of the formation. Thickness range from 410-500 to the south, to 720m to the east and north (Notestein et al, 1944). A brackish or semi-brackish Mollusca fauna described by Olsson in Notestein et al. (1944), 150 m below top the formation near Cucuta (30km north of Regadera section, 7km NE of Cucuta), yielded: Hannatoma n. sp., Cerithium sp., Harrisianella cf. peruviana Olsson, Turritella aff. chira Olsson, Melongena n. sp, Cymia cf. berryi Olsson, Polinices n. sp., Anomia n. sp., Rhaetomya sp., Ostrea sp., Pitar sp., dementia peruviana Olsson, Mactra sp., Tellina sp., Phacoides sp., Polinices (Neverita)

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129 cf. subreclusiana Olsson, Polinices sp., Turritella aff. chira Olsson, Area (Arginella) cf. puntabravoensis Olsson, Area {Arginella) cf. ocalis McNeil, Tagelus sp., Corbula sp. Olsson assigned a middle Oligocene to this assemblage. Durham (1949) added to the assemblage Area (Argina samanensis) Olsson?, Crommium palmarae Clark, Hannatoma emendorferi Olsson, and Cerithiella aff. C. heckscheri Olsson. Dusenbury (1949) collected in the Cerrito, near Cucuta, Pitar (Pitarella) colombiana Clark, Neverita bolivarensis Clark, Turritella aff. chira Olsson, Harrissianella peruviana Olsson, Cerithium (Perucerithium) cf. negritosense Woods, Hannatoma emendorferi Olsson. He also report another assemblage from Quebrada Seca, 9 km NE of Cucuta, that contains Area (Arginella) cf. puntabravoensis Olsson, Ostrea sp., Mactra sp., Pitar {Pitarella) colombiana Clark, Transennella bolivarensis Clark, dementia peruviana Olsson, Tagelus bolivarensis Clark, Macoma sp., Polinices sp., Crommium palmerae Clark, Turritella aff. chira Olsson, T. samanensis Olsson, Cerithiella sp., Harrisianella peruviana Olsson, Cerithium {Perucerithium) cf. negritosense Woods, Hannatoma emendorferi Olsson, Malanatria aff. acanthica Woods, Cornulina sp. 1, Cornulina sp. 2, Peruficus lagunitensis var. charanalensis Olsson, and Lyria? sp. Dusenbury (1949) and Durham (1949) re-analyzed the age of the fauna and concluded that the assemblage corresponds to upper Eocene mainly to the presence of Hannatoma emendorferi. However, these mollusc faunas are probably related to brackish-water facies making it less reliable for dating purposes. In the area of La Victoria creek (NW Venezuela), Germeraad etal. (1968) dated a correlative unit as upper Eocene (pollen zones of Verrucatosporites usmensis), in the area of Rubio road it was dated as middle to upper Eocene (upper Monoporites annulatus to V. usmensis zone). Colmenares and Teran (1993), based on palynology, dated this formation as middle middle Eocene to Oligocene in the Capacha and Delicias sections, Tachira state, near Cucuta. Unfortunately range charts were not provided

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130 In the Middle Magdalena Valley, the Tertiary sediments are distributed in two units, the Valley itself and the Nuevo Mundo syncline. The northern part of the Valley is bounded by the Mulatos/Cimitarra fault and Central cordillera to the west and the Chucuri flexion to the east (Julivert, 1961; Fabre, 1983). The Salinas fault separates the Nuevo Mundo syncline (where Uribe section is located) from the Valley (Julivert, 1961). Most of Tertiary sedimentation was controlled by syndepositional faults and folds, sediments increase in thickness toward the Salinas fault, and sedimentation is continue in synclines and major unconformities are found in anticlines (Porta, 1974). The stratigraphic nomenclature was a chaos in the first 30-40 years of exploration in the area. Similar names were used for different companies for different units, or different names for same unit. Here, the terminology suggested by Porta (1974) is followed. The Paleocene-Eocene stratigraphy comprises Lisama, La Paz, and Esmeraldas Formations (Porta, 1974). Lisama Formation was defined by Link in 1925 in a private report and then redefined by Wheeler (Wheeler, 1935). The type locality is located along Lisama creek. Another good exposure is located near Vanegas along Lebrija river, 15 km north from Uribe section (Porta, 1974). It consists of red, gray, brown, and gray shales, with massive muddy sandstone intercalations. Some coal beds are present. Environment is lacunar to deltaic. The thickness of the formation is 1225m in type section, although thickness is extremely variable (Porta, 1974). The lower contact is gradational with Umir Formation (Porta, 1974). The upper boundary is a regional unconformity with El Toro member of La Paz Formation (Porta, 1974). Van der Hammen (1956), Van der Hammen and Garcia (1966), and Germeraad et al. (1968) dated the formation as Paleocene (upper Foveotriletes margaritae , Ctenolophonidites lisamae, and lower Foveotricolporites perforates pollen zones of Germeraad et al, 1968). La Paz Formation was defined by geologist of the Tropical Oil Co. in Stutzer (1923), and then redefined by Wheeler (1935) and Morales etal. (1958). Type locality is

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131 near Vanegas town, along Lebrija river, 15 km north from Uribe section. It consists of gray massive to cross-bedded sandstones, sometimes conglomeratic, with minor intercalations of mudstones and shales mainly in the lower and middle part of the formation. In the lower part, there is a sandy mudstone unit named Miembro Toro, that has an average of 30m in the Mugrose anticline (west part of the basin), although it is extremely variable (Bueno, 1968). The thickness of the formation is 1000m in type section, although thickness is greatly variable (Porta, 1974). The lower contact is unconformable with Lisama Formation (Porta, 1974). The upper boundary is transitional with Esmeraldas Formation (Porta, 1974). Germeraad et al. (1968) dated the base of the formation as uppermost Paleocene to middle Eocene (upper Foveotricolporites perforates, Retibrevitricolpites triangulatus, and lower Retitricolporites guianensis pollen zones). The Esmeraldas Formation was defined by geologist of the Gulf Oil Co. in Wheeler (1935). Type locality is near Esmeraldas town, close to Sogamoso river, 35km south from Uribe section. It consists of thinly bedded sandstones and gray mudstones interbedded with gray shales occasionally red, purple or brown mottled. Some isolated coal beds are present. The upper part of the formation contains El Chorro fossiliferous horizon. The thickness of the formation is 1200m thickening north (Porta, 1974). The lower contact is gradational with La Paz Formation. The upper boundary is unconformable with the Mugrosa Formation (Porta, 1974), although Morales et al. (1958) stated that nature of contact is obscure. Pilsbry and Olsson (1935) dated the El Chorro fauna as upper Eocene based on the fresh to slightly brackish-water molluscan assemblage of Hemisinus (s. str.) corrosensis Pilsbry and Olsson, Potamides (s. lat.) macgilli Pilsbry and Olsson, Diplocyma wheeled Pilsbry and Olsson, D. sucionis Pilsbry and Olsson, and Sogamosa cyrenoides Pilsbry and Olsson (species names are according to the revised determinations of Olsson material by Nuttall, 1990). However, Nuttall (1990) in an extensive analysis of molluscan faunas of northern South America concludes

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132 that there is no molluscan paleontological evidence for the age of Los Chorros fauna to be more precise that "probably Paleogene". Pilsbry and Olsson (1935) based the late Eocene age determination in the inclusion of Tympanotomy lagunitensis (Woods) from the Saman Eocene of western Peru in their new genus Diplocyma. However, these species are barely similar warranting this inclusion (Nuttall, 1990). Van der Hammen (1958) dated it as upper Eocene based on palynological correlation of his "climatic cycles". Germeraad et al. (1968) dated the base of the formation as middle to upper Eocene (Retitricolporites guianensis to Verrucatosporites usmensis pollen zones). For the Llanos foothills, the Van der Hammen (1958) nomenclature is followed. He redefines Areniscas de El Morro, Arcillas de El Limbo, Areniscas de El Limbo, and San Fernando in a section along the Cravo river in the Llanos foothills. This stratigraphic nomenclature is followed to avoid the nomenclature often used by oil companies in the Llanos area. Their terminology does not correspond to the original sense of Barco, Cuervos, Mirador and Carbonera Formations as defined in the Catatumbo area (Cooper et al, 1995). The Areniscas de El Morro Formation was used for the first time in Van der Hammen (1957a), but formally defined by Van der Hammen (1958). Type locality is near El Morro, along Cravo Sur canyon, 100 km NNE of the Pinalerita section. The formation consists of white coarse to medium quartzsandstones, with some intercalation of shales with leaf remains in the middle part. Thickness is 250m in type locality. Palynological analysis of the middle unit indicates an upper Maastrichtian age according to Van der Hammen (1957a) although a species list in support of the age assignment was not provided. The Arcillas de El Limbo Formation was defined by Hubach in 1941 (in a Shell internal report, according to Van der Hammen, 1958). The type locality is near El Limbo, 2km NW of El Morro, Cravo Sur River, 100km NNE of the Pinalerita section. The formation consists predominantly of gray claystones, some coal beds. Some

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133 sandstones are present in the lower part. The thickness is 250m in the type locality. Lower contact is conformable with the Areniscas de El Morro Formation. Upper contact is conformable with Areniscas de El Limbo (Van der Hammen, 1958). The formation is dated as Paleocene by Van der Hammen ( 1958), although no data is provided. Cazier et al. (1995) and Cooper et al. (1995) described a 212m section in the Cusiana field, east of Guaicaramo fault, an area 70km north-northeast of Pinalerita section. They described the section as composed of two intervals. The lower interval (82m thick) is composed of estuarine mouth sand and mud, tidally-influenced estuarine fill, channel-fill sandstones, and muddy bioturbated estuarine deposits. They called this interval "Barco" Formation. The upper interval (132m) is composed of muddy, lower coastal plain deposits that they called "Cuervos" Formation. Although no paleontological evidence is provided, they dated Barco as late Paleocene (Cazier et al, 1995) and Cuervos as early Eocene (Cazier et al, 1995) or late Paleocene (Cooper et al, 1995). Is this "Barco" correlated with the upper segment of Areniscas de El Mono or is it correlated with lower Arcillas de El Limbo?. Although these two areas, Morro and Cusiana, are very close to each other (40km apart), they are separated by Guaicaramo fault, a major fault that has had significant lateral and orthogonal transport (Dengo and Covey, 1993; Montes personal communication). In Cusiana, "Barco" is marginal marine and 82m thick and "Cuervos" is coastal plain and 132m thick. In El Morro, on the other hand, the upper portion of Areniscas de El Morro is fluvial and approximately 120m thick, and the Arcillas de El Limbo are coastal plain and 250m thick. These data indicate how complex the geology of the area is, especially because strata along the hanging wall of the Guaicaramo fault have had significant horizontal displacement that has put in close contact facies that originally were separated by tens of kilometers. This could produce large thickness, facies, and age changes in small area. Also, clearly the lack of published data supporting age assignments has created an enormous confusion when correlating formations.

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134 Guerrero and Sarmiento (1996) propose to use the stratigraphical terminology of the Boyaca region in eastern Cordillera for the Llanos foothills. They correlate the Socha Inferior Formation (dated as late Paleocene based on pollen and spores) with the upper segment (~120m) of Areniscas de El Morro. However, I do not follow their suggestion because of the following reasons: The age for the upper portion of Areniscas de El Morro is unknown, Socha inferior has not been very well dated in the type section at Chicamocha (Sarmiento and Alvarado, 1944 in Porta, 1974), the Paleogene sequence in Boyaca contains the oolitic ironstone of the Concentration Formation, that is not present in the Llanos foothills. It could be argued that underlying formations (Socha Inferior and Socha Superior) do not have lithological continuity in the Llanos Foothills as well. Finally, Guerrero's approach could lead to an oversimplification of the geology of the area. The Areniscas de El Limbo Formation was defined by Hubach in 1941 (in a Shell internal report, according to Van der Hammen, 1958). The type locality in near El Limbo, 2km NW of El Morro, Cravo Sur River, 100km NE of the Pinalerita section. The formation consists predominantly of conglomeratic sandstones with a middle shaly unit. The thickness is 270m in the type locality. Lower contact is conformable with Arcillas de El Limbo Formation. Upper contact is conformable with San Fernando Formation (Van der Hammen, 1958). Formation was dated as lower to middle Eocene by Van der Hammen (1958), although no data was provided. Cazier et al. (1995) and Cooper et al. (1995) described a 131m section in the Cusiana field, east of Guaicaramo fault, an area 70km north-northeast of Pinalerita section. They described it as composed of three intervals, the lower unit composed of medium-coarse, mature, quartz sandstone of estuarine channel-fill deposits. The middle unit is composed of muddy marine, interdistributary bay, and nonmarine floodplain deposits. The upper unit contains estuarine and distributary channels sandstones and minor mudstones. They named this formation "Mirador", and dated it upper Eocene, although no data was provided in

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135 support of this conclusion. They stated that their use of Mirador does not correspond to the original term defined in Maracaibo Basin. San Fernando Formation was defined by Hubach in 1941 (in a Shell internal report, according to Van der Hammen, 1958). The type locality is in the north part of La Macarena range in the Hernandez plateau, 180km SW of the Pinalerita section. Van der Hammen, however, describe the section from El Limbo, 2km NW of El Morro, Cravo Sur River, 100km NE of the Pinalerita section. The formation consists predominantly of mudstones. Paba-Silva and Van der Hammen (1958) dated it as upper Eocene-lower Oligocene based on palynology although no supporting data was presented. Hopping (1967) and later Germeraad et al. (1968) also uses the term San Fernando Formation in some areas of the Llanos area. They used in the stratigraphy of two wells: Voragine1 and Chafurray-3. It consists of a brackish, coastal plain muddy unit. It is overlaid by Orteguaza Formation but its lower contact is unknown. Germeraad et al. (1968) dated this unit as Late Eocene to early Oligocene (upper Verrucatosporites usmensis to lower Cicatricosisporites dorogenis pollen zones). Germeraad et al. (1968) also used the term for a lithological section in the Cobugon river near the Venezuela frontier. It is unclear if this section corresponds to the same unit as defined in the type section (320 km apart). Porta (1974) recommended to limit the term to the type section area and closely localities. I used the term following Van der Hammen (1958) and its description in the Morro. Cazier et al. (1995) and Cooper et al. (1995) described a 1.3km section in the Cusiana field, east of Guaicaramo fault, an area 70km north-northeast of Pinalerita section. They described the formation as composed of several (four) intervals composed of a muddy unit capped by a sandstone, accumulated mainly in coastal plain. They called it "Carbonera" Formation, and dated it as uppermost Eocene to early Miocene (no data provided). This "Carbonera" does not correspond, however, to the original term defined in Maracaibo Basin (Cooper et al, 1995).

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136 In order to produce a paleobathymetric curve that can be used in the sequence stratigraphic analysis of each section, lithological characteristic must be used to interpret environments of accumulation. Here, the ideal facies models of Galloway and Hobday (1996) were used in order to interpret the gross depositional systems for each studied sections. The purpose of the lithological analysis was to interpret the overall trend in gross depositional environments that could be related to changes in base level and therefore placed in a sequence stratigraphy framework. Major clastic environments that could be represented in the studied section were classified according to Galloway and Hobday (1996) in 3 major environments: fluvial, deltaic and estuarine (Figs. 6-12, 6-13. 6-14). Fluvial environments were divided in bedload channel, mixed-load channel, and suspension-load channel environments. Delta systems were divided into delta plain, delta front (tide, wave, or fluvial dominated), and prodelta. Estuaries were divided into shoreface and beach, barrier islands/tidal deltas, and tidal flat/tidal channels/estuary fills/lagoon environments. A brief description of each environment is shown in Figures 6-12, 6-13, and 6-14 along with the major lithologic characteristics that were used to infer the environments of accumulation for the sections studied. Results Description of the lithology and interpretation of the sedimentary environments are shown in Appendices B, C, and D, and Figures 6-15, 6-16, 6-17. Pihalerita section . The Pinalerita section is divided into several intervals described below from bottom to top (Appendix B, Fig. 6-15). Interval -2 to Om, top Arenisca de El Morro Formation. This interval is characterized by white fine to medium-grained, well sorted, quartz-sandstones, with planar and trough-cross bedding, and no evidence of bioturbation. These deposits

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137 FLUVIAL ENVIRONMENTS fluvial plain | — coastal plain bed-load channels Braided channels avalanche or planar x-b trough x-b sand-gravel Chute channels trough, planar x-b avalanche x-b trough x-b sand-gravel Backswamp/interchannel lakes peat, fine grained Point bars levee planar x-b, ripple climbing ripples, planar 1. trough x-b Abandoned channel plugs fine-scale Overbank deposits Levee ripple, climbing ripple, wavy, and planar lamination Crevasse splay trough x-b., ripple. &g*ij^ g£ climbing ripple, wavy, and planar lamination Abandoned channel plugs fine-scale lamination, root mottling Flood plain lamination, root mottling Pointbars 3 mud-plug npplc and parallel root mottling lamination trough x-b lag Figure 6-12. Schematic representation of the major divisions of fluvial environment used in the lithological interpretation (adapted from Galloway and Hobday, 1996).

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138 DELTA ENVIRONMENTS delta plain Distributary channel-fills jmud-plug ripple and parallel lamination mm rough x-b lag Backswamp/ lakes peat, fine grained Overbank deposits Levee ripple, climbing ripple, wavy, and planar lamination Crevasse splay trough x-b., ripple, = l' m b' n S npple, ^^avy, and planar lamination Floodplain peat, fine grained prodelta m massive 3 to poorly laminated, slumps Fluvial-dominated Distributary mouth bars planar lamination trough x-b slumps prodelta muds Distributary channel fills 3_mud-plug ripple and parallel lamination trough x-b lag Overbank deposits Levee ripple, climbing ripple, wavy, and planar lamination Crevasse splay trough x-b., ripple, climbing ripple, wavy, and planar lamination Interdistributary bays r.jg:. muddy, bioturbated Wave-dominated Beach ridge sands low angle planar lamination trough x-b ripples Tide-dominated Estuary distributary channels rough, planar, llel, ripple amination, mud rapes Tidal sand ridges trough, parallel, planar lamination ripples Figure 6-13. Schematic representation of the major divisions of delta environment used in the lithological interpretation (adapted from Galloway and Hobday, 1996).

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139 ESTUARINE ENVIRONMENTS Tidal flats flaser, wavy, lenticular, and ripple lamination trough, parallel, planar lamination Lagoons mm muddy, bioturbated or laminated Figure 6-14. Schematic representation of the major divisions of estuary environment used in the lithological interpretation (adapted from Galloway and Hobday, 1996)

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140 m. Pinalerita in Environment from pal>Tiomorrjhs Environment from palynofacies F UC LC Lithology sequence Paleobathymetry stratigraphy BL MI, AM LSL LSL-E LSL toE BL USL BL ML USL ML USL LSL toE USL BL F: Fluvial C:Coastal M: Innermost Neritic FFIuvial UC: upper coastal plain LCLower coastal plainInner Self 750 700 650 600 500 450 400 350 250 200 150 100 HST -MFSH TST ~TS— LSI' -SBHST -MPS-" TST -TSLST SL BL. Fluvial plain (bed-lead) Ml j Fluvial to Coastal plain (Mixed-lead) uSL: Upper Coastal plain (Suspended-load) ISL'Lower Coastal plain (Suspended-load) EEstuarine I:innennost shelf Figure 6-15. Sequence stratigraphic interpretation for Pinalerita section based in lithofacies interpretation, paleonvironment from palynofacies, and paleoecology. Key for lithological symbols in Appendix B.

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Figure 6-16 Sequence stratigraphic interpretation for Regadera section based in lithofacies interpretation, paleonvironment from palynofacies, and paleoecology. Key for symbols in Appendix C, and Figure 6-15.

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Figure 6-17 Sequence stratigrphic interpretation for Uribe section based in lithofacies interpretation, paleonvironment from palynofacies, and paleoecology. Key for symbols in Appendix D and Figure 6-15.

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143 indicate high energy flows suggesting braided or chute channels-fills in bed-load channels environments of the fluvial plain. Interval 0-1 17m, lower Arcillas de El Limbo Formation. It is characterized by dark green to gray mudstones, generally light green to silty red to light gray mottled, sometimes burrows are evident. These fine units are interbedded with three sandstones units (510m thick) characterized by slightly upward fining grain patterns of coarse to medium lithic to quartzsandstones with planar and trough cross bedding, planar lamination, muddy intraclasts, bioturbated at the base of the channels. These characteristics suggest deposition in estuary distributary channel-fills and tidal sand bars in small bay head deltas in the estuary zone. The base of each sand body seems to indicate a flooding event on the coastal plain (bay head abruptly overlying coastal plain deposits) and here is interpreted as the base of a parasequence. In general this first interval corresponds to lower coastal plain to estuarine environments (Figs. 6-14, 6-16) according to the facies model described above (after Galloway and Hobday, 1996). Interval 1 17m to 186m, lower Arcillas de El Limbo Formation. This segment is divided into two units: 1 17162m, and 162186m. The first unit (1 17162m) is characterized by green to gray mudstones, with scatter plant remains, and occasionally plane-parallel lamination. Thinly bedded intercalations of muddy sandstone with ripple lamination are present. Toward the upper part of the segment there is an increase in purple to gray claystones. This unit suggests suspension-dominated channel environments of the coastal plain. The second unit (162186m) is dominated by finingupward lenticular beds of medium to fine sandstones with trough and planar crossbedding, plane-parallel and ripple lamination, capped by coals and thinly bedded muddy sandstones. This lithology suggests point bars, levees and floodplain subenvironments of a mixed-load channel system in the fluvial to lower coastal plain (Figs. 6-12, 6-16). This unit corresponds to a parasequence.

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144 Interval 186m to 399m, upper Arcillas de El Limbo Formation. This segment is divided into three units: 186-3 18m, 318-381m, and 381 -399m. The first unit (186-3 18m) is dominated by dark to light gray claystones with scattered sandy pellets, interbedded with thinly bedded fine sandstones with ripples and trough cross-bedding. Mottled green to purple claystones are more common toward the top of the unit. This lithology suggests suspended-load channels in the upper Coastal Plain environment. Next unit (318-381m) is dominated by medium to fine-grained lithic sandstones with planar and trough crossbedding and ripple marks, interbedded with light green claystones. This suggests mixedload channels in the fluvial to lower coastal plain environment. The next unit (381399m) is dominated by very coarse to coarse lithic sandstone, massive, with large-scale trough and planar cross-bedding, and conglomeratic lenses with chert and quartz fragments. This lithology suggests high-energy deposition as in braided or chute channel-fills in bed-load channels of the fluvial plain environment. These three units constitute a single prograding cycle (parasequence). Interval 399-477m, upper Arcillas de El Limbo Formation. It is dominated by green to purple claystones, intensely red-mottled, interbedded with a few, thinly bedded siltstones. This lithology suggests suspension-load channels of the upper coastal plain environment. Interval 477-643m, lower Areniscas de El Limbo Formation (meters 0 to 166 of formation). Ii is dominated by well sorted, coarse, thick bedded, mature, massive, white to yellow quartz sandstone, with conglomeratic intervals and large scale trough and planar cross bedding. This lithology indicates high energy deposition in bed-load dominated channels in the fluvial environment. Interval 643-7 14.6m, upper Areniscas de El Limbo Formation (meters 166 to 237.6). It is subdivided into three units. First unit, 643-689m (meters 166 to 212), is characterized by coarsening-upward, massive, medium to fine quartz sandstone beds with intense bioturbation {Thalassinoides among others), interbedded with bioturbated dark

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145 gray mudstones. This lithological assemblage suggests small bayhead deltas in estuarine environments. Second unit, 689-699.5 (meters 212 to 222.5), is dominated by a gray mudstone with plane-parallel lamination suggesting floodplain to coastal lakes in suspended-load channels in lower coastal plain environment. Third unit, 699.5-714.6 (meters 222.5 to 237.6), is characterized by black mudstone with flaser lamination, leaf remains, Thalassinoides, fine sands, thinly bedded with trough cross bedding and ripples marks. This lithological assemblage suggests tidal flats in an estuarine environment. Units 1 and 2 form a prograding unit (parasequence). Interval 7 14. 6-786. 6m lower San Fernando Formation (meters 0 to 72). It is subdivided into three units. First unit, 714.6-721 (meters 0 to 6.4 of San Fernando Formation), is a black mudstone. Second unit, 721-743 (meters 6.4 to 22), is dominated by green to gray claystone with scattered thin-bedded siltstone beds, and possible a thin layer of phosphorite. This lithology suggests suspension-load dominated channels in lower coastal plain to estuarine conditions. Third unit, 723-786.6 (meters 22 to 72) is characterized by a monotonous lithology of green claystones suggesting suspension-load dominated channels in lower coastal plain environments. Regadera section . Regadera section is divided into three intervals described below from the bottom to the top (Appendix C, Fig. 6-16). Interval -70m to 0m, upper Carbonera Formation. This interval is characterized by light gray to purple mudstone, with red to green mottling, interbedded with thinbedded green fine-grained lithic quartzarenite with ripple lamination, and very finegrained massive green lithic arenite and purple siltstones. This lithology suggests floodplain and overbank deposits of suspension-load dominated channels in the coastal plain environment. Interval 0-82m, lower Mirador Formation. This interval is dominated by thickbedded, white quartzarenite, fairly sorted, with large scale planar, trough cross-bedding to

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146 massive, and planar lamination, conglomeratic beds, intraclasts, interbedded with fine to very fine-grained lithic quartzarenite, dark gray to green with plane-parallel lamination. This lithology suggests high energy environments as braided/chute channels in bed-load dominated channels of the fluvial plain environment. Two parasequences could be recognized (0 to 28m, and 28 to 82m) that indicate a net progradation of the system (more coarser-grained channel-fills toward top of parasequence) and are overlaid by a minor transgression but within the bed-load environment (Fig. 6-16). Interval 82-285. 5m, upper Mirador Formation. This interval is dominated by thin-bedded fine gray lithic quartzarenite with ripple and discontinuous lamination interbedded with claystones, and dark gray upward-finning medium to fine arenites, with gravel lags, trough and planar cross-bedding capped by ripple and plane-parallel lamination. Scattered thin coal layers are present as well as light gray claystones with some mottling (bioturbation?), and isolated lenticular bodies of very fine-grained gray arenite with ripple lamination. This lithological assemblage suggests point bars, overbank and floodplain deposits of mixed-load channels in the fluvial environment. Three parasequences could be recognized (82 to 165m, 165 to 21 lm, and 21 1 to 285.5m). They indicate a net progradation of systems (fine to the base, and more sandy to the top of the parasequence). First and second parasequence (82 to 165m, 165 to 21 1) are overlaid by a minor flooding within mixed-load system, the third is overlaid by a major flooding (at 285.5m). Interval 285. 5-307. 5m, lower Carbonera Formation. It is characterized by thinly bedded fine-grained lithic quartzarenites, with lenticular lamination, and abundant burrow trails. This lithology suggests overbank deposits in areas with marine influence in lower coastal plain to estuarine? environments. Uribe section . Uribe section is divided into 4 intervals described below from bottom to top (Appendix D, Fig. 6-16).

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147 Interval -14 to Om, upper Lisama Formation. This interval is dominated by purple claystone, red mottled, that suggest floodplain sediments of suspended-load dominated channels in the upper coastal plain. Interval 0-1 80m, lowermost La Paz Formation. It is characterized by clastsupported polymictic conglomerates, massive coarse-grained lithic arenites, thick bedded, and large scale planar and trough cross-bedding that indicates high energy deposition in braided/chute channels in bed-load channels of the fluvial plain environment. Two prograding units (parasequences) could be recognized: 0 to 84m, and 84 to 180m. Both are within bed-load environment, and have purple to red claystones toward base and coarser material toward the upper part of parasequence. Interval 180-585m, lower La Paz Formation. This interval is divided into three units: 180 to 255m, 255 to 466m, and 466 to 585m. The first unit (180-255) is dominated by fine to medium-grained lithic arenites, thin-bedded, with plane-parallel lamination interbedded with red claystones, and thin coal beds. The second unit (255-466) is characterized by medium lithic arenites with trough cross-bedding interbedded with black shales and thin-bedded, very fine-grained lithic arenites and several covered intervals that probably are fine-grained because they produced valleys in topography. The unit has toward the top thin to medium-bedded, medium to coarse-grained lithic arenites with planar cross-bedding, and isolated lenticular arenite bodies in dark shales. The third unit (466-585) is dominated by red to brown claystones in the lower part, and fine-grained lenticular quartzarenites, thin-bedded and amalgamated that are interbedded with fine quartzarenites with lenticular lamination and upward-fining channel-fills with gravel lags, and trough and planar cross-bedding. These three units indicate floodplain, overbank deposits, and point bars in mixed-load dominated channels of the fluvial environment. Each unit represent a net progradation (parasequence) with fine grained facies in the lower part and coarser facies toward the upper part of the unit.

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148 Interval 585-989m, upper La Paz Formation. Most of this interval is not exposed or is poorly exposed. The first 134m (585-719) are poorly exposed and dominated by light gray claystones interbedded with thin-bedded, medium-grained lithic arenites. This lithology suggest mixed-load dominated channels of the fluvial environment. The upper 270m (719-989) are dominated by coarse to medium-grained quartzarenites, with large scale trough and planar cross-bedding, and conglomeratic beds with scarce presence of fine sediments. This lithology indicates bed-load dominated channels of the fluvial environment. The whole interval constitutes a parasequence. Interval 9891046m, uppermost La Paz Formation. Lower part of this interval is covered and probably is Fine-grained sediment (gives a topographic low), toward the top outcrops a massive, medium-grained quartzarenite, in amalgamated lenticular bodies. This lithology suggests mixed-load environments of the fluvial plain. Interval 10461066m lowermost Esmeraldas Formation. It is dominated by purple mottled light gray claystones suggesting floodplains in suspended-load dominated channels of the upper coastal plain environment. Sequence Stratigraphy Interpretation Previous Studies Sequence stratigraphy is relatively new field in Colombian geology. Very few studies has been published on sequence stratigraphy of Paleocene-Eocene strata in Colombia. Most of the sequence stratigraphic analysis are produced by oil companies and remain unpublished or are only presented as abstracts for symposia (e.g., Middle Magdalena area: Ramon and Cross, 1996; 1997; Suarez, 1997a; 1997b; Villamil and Restrepo-Pace, 1998; Llanos foothills: Pulham, 1995; Fajardo and Cross, 1996; Pulham etai, 1996; Pulham etal., 1997; Llanos: Malagon, 1997; Aurisano, 1998). Four papers have addressed sequence stratigraphy interpretations for Paleocene-Eocene strata in Colombia: Cooper et al. (1995), Cazier et al. (1995), Guerrero and Sarmiento (1996), and

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149 Vergara and Rodriguez (1997). The first three papers are results from exploration by the British Petroleum Company in the recently discovered giant oil field of Cusiana in Colombian Llanos foothills. The following is a brief summary of the sequence stratigraphy presented by Cooper et al. (1995) with additional data from Cazier et al. (1995, 1997). Cooper divides Paleocene-Eocene strata in three sequences (T10, T20, and T 30) grouped in two PreAndean Foreland Basin megasequences (Fig. 6-18). The first megasequence includes sequences T10 and T20. This megasequence starts with the development of the PreAndean Foreland Basin produced by the accretion of the western cordillera that ended the back-arc Cretaceous marine deposition (Dengo and Covey, 1993). This orogenesis was active in maintaining a topographic high and sediment source in the Central and Western Cordilleras for the foreland basin developed east of Central Cordillera during most of the Mesozoic (Dengo and Covey, 1993). The depositional axis of this foreland basin was initially the Middle and upper Magdalena valleys, migrating with time toward the east to the actual position along the western margin of Llanos area (Villamil and Restrepo, 1998). The T10 sequence (Fig. 6-18) is dominated in the Eastern Cordillera by coastal and alluvial-plain deposits of the Guaduas Formation that is dated as late Maastrichtian to early Paleocene (Sarmiento, 1992). This sequence is not present in the Llanos area or the Llanos foothills east of the Guaicaramo fault being correlative with a hiatus in those areas spanning the Cretaceous-Tertiary boundary. The T10 sequence shows a general northward and eastward thinning. T10 is present west of Guaicaramo fault suggesting some degree of fault control on T10 deposition by differential subsidence across the fault. In the Middle Magdalena, T 10 is represented by shales and sands (Lisama Formation). Next sequence is late Paleocene T20 (Fig. 6-18). Transgression and loading of protoforeland basin due to deformation in Central and Western Cordilleras reinstalled deposition on Llanos foothills and across Llanos area during this sequence. Barco

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150 if > s. ^Sequence Cj ^ stratigraphy UJ 3 § U U s O uj u u w Cu Cu Ou & P 3 UJ Z UJ u o UJ -J £ OS UJ a. a, P HST — MFSTST -TS— LST HST — MFSTST -TSLST -SBFigure 6-18. Cooper et al. (1995) and Cazier el al. (1995) sequence stratigraphic model for Paleocene-Eocene Colombian sedimentary strata

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151 Formation forms a basal transgressive systems tract (TST). It is a sand-rich, estuarine, Guyana shield-derived deposit. Basal T20 is present in Llanos foothills, Eastern Cordillera (part of Socha Formation), and Middle Magdalena Valley. In the Llanos foothills this basal T20 is called Barco Formation. It includes from the base, muddy bioturbated estuarine deposits, overlain by tidally-influenced estuarine channel-fill sandstones, followed by progradational estuary mouth sandstones and mudstones (Cazier et ai, 1995). This succession, approximately 82m thick, suggest TST and HST filling one or more incised valleys that intergrades transitionally with the overlying Cuervos Formation (Cazier et ai, 1995). Following the transgressive systems tract (TST) of T20, a highstand systems tract (HST) developed and shoreline migrated westward producing an extensive regression in Eastern Cordillera and Llanos foothills (Cuervos, Bogota, and Picacho Formations). In the Llanos foothills this HST constitutes the Cuervos Formation, a muddy section accumulated in lower coastal plain environments, approximately 132m thick (Cazier et ai, 1995) and dated as upper Paleocene (Cooper et ai, 1995) or lower Eocene (Cazier et ai, 1995) in the Cusiana field. A major drop in relative sea level occurred at top of T20 (54 my-earliest Eocene) resulting in a shift of deposition to the west and north and a major sequence boundary. In the Llanos it resulted in a disconformity (without angular component) that encompass 16 my (early-middle Eocene). It also produced thrusts and folds in upper Magdalena Valley. Earliest middle Eocene sediments are absent in Colombia due to deformation that Cooper relates to change in direction and rate of subduction of Nazca Plate (Pardo-Casas and Molnar, 1987; Daly, 1989). Between anomalies 21-18 (early to late middle Eocene), the Nazca-South American convergence increased to 164 +/65 mm/a at the latitude of Peru and 204+/80mm at latitude of Ecuador (up from 55 +/28 mm/a during anomalies 30-3 1 to 21: Maastrichtian to latest early Eocene) and perhaps a few millions years before and after this interval (Pardo-Casas and Molnar, 1987; Daly, 1989). Between anomalies 30-

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152 21 (Maastrichtian to latest early Eocene) the Nazca plate seems to have rotated about a pole in southern South America so that it converged with northern South America. By the beginning of anomaly 2 1 , the Nazca plate started to converge less obliquely with the South American plate (Pardo-Casas and Molnar, 1987). There is a correlation of this rapid convergence with the late Eocene Incaic phase of intense tectonic activity in Peru (Pardo-Casas and Molnar, 1987) and the formation of a major pull-part basin in Ecuador forearc (Daly, 1989). However, rapid convergence alone is not a sufficient condition for Andean margins to be built, a young ocean floor is also necessary. Unfortunately, age of ocean floor subducted beneath South America before 25 Ma is still unknown (PardoCasas and Molnar, 1987). The late Pre-Andean Foreland Basin started with "sequence" T30. For this interval, Cooper is using Galloway's concept of sequence (a genetic stratigraphic unit bounded by maximum flooding surfaces, Galloway, 1989), instead of sequence concept (bounded by sequence boundaries, Van Wagoner et al 1990) that Cooper used for T 10 and T20. Deposition in the Llanos started again in the latest middle Eocene (-40.5 my) due to a regional transgression that spread southward and eastward from the foreland basin. T30 onlapped much farther east on Guyana shield than T20. Initial T30 in the Llanos Foothills (Mirador Formation) is dated as ~38my (late middle Eocene) and consisted of mature quartz-arenites of fluvial and estuarine valley-fill deposits contained in muddier coastal plain deposits (Cazier et al, 1995). Mirador in Cusiana area is ~ 131m thick. It is divided in three subunits. The lower subunit is a medium to coarse sandstone deposited in estuarine channel fills of a number of valleys that incised in an aggrading coastal plain (Cazier et al, 1995). These strata contain brackish ichnofacies as Ophiomorpha, Planolites, Teichichnus, Thalassinoides, Diplocraterion, Paleophycus, Macaronichus, Gyrolithes, Planolites, and Arenicolites (Cazier et al, 1995, 1997). This lower Mirador unit is succeeded by a muddy marine interdistributary bay and nonmarine floodplain deposits that form a middle shale unit in Cusiana, and in the Llanos area

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153 (Cazier et al, 1995). This muddy unit is overlain by the upper Mirador, a succession of intensely bioturbated coarser grained estuarine and distributary channel sandstones, and minor mudstones that become more marine until marine flooding at -34 my (latest late Eocene) that ended T30 "sequence" (Cazier et al, 1995). This marine flooding is identified by dinoflagellate cysts such as Spiniferites, Polysphaeridium, Operculodinium, Cordosphaeridium, Homotryblium^ Cribroperidinium, and Hystrichokolpoma (Cazier et al, 1997). On the Llanos, it is dominated by fluvial and alluvial fan coarse sandstones ranging from 152 to 61m thick (Mirador Formation), although in the area of Cano Limon (northeastern Llanos) it has been interpreted as a 80m thick, series of medium to coarse sandstones accumulated in a mainly river-dominated delta system, with several marine shales, delta fringe sands, and probably wave-dominated deltas, 80m thick (Cleveland and Molina, 1990; McCollough and Carver, 1992), and dated as early to late Eocene (Cleveland and Molina, 1990, Fig. 12-7, p. 289) although supporting data is not provided. T30 deposits are called Gualanday, La Paz, and Esmeraldas Formations in Magdalena Valleys and occur over a dramatic angular unconformity, although has been reported only in subsurface anticlines the west side of the Valley (Julivert, 1961). T30 thickness is extremely variable due to fault control or by westward thickening into foreland basin. T30 ended with a maximum flooding surface(MFS) at -34 my-latest late Eocene. After T30, four major cycles (T40-T70) of lower coastal plain sediments, marineinfluenced, accumulated in Llanos area and Llanos foothills (Cazier et al., 1995). Each "sequence" is composed of a muddy HST, a thin forced regression (LST), and a sandy TST. These are called Carbonera Formation in the Llanos area (approximately 1 .3km thick), upper Esmeraldas, Mugrosa, Colorado, and La Cira in Middle Magdalena Valley, and Concentracion in the Eastern Cordillera. Upper T70 is dated as 16.5 my (early Miocene). This "sequences" record easterly migration of foreland basin subsidence that culminated with onset of Eastern Cordillera deformation. T30-T70 sources are Guyana shield, and parasequences were prograding westward into basin. T40-T70 cycles were

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154 produced while Nazca-South America convergence was slower (anomalies 13 to 7, rate: 50+/-30mm/y at the latitude of Peru; 44+/-26 mm/y at the latitude of Ecuador) and probably tectonic activity was also relatively quiescent (Pardo-Casas and Molnar, 1987; Daly, 1989). However, it seems contradictory that quiescent times during T40-T70 produced fine sediments instead of coarse sediments as low generation of accommodation space would predict (Posamentier and Allen, 1993). The same argument could be used for T30 deposition, that was a period of fast convergence that probably would increase the generation of accommodation space and, however, extensive arenites are deposited. Higgs (1997) challenged some of the interpretations of Cooper et al. (1995). He disagreed in the marine influenced interpretation for environments of Barco (lower T20) and Mirador (T30) Formations. According to Higgs (1997) data presented by Cooper does not fully support the estuarine interpretation, and ichnofossils interpreted as indicating marine influence can also be found in fluvial deposits. Also, Higgs did not find any evidence of marine influenced deposits in correlative formations in western Venezuela, which according to paleogeographic interpretations of Cooper should be found. However, as Cazier et al. (1997) pointed out, published biostratigraphic data from southwest Venezuela, Colombian Llanos foothills, Eastern Cordillera, Middle Magdalena Valley and the Llanos areas is very scarce, making correlations based on formational names very uncertain. Probably the Mirador Formation in Llanos foothills is not lateral equivalent of either Mirador or Guafita Formation in southwestern Venezuela (Cazier et al, 1997) and it is possibly younger (McCollough and Carver, 1992). A clear picture of either sequence stratigraphy or paleogeography of Paleocene-Eocene deposits is still elusive, although the conceptual model presented by Cooper et al. (1995), and Cazier et al. (1995) and (1997) are appropriated working hypothesis upon which improved interpretations can be done as more data is added, especially biostratigraphic. Guerrero and Sarmiento (1996) and Vergara and Rodriguez (1997) only addressed Paleocene strata (Fig. 6-19). Guerrero and Sarmiento (1996) propose a sequence ST2,

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155 Guadualera section Guerrero and Sarmiento, 1996 LOWER EOCENE ^ ^"Sequence O 0 stratigraphy UJ 5 U 2 U UJ Cu Cu P UJ z uj u o m UJ o u o uj — < z u o UJ u UJ Du Cu P UJ z UJ u o UJ -J £ a UJ cu Cu 3 HST — MFSTST -SBHST — MFSTST -TSLST -SBCarbonera Mirador Cuervos Barco 250 m. 200 150 100 50 TST I — TSLST -SBSocha superior Socha inferior Cano Blanco/Playonera area Vergara and Rodriguez, 1997 SS m. t 100 50 UJ Z UJ O UJ — UJ o -J LST -SBSocha inferior Figure 6-19. Previous sequence stratigraphic models for Colombian Llanos foothills

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156 that is bounded by a sequence boundary encompassing the late Maastrichtian and early Paleocene. This sequence starts with a lowstand systems tract (LST) that correspond to the Socha inferior Formation in the Guadualera section (30 km west of Pinalerita section). This LST is characterized by braided stream deposits. It is dated as late Paleocene based on palynomorphs. The Socha inferior is capped by a TS, that correspond to the Socha inferior-superior boundary; the lower Socha superior is dominated by coastal plain shales and it is dated as early Paleocene based on palynology. Vergara and Rodriguez (1997) also proposed a sequence, Tl, that is bounded at the base of the Socha inferior in the Playonera (~10km northwest of Pinalerita section) and Cano Blanco sections (~ 130km southwest of Pinalerita). The Socha inferior is interpreted as a lowstand system tract (LST). The lower part of the formation is dominated by braided-stream deposits, specially in Cano Blanco area, while the upper part is characterized by arenites with bidirectional curved lamination, with a few coal beds, black mudstones, and fine sandstone-mudstone intercalations that are interpreted as estuarine distributary channels in estuarine environments. This LST is dated as early Paleocene based on palynology, (taxon lists for individual samples are reported in Vergara and Rodriguez , 1997). Rull (1997b) attempted a sequence stratigraphic analysis of two cores in western Venezuela. Using palynomorphs distribution, he proposed more than 12 sequences for the late Paleocene-Eocene interval in the Maracaibo area. Some of the "sequences" do not have either maximum flooding surface (MFS) or transgressive surface (TS), and consist of sequence boundaries (SB) stratigraphically very close to each other, in other cases the "sequence" only contains 2 consecutive MFS. He does not present any lithological, seismic, or paleontological evidence that support his proposed sequences. He used major changes in palynoflora or barren intervals with oxidized kerogen as indicative of sequences boundaries. However, these palynological changes may also be due to climatic changes affecting flora, or laterally changes in depositional environments

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157 (e.g., channel to overbank deposits) rather that a drop in either relative or eustatic sea level. Then, he correlated them to the Haq et al. (1988) cycle chart obtaining a relatively good correlation. However, Pindell and Drake (1998) have shown the dominant tectonic control on the architectural development of the basin, that largely overprint the 3rd order eustatic cycles of the Haq et al. (1988) chart. This makes highly suspicious the good correlation of Rull's "sequences" and Haq's cycle chart. The degree of influence of the chart on Rull's interpretation is not known but appears to be high. Results The three sources of information (palynofacies, palynomorph paleoecology, and lithology) were combined to produce a paleobathymetric curve and sequence stratigraphic interpretation for each section (right side of Figs. 6-15, 6-16, 6-17). Pihalerita section . Five important surfaces were identified in this section (Fig. 615). The first one is a transgressive surface (TS) at 0 meters (Areniscas de El MorroArcillas de El Limbo boundary). This contact is sharp and characterized by bed-load deposits overlaid by suspended load deposits, indicating a rapid increase in accommodation space that can be produced by a rise in base level (Van Wagoner et al, 1990). The second surface, at 105 meters, is interpreted as a maximum flooding surface (MFS). It is characterized by the onset of a bayhead delta onto coastal plain sediments, with well-preserved terrestrial dispersed organic matter and a high abundance of Paleocene coastal plain elements (e.g., Proxapertites). It also recognized by being the boundary between a retrograding parasequence stacking below and a prograding parasequence stacking above (Fig. 6-15). The third surface is identified as a sequence boundary (SB) at 477 meters, at the Arcillas de El LimboAreniscas de El Limbo boundary. It is characterized by a lm red claystone that is probably a paleosoil. This surface puts in contact suspension-load deposits of the upper coastal plain below and bed-

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158 load deposits above indicating a fast facies regression product of a drop in base level (Van Wagoner et ai, 1990). The fourth surface is a TS at 643m, upper Areniscas de El Limbo Formation. Bed-load deposits below and lower coastal plain to estuarine deposits above characterize this surface. The exact location of this surface is tentative because there is a 17.5m covered interval that is immediately below a mudstone sample (660.5m) that contains abundant dinoflagellate cysts and well-preserved dispersed organic matter with marine influence, and immediate above arenites of bed-load environments with palynomorphs and organic matter that indicate fluvial environments (paleoecological group G, palynofacies 6). Therefore, TS could be anywhere within the interval 643660m, but here is assumed 643m because the covered interval could be a mudstone, similar to facies of 660.5 m sample, that would suggest that flooding occur immediately above 640-642m arenite. The last surface is a MFS at 725m and it is identified because of a high abundance and diversity of dinoflagellate cysts (paleoecological group G), well-preserved dispersed organic matter (palynofacies group 5), fine lithology (gray claystone), and a retrograding parasequence stacking below and a prograding parasequence stacking above. Based on these five surfaces and the parasequence stacking pattern (prograding versus retrograding) (see Fig. 6-15), two sequences and 6 systems tracts were recognized. Sequence P. 1 is composed of a lowstand system tract (LST) in the upper Areniscas de El Morro, a transgressive systems tract (TST) in the lower Arcillas de El Limbo Formation (0 to 105 meters), and a highstand systems tract (HST) in the upper Arcillas de El Limbo Formation (105-477 meters). The second sequence P.2, 477-643m, is composed of a LST in the lower Areniscas de El Limbo Formation (lower 166m); a TST, 643-725m, in upper Areniscas de El Limbo (upper 71.6m) to lowermost San Fernando (lower 10.4 m) Formations; and a TST, 725-786.6m, lower San Fernando Formation (meters 10.4 to 72).

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159 Regadera section . Two important surfaces were identified in this section (Fig. 616). The first surface is identified as a MFS at 0 meters, Cuervos-Mirador contact. It is characterized by a red mudstone (paleosoil), and an abrupt facies change from suspension-load deposits of the upper coastal plain below to bed-load deposits of the fluvial plain above. This abrupt facies change indicates a sequence boundary (Van Wagoner et al, 1990). The next important surface is at 285.5m, Mirador-Carbonera contact, and is recognized as a transgressive surface (TS). It is characterized by a fast facies change from mixed-load to suspension-load deposits with a coastal plain flora (paleoecological group F), palynofacies indicating high water tables that are more common in lower fluvial to coastal plain deposits (palynofacies groups B. C, and D), and lithofacies that suggest coastal plain deposits (abundant burrow trails, lenticular lamination) Based on these two surfaces and the parasequence stacking pattern (see Fig. 6-16), two sequences and 3 systems tracts were recognized. For the first sequence, R.l, only the upper part of the HST was studied, the upper Cuervos Formation. The second sequence, R.2, also was partially studied, and it is composed of a LST, meters 0 to 285.5, Mirador Formation, and a TST which only the lowermost part, 285.5-307.5m, was studied (lower Carbonera Formation, meters 0 to 20.5). Uribe section . Two important surfaces were identified in this section (Fig. 6-17). The first surface is identified as a MFS at 0 meters, Lisama-La Paz contact. It is characterized by an abrupt facies change from suspension-load deposits of the upper coastal plain below the surface to braided channels of bed-load deposits in the fluvial plain above the surface. This abrupt facies change indicates a sequence boundary (Van Wagoner et al, 1990). The next important surface is at 1046m, La Paz-Esmeraldas contact, and it is recognized as a TS. It is characterized by a fast facies change from mixed-load (lenticular amalgamated quartzarenites) to suspension-load deposits (light-

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160 gray claystones). Unfortunately, palynofacies and palynomorph paleoecological data above and below this interval are lacking because all analyzed samples were devoid of palynomorphs and dispersed organic matter precluding a confirmation of this interpretation. Based on these two surfaces and the parasequence stacking pattern (see Fig. 6-17), two sequences and 3 systems tracts were recognized. For the first sequence, U.l, only the upper part of the HST was studied, the upper Lisama Formation. The second sequence, U.2, also was partially studied, and it is composed of a LST, meters 0 to 1046, Lisama Formation, and a TST which only the lowermost part, 1046-1066 5m, was studied (lower Esmeraldas Formation, meters 0 to 20). Discussion The basin geometries during the Paleocene in Colombia are very complex and they do not seem to fit a single model (Bayona and Jaramillo, 1998). From the literature, it is evident that the northern part of the Middle Magdalena area (area of Uribe section) behaved as a foreland basin during the Paleogene (Porta, 1974; Pava, 1984; Cooper et ai, 1995; Gomez, 1998). The area of Catatumbo (Regadera section) was not connected with the northern Middle Magdalena because the Santander massif was already uplifted (Etayo-Serna et ai, 1983; Fabre, 1983), and it seems to be related to the Maracaibo Basin to the northeast. Geology in the Colombian Llanos foothills is very complex as Guaicaramo fault system has had significant horizontal W-E shortening (~ 100km according to Dengo and Covey, 1993) as well as N-S displacement (Montes, personal communication). All data suggest that sediment source was mainly the craton (Vergara and Rodriguez, 1996), although tectonic subsidence could be related to the foreland formed east of Central Cordillera at the beginning of the Tertiary (Cooper et ai, 1995). This suggests that stratal geometry of the Llanos/Llanos foothills does not have a physical connection with the Middle Magdalena facies and it acted as a passive margin as

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161 sediments were derived from the craton and subsidence increased basinward. Given these considerations, the sequence stratigraphic hypothesis for each section will be discussed separately as probably they were not part of the same depositional system and were subject to different relative sea level histories. Uribe area (foreland in Northern Middle Magdalena area) . Sequence stratigraphy in a foreland basin is fundamentally different from passive margins where models originally developed. While in passive margins the subsidence rate increases away from land, in foreland basin it decreases. Subsidence in foreland basins is mainly due to flexural isostatic compensation of the lithosphere in response to tectonic loading in a convergent orogeny (Johnson and Beaumont, 1995). During a thrust event, subsidences of the foreland and back bulge basins increase while forebulge is uplifted (Fig. 6-20). This produces an increase of accommodation space in foreland and backbulge basins and a decrease in forebulge basin. Through time, the thrust load migrated cratonward producing a migration of axis of maximum subsidence cratonward (Giles and Dickinson, 1995). These unique characteristics of foreland basins result in different stratal patterns from those predicted in classic sequence stratigraphic models. However, the basic principles of sequence stratigraphy still can be applied (Posamentier and Allen, 1993). In foreland basins there are two tectonostratigraphic zones, A and B. In zone A the subsidence rate is higher that maximum eustatic fall, while in zone B it is lower than maximum eustatic fall. Depending on the location of the shoreline (zone A and B) the stratal architecture would be different (Fig. 6-21). A type 2 sequence boundary would developed if the shoreline is in zone A during a eustatic fall (Posamentier and Allen, 1993). A type 1 sequence boundary would developed if shoreline is in zone B during a eustatic sea level fall (Fig. 6-21, Posamentier and Allen, 1993).

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162 L u E — 5 •S u E | 'f -o c cd 1 o >> g w — T3 C Sea « « O o 7_ C 3 £ 3 X) « 4) O — C3 es ° 'C ^ a g B c .gj u ir. a c M 2,5 18 lj CO Cfl 5! X) U u c u o o — _ T3 3 TJ o y u u. O B ed 3 O oa pj co o

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163 When west shoreline is in zone B A thrust sheets subsidence rate> eustatic rate Zone A subsidence rate< eustatic rate Zone B equilibrium point tectonic hinge point subsidence rate< eustatic rate, but sediment is derived from craton ZoneC Figure 6-21. Sequence stratigraphy and subsidence profile across foreland basins. SMST: shelf-margin systems tract LST: lowstand systems tract (modified from Posamentier and Allen, 1993, and Cooper et al., 1995)

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164 The stratal patterns of the section in Uribe indicate that this was accumulated in zone A (see Fig. 6-21) as fluvial sedimentation occurred at different rates, resulting in channel clustering when accommodation space decreased, but always within fluvial zone as predicted for this zone of the foreland (Posamentier and Allen, 1993). The Uribe sequence stratigraphy suggest an abrupt change in accommodation space and/or advance of thrust front, that produced the sequence boundary at the base of U. 1 (base La Paz Formation, Fig. 6-17). Fluvial arenite facies of La Paz lowstand systems tract (LST) indicate a net decrease in generation of accommodation space in relation to the highstand systems tract (HST) of Lisama Formation and transgressive systems tract (TST) of Esmeraldas Formation. This decrease in accommodation space could be due to an eustatic sea level fall (Posamentier and Allen, 1993) or a decrease in flexural loading (Giles and Dickinson, 1995). However, no evidences of an incised valley was found, and only a channel amalgamation was produced. An alternative hypothesis implies the advance of the thrust front during this interval that resulted in a net facies progradation (fluvial prograding over coastal deposits). Also, a change in weathering and erosion rates product of climatic change can lead to facies change. The analysis of additional sections in this basin is necessary to confirm any of these hypotheses. This sequence boundary at the base of la Paz is recognized over all the basin, although for some authors it is encompassing a large amount of time, including early and middle Eocene times (Dengo and Covey 1993, Cooper et al. 1995; Ramon and Cross, 1997; Suarez 1997a, b; Villamil and Restrepo, 1998). This time-gap does not seem to be supported by the palynostratigraphy of the Uribe section (Fig. 5-12), although samples immediately above and below the sequence boundary (SB) were sterile. Sedimentation of La Paz took place in synclines while erosion developed in anticlines (Julivert, 1961; Fabre, 1983). This large time-gap, therefore, is probably not regional and only restricted to anticlinal areas because in synclinal areas (as in the Uribe section) this time-gap is not recognized (Julivert, 1961). Probably the time-gap, where present, started during the

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165 accumulation of the Lisama (Paleocene), as in many areas west of the Salinas fault, Lisama is absent from anticline axis, and it is in angular unconformity above Cretaceous sediments in anticline flanks (Julivert, 1961). The situation during the uppermost Paleocene and lower to middle Eocene in the Uribe area could be similar to the zonation of the modern foreland basin adjacent to the central Andes described by Horton and DeCelles (1997) (Fig. 6-22). There, the foreland is divided into 4 zones: wedge-top, foredeep, forebulge, and backbulge (Horton and DeCelles, 1997). The wedge top would constitute the middle Magdalena Valley west of the Salinas fault; in this area stratum accumulate on top of actively growing structures of the orogenic wedge, containing thrust-fault and associated folding of the orogenic wedge. The foredeep would constitute the area east of Salinas fault where Uribe section is located. In this zone the accumulation is thick and continuous. The forebulge would be the Chucuri flexure where La Paz is absent, that is a structural high where erosion or nondeposition is predominant. The backbulge does not seem to have an analog in the Eocene. It is unclear if this foreland zonation would apply to the southern part of the middle Magdalena area for the same time interval, and seems to be more complicated, with several subbasins in a broken composite foreland basin and probably isolated from Llanos foothills and Llanos areas (Gomez, 1998). Pinalerita area (craton-derived sediments, passive-like margin) . The sequence stratigraphic model for the Pinalerita agrees for the most part with that proposed by Cooper et al. (1995) and Cazier et al. (1995) for the Cusiana area, and the Guerrero and Sarmiento (1996) for the Guadualera area and Vergara and Rodriguez (1997) for the Cano Blanco-Playonera area (Fig. 6-19). However, these "robust" correlations are lost when ages of depositional sequences are compared (Fig. 6-23). Can these sequences be correlated, are age determination incorrect (misidentifications), or are different authors using different criteria for assigning ages? Answers to these questions are difficult to

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166 N \ Salinas / / ) fault / 1 I ) northern Middle Magdalena Valley Barranca Magdalena river 100km I | Tertiary Triassic/Jurassic Basement and plutons Salinas fault Uribe section Chucuri flexion fold-thrust belt fl backbulge 7777777777mm craton Hi foreland basin B Figure 6-22 . Middle Magdalena Basin. A. Map of major tectonic elements and stratigraphic units. B. Location of Uribe section in a schematic cross section of northern Middle Magdalena Valley foreland basin system during the Eocene (after Horton and DeCelles, 1997).

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167

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168 evaluate, especially with Cooper et al. (1995) and Cazier et al. (1995) works, because they did not provide data supporting age determination. It is striking, however, that "Cuervos" age by Cooper et al. (1995, Fig.4 and text) is late Paleocene while it is early Eocene for Cazier et al. (1995, text) and for Cooper et al. (1995, Fig. 6) (see Fig. 6-19). Guerrero and Sarmiento (1996) provided palynological range chart used for dating the Paleocene sequence. Their data only contains one sample comparable with Pinalerita (in their lower part of Socha Superior, see Fig. 6-19). This sample has first appearance datum (FAD) of Foveotricolpites perforatus which occurs at 81m, in the lower part of Arcillas de El Limbo in the Pinalerita section (Fig. 5-12). Therefore, these two units are isochronous. However, Guerrero and Sarmiento (1996) consider this sample as lower Eocene (Ypresian) without further comment. This interpretation is not supported by graphic correlation performed in this study that resulted in FAD of Foveotricolpites perforatus to be within late Paleocene. Assuming that key surfaces (sequence boundaries, transgressive surfaces, and maximum flooding surfaces) are part to the same depositional sequence, it could be argued that they correspond to chronostratigraphic surfaces and could be used for correlation purposes (Van Wagoner et al, 1990). Then, the sequence PI of Pinalerita section (Areniscas de El Morro-Arcillas de El Limbo) would correspond to Tl (Vergara and Rodriguez, 1997), ST2 (Guerrero and Sarmiento, 1996), and T20 (Cooper et al, 1995) sequences (Figs. 6-23, 6-24). However, there is a difference. Is the transgressive surface (TS) at the middle Barco Formation in Cooper et al. (1995) scheme correlated with the TS at top of the Areniscas de El Morro in Pinalerita and at the top of the Socha Inferior in Guerrero and Sarmiento (1996)? Without proper dating it is impossible to test this hypothesis (Fig. 6-23). A second possibility is that the transgressive surface (TS) at the middle of Barco corresponds to a TS in the upper Arenisca de El Morro that was not recognized in this study. In the Pinalerita section only the last 3 meters of this formation were studied and palynological samples were almost sterile. In a nearby section (10km

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169 72.5W 5.5N 73W Figure 6-24. Simplified map of the Llanos foothills showing major structural features and sections referred to in this study (After Cooper et al., 1995).

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170 northwest), Vergara and Rodriguez (1997) found evidenced of marine influence (bidirectional cross-bedding) in the upper Socha Inferior. On the other hand, Guerrero and Sarmiento (1996) did not find evidence of marine influence in the Socha inferior Formation in a section 30km west of La Pinalerita. The topology of the sequence P. 2 in Pinalerita is very similar to T30 to lower T40 in Cusiana area (Cooper et al. 1995; Cazier et al, 1995). A lowstand systems tract (LST) in lower Areniscas de El Limbo (or "Mirador" in Cooper et al, 1995), a transgressive systems tract (TST) in upper Areniscas de El Limbo and lowermost San Fernando (Cooper et al, 1995 considered the TST to include only the upper part of "Mirador"), and a highstand systems tract (HST) in the lower San Fernando (Cooper et al, 1995 included all of "Carbonera"). The TS at the upper Areniscas de El Limbo in Pinalerita is well supported by palynology (dinoflagellate cysts, coastal plain pollen), and lithology (Thalassinoides). The maximum flooding surface (MFS) at lowermost San Fernando is also well supported by a high abundance and diversity (more than 10 species) of dinoflagellate cysts, palynofacies (group 5) in sample 725m, and the parasequence pattern, regressive estuarine muds prograding over transgressive tidal-estuarine muddy sands or estuary-mouth sands, as observed in Gironde estuary, France (Allen and Posamentier, 1993). Samples above and below, although of similar muddy facies, decrease in abundance and diversity of dinocyst indicating less marine influence. The topology of this P.2 sequence is very similar to that modeled by Zaitlin et al (1994) (Fig. 6-25) and observed by Allen and Posamentier (1993) in Quaternary incised valley fillings in the Gronde estuary, France. There, the fluvial valley incised during the last sea-level fall is being filled. The sequence comprises a LST of fluvial gravel and coarse sands, a TST that comprises the bulk of the incised valley and forms a landwardthinning wedge of tidal-estuarine sands and muds, that in the estuary mouth are overlain by a thick, coarse-grained tidal-delta and estuary-mouth tidal-inlet sands. The HST forms a prograding, tide-dominated estuarine bayhead delta that is still filling the valley. In the

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171 Time 3 TST barrier Pinalerita section non-incised fluvial lagoon bavhead incised-valley delta fuvial Figure 6-25. Schematic location of Pinalerita section in a plan view of a simple incised-val filling during a relative sea level fall and rise cycle (times lto 4). SB: sequence boundary, LST:lowstand systems tract, TSTrtrangressive systems tract; HST:highstand sytems tract (adapted from Zaitlin etal., 1994)

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172 interfluves, the sequence boundary is expressed as a wave ravinement surface with TST and HST unconformably overlying Pleistocene or Tertiary substrates. The whole sequences (P. 1 and P.2) seems to be prograding in a northeast direction as thickness increases toward south (Figs. 6-23, 6-24), and paleocurrents and petrofacies (Vergara and Rodriguez, 1996) indicate that sediment source was the craton during the accumulation of lower P. 1 . Regadera area (Santander and Craton-derived sediments) . The Regadera area was in a different basin (Catatumbo area) separated from Middle Magdalena Basin by the Santander Massif that was already uplifted by the Paleocene (Fabre, 1983; Etayo et al, 1983; Cooper et al, 1995). An abrupt decrease in accommodation space is marked by the sequence boundary of R.2 Sequence. The Mirador L ST is capped by a flooding surface that appears to have regional significance (Fig. 6-26). No evidence of an incised valley was found. Eocene sediments of the Maracaibo Basin probably were derived from the Santander Massif and the craton and systems prograded toward the Maracaibo Gulf (Fabre, 1983; Colmenares and Teran, 1993). There are no sequence stratigraphic studies of the area, and very few published sections in the area present paleontological data of any kind. Only one section (Gonzalez, 1967) presents a pollen range chart. Another paper presents some general palynological data but the distribution of taxa is not showed (Colmenares and Teran, 1993). In general sediments in Catatumbo area seem to be prograding toward the Maracaibo Gulf, and sediment sources were the Santander Massif and the Merida arch (Colmenares and Teran, 1993). This basin probably was isolated from both Middle Magdalena (Uribe) and Llanos foothills (Pinalerita) during the Paleocene-Eocene, as consequently their stratal architectures do not seem to correlate. Overall Se quence Stratigraphy . The three sections seem to be located in three separate basins (Llanos-westem Eastern Cordillera; Middle Magdalena Valley; and

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173

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174 Catatumbo-Maracaibo areas). During the late Paleocene-Eocene, each basin probably had a different subsidence, sediment source, and sediment accumulation history. Therefore, stratigraphic sequences proposed in each section should be particular to each basin. However, two stratigraphic horizons could be identified in all three basins (Fig. 626) , suggesting that they were formed in response to large-scale tectonic and/or eustatic events. The first one is the sequence boundary during the Lowest Eocene. The second is the regional flooding during the middle Eocene. This flooding was seen in Pinalerita (Foothills), Regadera (Catatumbo), and Tl Well (Maracaibo). In Uribe section, this flooding seems to correspond to a parasequence boundary (meter 575). Environmental information that could confirm this flooding in the Tibui, Paz de Rio, and Rubio Road sections is lacking Finally, chronostratigraphic correlations based either on formational names or lithology are very suspect. The comparison of diverse localities indicate that very often a formational boundary or lithological change does not correspond to a time line (Fig. 627) , especially in areas like Colombian Paleogene with several small basins with different subsidence and sedimentation histories. However, Colombian geological literature is filled with chronostratigraphic correlations of this sort (Porta, 1974). It is evident that extensive paleontological studies are very necessary for an adequate understanding of the history of this region.

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175 N to 5 C 4) 10 O C c e on Uo. T3 J. 1 53 1 1 1u U D k. C3 5 o re E 00 1 B 2 3 8 8 0 s. E ~ o o Uc/5 ii|i n iiiii i j iii m 1 1 1 w w t iiiiii 1 8 8 8 ° m — > 3N3303 3N3303 31QQIN I I 3N3D031Vd tfSddH J 4 |3 .Er"re o -h N 00 O > c IS £ ^ c O cz to JS s E O TO ~ 2> « o* n. « c 00 E E "I o a Sal u fc O u f §»8 , U.UO

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CHAPTER 7 DIVERSITY The late Paleocene-early Eocene interval is characterized by a long period of global warming that culminated in the Eocene Thermal Maximum, the highest ocean temperature of the last 65 million years. The warming has two distinct peaks, at the Paleocene-Eocene boundary and in the middle to late early Eocene (Wing et al, 1995). The warming at the Paleocene-Eocene boundary, or late Paleocene Thermal Maximum (LPTM, Zachos et al, 1993) is recognized by a rapid world-wide warming of high to mid-latitude surface waters, change in ocean circulation, and deep-water oxygen deficiency (Miller et al, 1987; Kennett and Stott, 1991; Pak and Miller, 1992; Zachos et al, 1993; Bralower et al, 1997); this event also has been detected in the Caribbean (Bralower et al, 1997). The LPTM correlates with a 35% decrease in plant diversity in mid-latitudes of North America (Wing etal, 1995; Wing, 1998), and a dramatic mammalian turnover (Clyde and Gingerich, 1998) in North America and Europe. Tropical planktonic foraminifera diversified during this time (Kelly et al, 1998), while deep-sea benthic foraminifera suffered a major extinction (Pak and Miller, 1992). The LPTM is associated with a large and abrupt negative excursion of stable carbon isotope of marine and terrestrial materials (Koch et al, 1992; Kennett and Stott, 1991). This spike could be due to dissociation of methane hydrates because of the fast warming of deep waters (Dickens etal, 1995), although this hypothesis is still highly controversial (Bralower et al, 1998; Dickens, 1998) The late early Eocene (or Eocene Thermal Maximum) is recognized as having the highest temperature in the last 65 million years (Wolfe, 1978; Wolfe and Poore, 1982; Miller et al, 1987; Prentice and Matthews, 1988) greatly affecting the vegetation in both 176

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177 southern and northern middles to high latitudes where an important increase in plant diversity has been documented (Askin and Spicer, 1995; Christophel, 1995; Wing etai, 1995; Wing, 1998). Competing models exist for explaining the early Eocene warming. Increases in both greenhouse gases and oceanic heat transport have been proposed to explain the nature of this warm climate (Rind and Chandler, 1991; Pak and Miller, 1992; Sloan and Barron, 1992; Sloan etai, 1995). When levels of atmospheric C02 similar to preindustrial values are used, a slight cooling in terrestrial tropical environments especially for South America is produced (Sloan and Rea, 1995; Sloan and Morrill, 1998). On the contrary, when CO2 levels six times higher are used (greenhouse model), land temperature in tropics rises by 4 degrees Celsius and soil moisture decreases (Sloan and Rea, 1995). Precipitation over equatorial land does not change in either scenario of CO2 concentrations (Sloan and Rea, 1995). Data from oxygen isotope values of planktonic and benthic foraminifera for the late Paleocene to early middle Eocene indicate that tropical sea surface temperature did not change during this time interval, with values similar to the Holocene (Zachos et al, 1994), although, the datapoints analyzed from tropical regions were very few (one site for the late Paleocene, two sites for the early Eocene, and no sites for the early middle Eocene). No data from terrestrial tropical regions are available to test these models and further contribute to our understanding of these examples of global warming. Changes in tropical vegetation would be expected if climate was also drastically modified in tropical areas during this time. An abrupt departure from previous environmental conditions, well beyond the normal ability of plants to adapt, can produce extinctions, rapid immigrationemigration, and ecological replacement (Niklas, 1997). High annual rainfall and/or little dry-season stress are correlated to a high number of plant species in lowland neotropical forests (Gentry, 1981; 1988), therefore, in a greenhouse scenario, a decrease in plant diversity could be expected as effective

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178 precipitation and soil moisture decrease, and water-stress increases. On the other hand, an increase in plant diversity would occur in a slightly cooler tropical region as effective precipitation and soil moisture increases. Thus, analysis of plant diversity, seen through the pollen and spores record, could provide data to assess the validity of climatic models for the late Paleocene-middle Eocene warming interval. Previous Studies Studies addressing plant diversity in the Paleocene-Eocene of the tropics have not been published. Most of palynological studies have focused in biostratigraphy, that tends to use a small part of the total pollen/spores flora found in a sample. However, several authors have suggested that Eocene floras seem to be more diverse than during the preceding Paleocene. Van Hoeken-Klinkenberg (1966) in the Eocene of Nigeria found an increase in morphological variety of species and especially the presence of abundant small triporate and brevicolpate grains. Gonzalez (1967) in Catatumbo area noted an explosive development of angiosperms at the Paleocene/Eocene boundary with more than 20 new species arising and angiosperms becoming dominant. Colmenares and Teran (1993) also reported a high pollen diversity at the early Eocene (Mirador Formation) in southwestern Venezuela and subsequently decreasing in the Carbonera Formation (middle Eocene-Oligocene). Analysis of diversity based on pollen and spores must be done very carefully, as several taphonomic and sampling artifacts can affect the diversity of a sample. In fluvial environments, for example, channel-fill and crevasse-splay environments tend to have more species because they are more open to transported palynomorphs and changing physical environmental conditions (Potter, 1976; Farley, 1990). In the delta of the Orinoco river transport of pollen is restricted, and pollen of the local swamp forest is dominant in the sediments, while offshore the pollen is better mixed (Muller, 1959). There is a trend toward higher diversity values (Simpson index) from fluvial to deltaic

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179 environments (Nichols and Traverse, 1971). Also, a systems tract can exert a control on the pattern of number of species observed (Holland, 1995). However, in spite of these multiple problems, the pollen and spores record is the most reliable record of plant diversity in tropical regions. Fortunately, there are a number of statistical analyses (see Chapter 3) that can be applied to the raw diversity data to account for the many factors that can exert an effect on temporal and spatial patterns of diversity. Results An analysis of pollen and spores diversity was only performed for the Pinalerita section. The other two sections were not included because the sampling recovery was not adequate for this type of analysis and only the Eocene was studied. In the Pinalerita, on the other hand, the palynomorph recovery was good, sampling was more intense, and both Paleocene and Eocene strata were analyzed. Also, as the comparison PaleoceneEocene is done in same section, the differential preservation due to diverse weathering rates can be minimized. Both Paleocene and Eocene strata were sampled along the same creek, in similar mountain slopes, and separated from each other for about 100-200 meters in horizontal scale. Therefore, a similar weathering rate could be expected in samples taken from either Paleocene or Eocene strata, and differential pollen preservation due to recent weathering would not be expected. Comparisons of the floral assemblages through the entire section was done using detrended correspondence analysis (DCA) as shown in Figure 7la. This analysis was performed on range-through presence-absence dataset of the range chart for the Pinalerita section. Axis 1 values (that explain 22% of variation) in Paleocene strata (5.4 to 311 meters) ranges from 0 to 1 .29 while values in Eocene strata (475 and above meters) fluctuates between 1.8 to 4. Simpson index (SI, expressed as -loge(SI)) for Paleocene samples have a mean of 2.09 (standard deviation SD=0.46), while Eocene samples have a mean of 2.53

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180 (SD=0.60) (Fig. 7lb). The isolated earliest Eocene sample (475m) has an index of 0.71 and was not included in calculation of Eocene index mean. SI means also were calculated for samples arranged according their position in systems tracts: Paleocene transgressive systems tract (TST)= 1.90 (SD= 0.38), Paleocene highstand systems tract (HST)= 2.28 (SD= 0.45), Eocene TST= 2.47 (SD= 0.75), Eocene HST= 2.58 (SD= 0.39). Rarefaction curves produced by the rarefaction calculator (see Methods) are shown in Figure 7-2. Each curve represents the hypothetical relationship between sample size (number of pollen/spores counted per sample) versus number of species found. This allows a comparison of diversities from samples of different sizes. The rarefaction curves also were separated according to the position of the samples in a systems tract. Thus, Paleocene and Eocene transgressive systems tract (TST) were compared with each other, as well as Paleocene and Eocene highstand systems tract (HST) (Figs. 7-3, 7-4). Using rarefaction results, number of species were calculated for each sample at a counting of 1 15 grains (samples with less than 1 15 grains were excluded from analysis). Bootstrapping of this dataset, using 4999 iterations, indicated a species number mean of 31.71 (confidence interval 28.69-34.70) for Eocene samples and a mean of 2 1 .7 1 (confidence interval 18.31-25.01) for Paleocene samples. Mean species numbers do not overlap at 95% confidence interval (P randomization=0.00080). Standing diversity was calculated for each sample throughout the entire stratigraphic interval using the range-through method (Fig. 7-5a). The completeness index (Maas et al, 1995; CI=100*N/Nt, N=number of taxa collected in sample, Nt=total number of taxa including those inferred from range-through method) indicates a mean of 46.3 (SD=25) for Paleocene samples and a mean of 52.5 (SD=20) for Eocene samples (Fig. 7-5a). Rates of taxon first and last appearances were calculated for each sample (Fig. 7-5b). This rate indicated the proportion of first appearance datums (FAD) and last appearance datums (LAD) per standing diversity at each analyzed sample. A background

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181 0 g 1 1§ o c i J y c u 8 s 800 m. 700 -4 600 500 400 300 4J 200 -| 100 0 df 3 4 0 sterile interval Axis 1 score jo w I 5 u c I J u ed B. 800 m. 700 600 500 " 400 " g 300 1 200 " 100 " a a a QT] sterile interval -logSIunb Figure 7-1. Diversity analyses A. Detrended Correspondence Analysis (DCA) of the samples based upon taxa present, axis 1 scores plotted against stratigraphic meters of each sample in Pinalerita section. Axis 1 accounts for 22% of variance. B. -loge(Simpson index) plotted against stratigraphic meters in Pinalerita section

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182

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183

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185 100 -f 1-100 100 200 T 300 . • • >l n n 400 500 600 1 1 1 1 1 1 1 1 1 1 700 me,ers 80 -u 0 late Paleocene early Eocene I middle Eocene TST HST LST TST HST 0.5Q0.4-J C03-) .2 goa2 G o.H o 0 ill. U.i i 100 200 300 I I I I I I I FAD 400 500 600 700 metere 800 late Paleocene early Eocene 1 middle Eocene TST HST LST TST | HST 0.5 Q0.4 3 C0.3-| S CK) .l 0lili m l LAD 100 200 300 i t j i i -i i i i r r t | i i i i i i i i r | I i 400 500 600 m. 700 meters 800 late Paleocene early Eocene ; middle Eocene TST HST LST TST | HST B. Figure 7-5. Diversity analyses. A. Standing diversity of range-through sporomorphs for the late Paleocene-Eocene interval calculated per stratigraphic meter. B. Taxon rates of FAD and LAD for same interval. White box indicates sterile interval. LST:lowstand systems tract, TST:transgressive systems tract, HSTrhighstand systems tract

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186 FAD rate of 0.05-0.12 is observed for both Paleocene and Eocene samples. Background LAD rates also fluctuate between 0.07 to 0.12. Taxa with single occurrences do not add much stratigraphic information or temporal change to the diversity analysis (Wing, 1998) but such taxa could introduce some noise to the general diversity pattern. Therefore, the standing diversity was calculated again without considering taxa with single occurrences (Fig. 7-6a). The general diversity pattern is still very similar to that observed with the whole assemblage. Taxon rates of FAD and LAD also were recalculated considering only taxa with multiple occurrences (Fig. 7-6b). Background rates of FAD and LAD are also similar to each other but lower than rates using whole assemblage, varying from 0.03-0.10 for FAD, and 0.03 to 0.08 for LAD in both Paleocene and Eocene samples. Three FAD rates higher than background were identified at 130m, 690m, and 785m (see ovals in Fig. 7-6b). Two FAD levels higher than background were identified at 35 and 265m (see ovals in Fig. 7-6b). High FAD rates immediately following sterile intervals or at the beginning of the section are probably a sampling artifact. High LAD rates at the end of the section or preceding sterile intervals are also sampling artifacts. Cumulative first appearance datums (FAD) and last appearance datums (LAD) curves were plotted in order to better appreciate the overall change of FAD and LAD rates (Fig. 7-7a). These curves were based on taxa with multiple occurrences. The same interval of faster turnover described above could also be identified. Finally, diversity curve of taxa with multiple occurrences and range-through was plotted but in this case the species were separated in three categories: those restricted to the Paleocene, those restricted to the Eocene, and those with occurrences in both Paleocene and Eocene strata (Fig. 7-7b). Species data indicate a flora of 18 species/sample (SD=4)that occurs in both Paleocene and Eocene strata, a late Paleocene flora of 21 species/sample (SD=6), and an early-middle Eocene flora of 52 species/sample (SD=20).

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187 100-H T CO M 3 C • #of sp. without singles — total tt of sp. r T 100 200 300 400 500 600 700 meters 800 late Paleocene early Eocene i middle Eocene TST HST LST TST HST 0.5 FAD : . . . a V 'J 1,1. 1 .1 Ip. p ,,. £03 B a 2 o.i a 0100 200 300 400 500 600 700 meters 800 0.5 late Paleocene early Eocene I middle Eocene TST | HST LST TST HST r i i i -JjL \ \ i i i i / LAD 1 1 ,1 1 1 p, j! r,r r € I B. late Paleocene early Eocene 1 middle Eocene TST HST I LST TST HST Figure 7-6. A. Standing diversity of range-through sporomorphs using whole dataset and only those taxa with occurrences in more than one sample for the late Paleocene -Eocene interval calculated per stratigraphic meter. B. Taxon rates of FAD and LAD for same interval but excluding taxa with occurrences in only one sample. White box indicates sterile interval. LST.iowstand systems tract, TST:transgressive systems tract, HSTrhighstand systems tract. Dash vertical line correspond to background LAD and FAD. Ellipsoids indicate significant increases in FAD and LAD rates

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188 100 *^ 1 V****/s*/**\. 1 l***********r>>A f************/v \*************\ •**** v ******* '*\ •*******"""*} £r**s**t2 \j[ **** ////.C-IVl If*****. **** l******iT^ **** P******.roc^u€, //// ^y££%Late Paleocene flora v$t?73 W/*****f. _ // 9****////-*\nr \ i >•>» A .i. ) ,\ ^ ) > ^ ,\ iMi'i' * ' * * * * / V7X£/^// *********** y *********** \ 7 , HWiWiHM 100 200 300 400 500 600 700 meters 800 B. late Paleocene earlv Eocene middle Eocene TST HST LST TST HST 1 > ~56.2my Figure 7-7. Diversity analyses. A. Cumulative proportion of taxon FAD and LAD, taxa with occurrences in only one sample are excluded. B. Standing diversity of range-through sporomorphs divided in those restricted to Paleocene, restricted to Eocene, or that occur in both Paleocene and Eocene strata. Taxa with occurrences in only one sample were excluded. White box indicates sterile interval. LST: lowstand systems tract, TST:transgressive systems tract, HST:highstand systems tract. Arrows indicate floral turnover higher than background

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189 Palynoflora of northern South America was compared with assemblages from U.S. Gulf Coast, Central America and tropical Africa (see Chapter 3 for references used in the palynoflora comparison). Table 7-1 summarizes taxa that are shared by both northern South America and Gulf Coast, Caribbean/Central America, and tropical Africa during the Paleocene and Eocene. In Table 7-1, only taxa with first appearances within the Paleocene or Eocene are included. The percentages calculated indicate the proportion of the northern South America palynoflora that is shared with another region in a specific span of time. Eleven-point-five percent of the taxa are shared with tropical Africa during the Paleocene and 1 1 % during the Eocene (here are included taxa appearing during the Eocene in Africa and those that were already present in Paleocene and extend into the Eocene). Zero-point-seven percent of taxa are shared with Gulf Coast in the Paleocene and a 5.25% in the Eocene. Six-point-six percent of taxa are shared in the Eocene with Caribbean and Central America (Fig. 7-8). Paleocene sediments in the Caribbean and Central America have not been studied. Discussion The underlying evolutionary signal of the pollen and spores record is masked by a multitude of factors that also can control their distribution as lithofacies, sample position in systems tracts, differences in sampling intensity, and sample preservation (Nichols and Traverse, 1971; Holland, 1995; Paul, 1998). Therefore, an analysis of pollen and spores diversity must take into account, in the first place, changes due to non-evolutive factors (depositional system tracts, preservation, sampling artifacts) before any inference can be made from the observed diversity pattern. The analysis was done based on a single section, ruling out any possible difference due to differential sample preservation, that is a highly problematic factor in tropical areas where weathering rates are high. Experience has shown that samples taken in old road-cuts would generally produce sterile to low recovery palynological samples,

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190 early middle Eocene Lutetian [50.30 Ma] -90 -45 0 45 Figure 7-8. Paleogeographic map of the early middle Eocene (after Scotese, 1992). Porcentage of shared similarities between northern South America and tropical Africa, Caribbean/Central America, and the Gulf Coast are shown for each zone. Percentages in parenthesis indicate similarities during the Paleocene for same areas. Paleocene data for Caribbean and Central America are not published

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191 Table 7-1. Sporomorph species shared by Africa, Gulf Coast, and Caribbean/ Central America with Northern South America. A=tropical Africa, GC=Gulf Coast, C=Caribbean/Central America, P=Paleocene, E=Eocene. Only are included species with first occurrences in Paleocene or Eocene A GC C TflXA P E P E E affinities paleoecology Annmlnsinitpv iiitpniflPS 1 l Olacaceae Anni/trin/iritPV ivpf^Pfitii i it l f I It l 1 lyLfl lit J IVCf JCffMt i f^rir-ntrinsiritpv nnprrHintttK V_/ ILUl f IL/lsf (it J t/^/C/ L lllLliLl.) 1 T^s'hitrinsiritpv trisin otJitT/irnll C ILL flit t llsUf (icj */ lUfiguiijui mi j l Proteaceae coastal plain 1 sin osinprtitpv tni rmTfWPnifitii^ L^iJF I t^Lll/t 1 lilt J flllisi L/JL/VCfJlL*lUJ I Annonaceae (Lx>ngapertites sp. in GC) f sin ftstnortitoc nr/iY/i np rtt t ni n P f LAJlliillLstZf lilt, J yi UAttfsCf lllUlUC-o 1 Annonaceae J s\*~if~i/~ir~\sjrtit/}c i i/jm oon si on foil ro 1 LAJfigaperiliej Vuii&eflUcitUUf gl 1 1 Annonaceae f\4 'nt/ritii/iitpf frnnri^rni IrliiHf lllttlltCJ J / U/H l.)L'/( 1 Palmae iviuniipiies uj riLUtiuj 1 P vs\ \* s~i no vti to c* s*tircnc r roxupermts cw/jhj 1 1 1 Palmae coastal plain (Proxapertites spp. in GC) Pc/i v/i ntf f z> c hum fop ft si i si P z r fUXLiptZf IffCJ ilU/ill/Ci lUluc j i Wy CIJ I CI 1 LMccill Proxapertites operculatus 1 i I All Iltlt coastal nlain r roxapeniies leniaria i Pa i si msinsir'siinitp c mp/i 1 u c / .I 1 1 CI FF I (_' F 1 1/ L (J t j.' 1 1 to fViClKWJ I Palmae P c 1 1 si tri Ini f z> c »M i n 1 1 1 ! i c rSllCliriLOipUcj fillrlUlUj i i Racemonocolpites racenxatus 1 t i P of i n fo\ ji tiri ff \ /ni f c tn sin (in I si tl J C 1 i\eiiurcviiriLuipiies iriiitiguiLiiUd i i i coastal plain Pott wts\ tisis , si 1 n i to c ro a 1 si ixeiirtioriutoipiico rcgtu 1 Pnlmac* I 1 tX 1 1 1 1 CIV alluvial (Retimonocolpites in C) Poti t *~i f /~\ I Ft i to c /im z? »*i s'Sinsi Ac ((// ILOipiltj ClFFlt I ILClFUl 1 P otitri s^ si / n / #^ c fi si ro n ci c [\t III F Itl'ipi 1 1 j tlLlltFlJlj 1 \rnni 7 sin sir si] nttor cnn OpifllCUFllsLLripilCj) 5UU. 1 1 i 1 Palmae coastal plain (Nypa inGC) Va'm/^/i / n/") 1*7 c msi romsitu? oyriLUipt/fllCj mWigifiuiHj i Vv/ir/i/n/i nf/JC d/~) rim stn c kjyiinjipui ucj pisi tcc/jiUitij i 1 i (Myrtaceadites sp. in GC) I flmni/iptnitpv icrpmrn i Ulml/lUCt^/llCJ A.ICf/ipil 1 i Ulmaceae t\ /~\ tryi fori /"SI S* 1 SI 1 to V SIWIHSIO L>(.' FFl iJLli. Lit tllll t J LUIFILIL i i \/lnl varpar* alluvial Kf ittim si sm/ifpp\yi U ill 1 1 1 1 lit tirlilF t t v I 1 ItPm nisi c tpnfo sin sis'/I /ni c o pnmintti c VJ t III FF ILlJ 1 1 pi IIIFIUL U ipi IC J gCfllFFlLilUJ. 1 ft pti si i nsin tp c nisi a si si iphph ci c fKCllUipUf IIC*>J FFlllt^aCll t Fit IIM j 1 Prntpacf i ae coastal plain rss^ninsis'sis'isiitpv nn/^imipnt/ipn c/ c UL/FI l UU L.LIL tCll It j F Itlt I F 1 1 1 c 1 1 1 UL / /.> 1 J 1 i 1 Malvaceae Hfp\jitri'p/~ifnitpv \jnrinhili c xj/ tin/ 1 (. ( > i j / 1 1 1 j VUF im.niij 1 coastal plain t i s*si trt s*s^ c t c rtsin to c slstfsisioncic x^iLuiritUjisptjriicj uurugcrijij i 1 i ^1 p h 1 7 a p a n p a p coastal plain rr~hmprm/~iritpv pvtpl/ip L-i\,flljsCf ipUl 11 1 J t jit ICR 1 1 Malvaceae alluvial/coastal /ii cf ifn r**/i /"i fz> p itnsiiilsitiic J UjjII F lyU I lit J UtlULilUlUi 1 On?t(yrappap (Ludwigia in GC) Margocolporites vanwijhei 1 1 Fabaceae Monoporopollenites annulatus 1 1 1 Poaceae (C. gramineoides in GC) Perfotricolpites digitatus 1 Convolvulaceae Perisyncolporites pokornyi 1 Malphigiaceae coastal plain Psilatricolporites crassus 1 1 Pellicieraceae coastal plain Psilatricolporites maculosus 1 1 Sapotaceae alluvial Psilatricolporites operculatus 1 1 Euphorbiaceae Psilatricolporites transversalis 1 Burseraceae (cf. Protium in C) Retitricolporites irregularis 1 Euphorbiaceae Spironsyncolpites spiralis 1 alluvial Striatricolpites catatumbus 1 1 1 1 Fabaceae alluvial (aff. Crudia in GC) Verrucatosporites usmensis 1 Polypodiaceae Zonocostites ramonae 1 Rhizophoraceae coastal plain

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192 while samples taken at the same stratigraphic levels along creeks would produce good recovery of palynomorphs. In the Pinalerita section, all samples were taken along the same creek, and probably haven been exposed for the same amount of time under very similar conditions. The completeness index also indicates that there is no major preservational difference between the Paleocene and Eocene samples (Fig. 7-5). A floral change trend through the late Paleocene to early-middle Eocene interval is evident from the detrended correspondence analysis (DCA, Fig. 7-1 a). A similar trend has been noted in the macrofossil plant record of Wyoming Basin across the same time interval by Wing (1998). Superimposed in this trend, however, there is taphonomical and differential distribution of the plant assemblages that produced pollen and spores (DCA first axis only explains 22% of variation). A major problem in estimating diversity is sample size. The number of species increases as does sample size (Rosenzweig, 1995). One the most important uses of "diversity" indexes is to estimate the underlying diversity in small sample sizes (Rosenzweig, 1995). These indexes allow comparisons among samples regardless of the original sample size. In this case that would mean the number of pollen grains that were counted per sample. The Simpson index (SI) indicates that there is a trend toward increasing diversity from the late Paleocene to the early middle Eocene (Fig. 7lb). Holland (1995) found that systems tracts affect the fossil distribution in fossil assemblages. However, the pattern of increase in diversity is maintained even when samples are separated according to systems tracts (-loge(SI)=1.9 in Paleocene transgressive systems tract (TST); 2.28 Paleocene highstand systems tract (HST); 2.47 in Eocene TST; and 2.58 in Eocene HST), suggesting that the position of a sample in a systems tract does not exert a great influence on its diversity. Lithofacies exert major influence on the distribution of fossil pollen and spores, not only by sorting taphonomically different plant assemblages but also differential preservation during the time of deposition. Thus, two samples coming from the same

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193 stratigraphic horizon and close to each other could have different syndepositional preservation according to the position of the water-table at the moment of accumulation. This differential syndepositional preservation is directly reflected in the number of palynomorph grains counted per sample. Thus, poorly preserved samples would have relatively low palynomorph counts and therefore a low number of species. This syndepositional control is evident as shown by the wide fluctuations in the completeness index in both Paleocene and Eocene strata (Fig. 7-5a). One way to account for this difference in syndepositional preservation is rarefaction. Rarefaction analysis indicates that Eocene samples tend to have a higher diversity than Paleocene samples, regardless of the number of grains counted in each sample (Fig. 7-2). This difference is also maintained when similar systems tracts (equivalent to similar depositional environments in this particular case) are compared (Figs. 7-3, 7-4). Thus, the Eocene TST and HST are more diverse than the Paleocene TST and HST respectively, regardless of sample size. Bootstrapping also suggest that the Eocene samples have on average, a higher diversity than the Paleocene samples, regardless of the number of grains counted per sample, or the number of samples analyzed in each interval (P=0.00080). Standing diversity (using range through-method that tends to eliminate facies and sample size effects) suggests that there is an increase in pollen/spores diversity in the late early to middle Eocene strata, from an average of 40 species (SD=8) in late Paleocene samples to 76 species (SD=17) in late early-middle Eocene samples (Fig. 7-5a). The isolated early early Eocene sample (475m) yielded a standing diversity of 29 species, fewer than most of either the Paleocene or Eocene samples. However, this sample could have a strong biofacies control (dominated by Longapertites), that may be producing this low value, although the possibility of a real decrease in diversity could not be fully ruled out. A similar decrease in plant diversity associated with the Paleocene-Eocene boundary has been registered by Wing (1998) in Wyoming. Analysis of standing diversity using taxa with multiple occurrences produced a similar pattern compared to that using the

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194 whole assemblage (Fig. 7-6a). Thus, the late Paleocene is less diverse (38+/-8 species) than the late early-middle Eocene (72+/15 species), and the early early Eocene sample has a low diversity (29 species). Rates of floral turnover indicate three significant levels of first occurrences and two levels of last occurrences above the background rates of first and last occurrences (Fig. 7-5b, 7-6b). The pattern is better appreciated when the noise produced by singleoccurrence taxa was eliminated (Fig. 7-6b). Additional first appearance datums (FAD) peaks at the beginning of the section, at the end of sterile intervals, and at flooding surfaces are sampling artifacts or product of systems tract as modeled by Holland (1995) for marine fossils in nearshore to offshore environments. Last appearance datums (LAD) peaks at the end of a section, just before the beginning of a sterile interval, and in flooding surfaces are also artifacts product of systems tracts or sampling gaps (Holland, 1995). The first important FAD peak is at 130m in the late Paleocene (Fig. 7-6b, 7-7a). It is characterized by a small increase, but above average, in rate of first appearances. The second interval is at 690m (earliest middle Eocene) characterized by a 0. 1 increase in FAD proportion above the background levels. The last peak is at 785 m (middle Eocene) and is similar in magnitude to the 690 interval. This increase in middle Eocene, however, does not account for most of the standing diversity seen in this time interval. Many species probably appeared during the early Eocene stratigraphic interval that was sterile due to the predominantly clean sandstone lithofacies. These hypothetical earlier appearances were seen in graphic correlation (Fig. 5-12) and produced a high rate of first appearances in the first samples following the sterile interval (Fig. 7-6b). High rates of FAD are observed at 35m and 265m in the late Paleocene. The last one is considerably significant (0.2 above background level) and produced an important decrease in the late Paleocene flora (Fig. 7-7b) at the end of the late Paleocene, 155 m (approximately 1.7my) below the suggested position of the Paleocene-Eocene boundary defined by P5/P6 boundary (54.5my). This event could be comparable to the latest Paleocene floral

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195 extinction observed in the Bighorn Basin by Wing (1998). The extinction occurred during the late Clarkforkian and earliest Wasatchian ages (55.7 my, slightly below the LPTM Carbon isotope excursion). This extinction extended to the later part of C24r (~54.2my). However, confirmation of this correlation is uncertain because of the poor control in time calibration of the Composite Section developed in this study (see Chapter 5). Nevertheless, the similarity of the pattern and its timing deserves further consideration. From the overall analysis, two patterns are evident. First, there is an extinction of a late Paleocene flora, restricted to a stratigraphic interval starting 155 m (~1.7my) below Paleocene/Eocene boundary (at 420m, as defined by P5/P6 boundary at 54.5my) and lasting at most to meter 475 (~0.6my above P/E boundary) that has already evidences of an Eocene flora (Fig. 7-7b). The internal structure of this extinction is uncertain because most of this interval was either sterile or covered. Second, there is development of an early to middle Eocene flora that is approximately twice more diverse than comparable samples from the late Paleocene strata. Most of this rise in diversity should have occurred during the early Eocene, interval that was sterile and thus not observed. The topology of this increase, therefore, is still uncertain, but it could be produced by pulses as the two observed in the middle Eocene, rather than a gradual accumulation of species. This overall pattern of plant extinction followed by increase in diversity was observed in the Bighorn Basin in Wyoming (Wing, 1998). Wing suggested that pulsed global warming (warming at the late Paleocene Thermal Maximum (LPTM) followed by cooling and then warming again at early Eocene) and intercontinental migration were the principal causes that explain the observed pattern. The similarity with the pattern found here suggests that climate in tropical terrestrial latitudes changed during the LPTM and subsequent Eocene global warming. Wing (1998) could not explain why LPTM warming produced an extinction while early Eocene warming produced a rise in diversity. Gentry (1988) found correlation between tropical lowland rainforest diversity and annual rainfall

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196 (and/or water stress). Therefore, it is possible that diversity pattern indicates that LPTM in the Neotropics was a time of net decrease in effective rainfall. This interpretation agrees with predictions of LPTM climate models (Sloan and Thomas, 1998) of reduced July mean monthly precipitation, reduced soil moisture content, slight decrease in mean monthly surface temperature (~1C), and reduced moisture flux (net evaporation) for the tropics of northern South America. The increase observed in plant diversity in the Neotropics during the Eocene could be related to the effects of the "Eocene Thermal Maximum" event. A net increase in effective rainfall would be expected as suggested by correlation of neotropical lowland forest diversity and rainfall today (Gentry, 1988). This interpretation would agree with early Eocene climate models that predict a slight cooling of tropics lands decreasing net evaporation and increasing effective rainfall (Sloan and Rea, 1995; Sloan and Morrill, 1998). It also would support to some extent oxygen isotope data that show cooling in tropical sea surface temperature (Shackleton and Boersma, 1981), although Zachos etal, (1994) using also oxygen isotopes suggest that sea surface temperature was similar to present values. Adams et al (1990), using nearest-living-relative method on paleontological evidence from larger foraminifera, mangroves, and corals, also suggest that sea surface temperature was similar to present values. A more refined calibration of biostratigraphic framework than that developed in this study, however, is necessary to evaluate the timing of these changes in relation to oxygen isotopes (Miller etal, 1987), and geologic time table (Berggren etal, 1995b; Berggren and Aubry, 1998). Nevertheless, it seems that climate changed in the tropics affecting biota, which challenges views of a constant tropical climate (Adams et al, 1990) where high diversity is accumulated by low extinction rates (Stebbins, 1974). Data presented here support the contrasting view of Jablonsky (1993) that the tropics are a continuous source of evolutionary novelty and not simply a refuge that accumulate diversity because of low extinction rates.

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197 Distribution of the palynoflora in northern South America indicates that there was a low floral exchange with the Gulf Coast and Caribbean during the Paleocene and Eocene. Similar results were found by Graham (1992) who found an Eocene CaribbeanSouth America similarity of 2.6% (using unnamed similarity index= (a/(b+(c-a))*100, a=number of common species, b=species in Caribbean, c=species in South America). Only 6.6% of taxa are shared with Caribbean area and 5.2% with the Gulf Coast during the Eocene, and 0.7% during the Paleocene with the Gulf coast (Fig. 7-8, data from Paleocene of Caribbean is not available). A large percentage of those shared taxa (30%) have coastal plain preferences (Table 7-1), including Spinizonocolpites (Palmae), Psilatricolporites crassus (Pellicieraceae), Proxapertites (Palmae), and Brevitricolpites. Thirty-five percent of taxa shared with Caribbean region are also present in Gulf Coast, 25% are in the Gulf Coast but absent in the Caribbean, and 40% are in Caribbean and absent from Gulf Coast. This low percentage of shared taxa suggests a very limited exchange of floras between northern South America and Caribbean/Gulf Coast regions during the Paleocene-Eocene as was previously suggested by Graham (1992). Most of this change was limited to coastal plain environments. Migration seems in two opposite directions: from north to south in taxa as Cicatricosisporites dorogensis (Schizaeaceae), Ulmoideipites krempii (Ulmaceae) and Bombacacidites nacimientoensis (Malvaceae) which first appearances occur in the Paleocene in Gulf Coast, and in the Eocene in northern South America. South to north migration occur mostly in coastal plain elements as Proxapertites (Palmae), Spinizonocolpites (Palmae), Brevitricolpites, Psilatricolporites crassus (Pellicieraceae), and Zonocostites ramonae (Rhizophoraceae). Also other noncoastal plain elements migrated toward the north as Mauritiidites (Palmae), Longapertites (Palmae), Syncolporites poricostatus (Myrtaceae), and Striatricolpites catatumbus (Fabaceae). Most of this migration probably occurred during the Eocene, as all of those taxa have first appearances in the Eocene of the Gulf Coast and Caribbean while they have their first appearances during the Paleocene and early Eocene in northern South

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198 America. This northward migration could be correlated with the Eocene Thermal Maximum that expanded tropical zones into previously subtropical areas (Sloan and Rea, 1995). Pitman et al. (1993) proposed possible intermittent arcuate connections between Central America and South America during the Campanian to middle Eocene interval. Data present here suggest that at least during the Paleocene this corridor did not exist, or at least was not used for floral elements to migrate south or northward. During the Eocene, however, a corridor may have existed allowing floral interchange enhanced by expanded tropical zones. Tropical Africa and tropical South America shared 1 1.5% of their taxa in the Paleocene. Thirty-one percent of this flora shared are coastal plain elements such as Proxapertites (Palmae), Spinizonocolpites (Palmae), and Retidiporites (Proteaceae) among others (Table 7-1, Fig. 7-8). This 1 1.5% appeared both in Africa and South America during the Paleocene. However, the direction of migration is still uncertain due to the lack of chronostratigraphic resolution in both areas. During the Eocene the shared taxa decreased slightly to 1 1% (Table 7-1, Fig. 7-8). Sixty-four percent of those shared taxa appear, both in Africa and South America, during the Eocene. Thirty-three percent of them are coastal plain elements such as P. pokornyi (Malphigiaceae), P. crassus (Pellicieraceae), and E. estelae (Malvaceae). Others are alluvial plain elements such as Psilatricolporites operculatus (Euphorbiaceae), Retitricolporites irregularis (Euphorbiaceae), Monoporopollenites annulatus (Poaceae), Momipites africanus, Perfotricolpites digitatus (Convolculaceae), and Verrucatosporites usmensis (Polypodiaceae). These phytogeographic patterns indicate that floral interchange between eastern and western Gondwana occurring into the late Cretaceous (Coetzee, 1993), continued during the Paleogene in spite of the increasing distance of these two continents since early Cretaceous times when they started to split apart (Pitman et al, 1993; -2000km in middle Eocene, 3300km today). The importance of this continuing Paleocene-Eocene floral interchange has not been recognized by many authors (e.g.,

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199 Coetzee, 1993; Romero, 1993). Raven and Axelrod (1974) recognized the possibility of direct migration during or before Paleocene. This Paleogene interchange has been recognized in other groups like chiclid, nandid, synbranchd, and cyprinodontiform freshwater fishes (Lundberg, 1993), most reptile families (Bauer, 1993), and coccyzine birds (Vuilleumier and Andors, 1993). The phytogeographic patterns also indicate that latitudinal control of vegetation distribution is stronger than distances between continents, thus, while Gulf Coast/Caribbean were 1200km apart from northern South America during Eocene (Pitman et ai, 1993), Africa was 2000km apart from northern South America (Scotese, 1992) and still had a stronger floral interchange with South America. This lateral distribution of mainly coastal plain floras also could be further enhanced by the southern Tethys current patterns. There is another plausible explanation for those shared taxa between tropical Africa and Neotropics during the Paleocene and Eocene. Those taxa could have speciated in subtropical areas during the late Cretaceous when the two continents were still close to each other. Then, because of the Paleocene/Eocene climatic change, they migrate into more tropical regions and consequently appeared in the tropical fossil record. However, those shared taxa have not been found in subtropical areas during the late Cretaceous. Therefore, at this time, this hypothesis has only weak support.

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CHAPTER 8 CONCLUSIONS The analysis of palynomorphs and dispersed organic matter distribution in three stratigraphic sections in the Eastern Andes of Colombia led to the following conclusions. A biostratigraphic framework was constructed for the late Paleocene-middle Eocene interval, using the technique of graphic correlation. This framework consists of a Composite Section (CS) that has the earliest first appearance and latest last appearance datums for the most common and/or stratigraphically important taxa found in this study (Table 6-2). Correlations of the three sections analyzed and two more extracted from the literature indicate that there is not an extensive time gap encompassing the early and middle Eocene in Eastern Andes of Colombia in the sections studied (Figs. 5-1 1, 5-12), contrary to what several authors have previously suggested (e.g., Dengo and Covey, 1993; Cooper et al, 1995). Previous palynological zonations for the area (Germeraad et al, 1968, Regali et al, 1974, Muller et al, 1987) have serious inconsistencies and have a poor resolution for the late Paleocene-Eocene interval. On the contrary, the CS produced in this study, has a higher resolution, and constitutes a hypothesis that can be continuously tested as further information is gathered from surrounding areas. The CS was calibrated using foraminifera data and radiometric ages from tropical Africa. Unfortunately, this type of information from northern South America has not been published. Composite unit 0 of the CS is still within the late Paleocene, the Paleocene/Eocene boundary (54.5 my) was defined at composite unit 420, while the early-middle Eocene boundary (49 my) was located at composite unit 640 (Fig. 5-16). The Paleocene/Eocene boundary was defined by the P5/P6 foraminiferal boundary. Absolute ages, epoch boundaries, and foraminifera zonation followed Berggren et al. 200

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201 (1995b), and Berggren and Aubry (1998). Calibration of this CS, however, is still poorly resolved, and there is a need for studies involving planktonic foraminifera and magnetic stratigraphy in northern South America strata during this time interval. Interpretations of sequence stratigraphy indicate that the sections studied were located in three different basins (northern middle Magdalena, Llanos Foothills, Catatumbo) with three different subsidence histories, sediment sources, and stratal architecture. There are, however, two events that seem to have a regional distribution and probably are related to tectonics and/or eustasy. The first is an early Eocene sequence boundary (SB) that was identified in all three sections (Pinalerita, Regadera, and Uribe) and two additional sections extracted from the literature (Tl and Tibu). The second regional event is an early middle Eocene flooding that was observed in all 5 sections, although in Uribe (northern Middle Magdalena Valley) is highly interpretative (Fig. 626). The Llanos foothill section (Pinalerita) was accumulated in passive-margin basintype, where sediments were derived from the craton. It is composed by two sequences, P.l and P.2 (Fig. 6-15). The late Paleocene to earliest Eocene PI sequence was accumulated in mixed to suspension-load environments of fluvial to coastal plain. PI contains a transgressive systems tract (TST) in the lower 105 m of the Arcillas de El Limbo Formation, and a highstand systems tract (HST) in the upper Arcillas de El Limbo (102-477 m). The lowstand systems tract (LST) of this sequence was not studied. The early to middle Eocene P.2 sequence was accumulated in an incised valley, that contained fluvial bed-load, fluvial suspension-load, and coastal plain to estuarine environments. P.2 is composed of a LST in the first 166 m of the Arcillas de El Limbo Formation, a TST in the upper 71.6 m of Areniscas de El Limbo and lower 10.4 m of the San Fernando Formation, and a HST beginning at 10.4 m of the lower part of San Fernando Formation. An early late Paleocene transgressive surface (TS) was identified at 0 meters (0 composite units, c.u.) based upon an abrupt lithofacies change from bed-load to

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202 suspension-load channels. A middle late Paleocene maximum flooding surface (MFS) was identified at 105 m (105 c.u.) based upon an increase of coastal plain palynomorphs, palynofacies, bioturbation, and change from a transgressive to a regressive pattern. An early early Eocene sequence boundary (SB) was identified at 477m (477 cu) based upon an abrupt change from suspension-channels to load-channels, and a paleosoil. A late early Eocene TS is identified at 643m (596 cu) based on palynofacies, palynomorph paleoecology (dinoflagellates, coastal plain sporomorphs), and bioturbation. Finally, an early middle Eocene TST is identified at 725 m (730 cu) based on palynofacies, and paleoecology (dinoflagellates and coastal plain elements). The topology of these two sequences is similar to that proposed by Cooper et al. (1995) and Cazier et al. (1995) although dating of sequences is different. The Regadera section (Catatumbo area) was accumulated in an area where sediments were derived from Santander massif and craton and prograded northeastward toward Maracaibo Gulf. The section is composed of two sequences, the upper part of sequence R.l and the lower part of sequence R.2, both accumulated in fluvial environments (Fig. 6-16). R.l is composed of a late Paleocene HST in the upper Cuervos Formation. R.2 is composed of a LST in the Mirador Formation (0 to 285.5m), and a few meters of a TST in the lower Carbonera Formation. An earliest Eocene SB (502 c.u.) was identified at 0 meters based upon an abrupt change of suspension to bed-load channels. An early middle Eocene TS is identified a 285.5 m (715 c.u.) based on palynofacies, palynomorph paleoecology (coastal plain taxa) and rapid lithofacies change. The Uribe section (northern Middle Magdalena Valley area) was accumulated in a foreland basin with sediments derived from the Central Cordillera. The section is composed of two sequences, the upper part of sequence U. 1 and the lower part of sequence U.2, both accumulated in fluvial environments (bed-load to mixed load, Fig. 617). U.l is composed of a late Paleocene HST in the upper Catatumbo Formation. R.l is composed of a LST in the La Paz Formation (0 to 1046m), and a few meters of a TST in

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203 the lower Esmeraldas Formation. An earliest Eocene SB (5 10 c.u.) was identified at 0 meters based upon an abrupt change from suspension to bed-load channels. A TS is identified at 1046 meters based on a rapid lithofacies change. This TS could not be dated because of poor recovery of palynomorphs but is probably younger that the middle Eocene TS in the other two sections. From the sequence stratigraphic analysis and biostratigraphy developed here, it is clear that the formation boundaries are not isochronous and do not match epoch boundaries as has been traditionally stated in northern South American geological literature (Fig. 6-27). Therefore, correlations attempted solely on basis of formation nomenclature or lithology are very suspect. Although, in some special cases, some formation boundaries may correspond to time lines. An example of that is the earliest Eocene SB that was found in all sections (Fig. 6-26). Analysis of pollen and spores diversity across the late Paleocene-middle Eocene interval in the Pihalerita section indicates that the early to middle Eocene contains a statistically significant higher diversity than late Paleocene strata (Fig. 7-6a). This pattern is maintained even after sample size, number of sample/time unit, lithofacies and depositional systems, and recovery differences are accounted for. Another clear signal of the pollen record is the extinction of a late Paleocene flora at the end of the Paleocene and its subsequent replacement by a more diverse early to middle Eocene flora (Fig. 7-7b). This extinction occurred in pulses rather than gradually (Fig. 7-6b), and it is suggested that Eocene speciation was also in pulses but the lack of recovery in earliest Eocene strata interval does not allow to confirmed it. A similar extinction/speciation pattern has been found in late Paleocene-Eocene strata from Wyoming (Wing, 1998). This palynoflora pattern could be correlated with climatic conditions during the latest Paleocene and subsequent Eocene Thermal Maximum. The late Paleocene Thermal Maximum (LPTM) produced a fast warming in neotropical areas that could be associated with the plant extinction. The Eocene warming produced slightly cooler temperatures in

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204 the neotropics increasing water -availability that resulted in increased diversity. This suggests that tropical climates fluctuated and exerted pressure on patterns of tropical plant distribution and diversification through geological time. Paleocene and Eocene palynofloras from northern South America had 11% and 1 1.5% similarities respectively with those from tropical Africa (Fig. 7-8). A third part of those shared taxa are coastal plain elements. These taxa appear during the Paleocene or Eocene, indicating that African-South America interchange still was continuing in the Eocene, and did not stop at the end of the Cretaceous or Paleocene as previous authors had suggested (Raven and Axelrod, 1974; Coetzee, 1993; Romero, 1993). An alternative hypothesis is that this shared flora is the result of a late Cretaceous stock that speciated in subtropical areas. Then, these floras migrate toward the tropics during the Paleogene warmings, and consequently appeared for first time in the tropical fossil record. This hypothesis, however, does not have support from the fossil record of subtropical areas during the late Cretaceous. Similarities during the Eocene between northern South America and Central American/Caribbean and Gulf coast palynofloras are relatively low (6.6 and 5.2% respectively) (Fig. 7-8). Paleocene data from the Caribbean are unpublished whereas data from Gulf Coast indicate a 0.7% similarity with northern South America palynofloras. One third of those Eocene shared taxa are coastal plain elements. Migration took place in two opposite directions and was restricted to the Eocene, probably relating to the expansion of tropical zones during the Eocene warming. These two phytogeographic patterns indicate that latitudinal control on the distribution of vegetation was a stronger influence on floristic similarities than proximity of continents, as distance Africa-South America was longer than Caribbean/Gulf Coast-South America during the Paleogene.

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APPENDIX A TAXONOMIC DESCRIPTIONS Palynomorphs (spores, pollen, and dinoflagellates) were categorized in four groups: Pteridophyte spores, Gymnosperm pollen, Angiosperm pollen, and dinoflagellate cysts. Under each category, the fossil genera are arranges in alphabetic order. All the genera treated herein are form-genera as recognized in the "Tokyo Code" (Greuter et al, 1994). Wherever found necessary, new combinations are also discussed, and full synonymies given. Unnamed species are indicated informally by quotation marks. These species are not formally described because a dissertation is not considered a valid publication (Traverse, 1996). All slides are stored at the Paleobotanical collection of Florida Museum of Natural History. Coordinates are measured in Zeiss scope # 2 of the Paleobotanical laboratory of Florida Museum of Natural History. The terminology used for describing sporomorphs (pollen and spores) follows the glossary of pollen/spores terminology developed by University of Utrecht (Punt et al, 1994). The terminology proposed by Evitt (1985) is used for describing dinocysts. Name of the authors and dates of valid publications that follow generic names of pollen and spores are according to Jansonius and Hills (1976, 1985, 1987). Name of the authors and dates of valid publications that follow generic names of dinoflagellate cysts follow Williams et al (1998). Unless actually cited, the publications in which the names first appeared are not listed in "References" list. 205

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206 PTERIDOPHYTE SPORES Genus Baculatisporites Pflug & Thomson in Thomson & Pflug 1953 Baculatisporites "irregularis" Fig. A-l, 1-3 Diagnosis: Baculatrilete, mid-sized (28um), intexine 0.7um thick, margo thin and indistinct, curvatura absent, two sizes of sculptural elements: baculae 2um high, sparsely distributed, and baculae-clavae
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207 Discussion: Hamulatisporis caperatus (Van Hoeken Klinkenberg, 1964) Schrank, 1994 lack interradial crassitude (Schrank, 1994) Genus Chomotriletes Naumova 1939 ex 1953 Chomotriletes minor (Kedves, 1961) Pocock, 1970 Fig. A-l, 10 Diagnosis: Circular, mid-sized (29-45um), trilete mark indistinct, with concentric ridges and grooves. Specimens: PIN 24+60, 17.9 x 86.5 Genus Cicatricosisporites Potonie & Gelletich 1933 Cicatricosisporites dorogensis (Potonie and Gelletich, 1933) Kedves, 1961 Fig. A-l, 11-13 Diagnosis: Cicatricosisporate, trilete, mid-sized (36-58um in proximal view), muri 1.52um wide, 0.5lum high, groove 1.5um wide. Specimens: PIN 28+0, 8.1 x 88.5 Cicatricosisporites dorogensis subsp. minor forv. rugulatearis Kedves, 1961 Fig. A-l, 14-16 Diagnosis: Cicatricosisporate, trilete, mid-sized (50-57um), rugulate to rugulatecicatricosate, muri 2-3um wide, 0.8-1.3um high, groove 1.5-2um wide. Specimens: PIN 28+0, 8.1 x 88.5 Cicatricosisporites "infrafoveolatus" Fig. A-l, 17-19

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208 Diagnosis: Trilete, mid-sized (40um), proximal face laevigate, distal cicatricosate with concentric ridges, intexine lum thick, internally foveolate-micropitted, one grain found Specimens: N 18,4x86.7 Genus Cicatricososporites Pflug & Thomson in Thomson & Pflug 1953, emend. Potonie 1960 Cicatricososporites "decussatus" Fig. A1,20-22 Diagnosis: Monolete, mid-sized (57um), cicatricosate, muri diagonal to laesura, lum wide, 0.5um apart, one grain found Specimens: PIN 55+30, 5.4 x 92.3 Discussion: Cicatricososporites eocenicus (Selling, 1944) Jansonius and Hills, 1987 has ridges parallel to laesura, Cicatricososporites parallatus (Mathur)Awad,1994 has striae almost parallel to striae mark (Awad, 1994). Cicatricososporites eocenicus (Selling, 1944) Jansonius and Hills, 1987 Fig. A-2, 1-2 Diagnosis: Monolete, mid-sized (50-63um), cicatricosate, muri parallel to laesura, 1.52um wide, 0.5lum apart. Specimens: PIN 52+100, 6 x 102.6 PIN 28+0, 17.6 x 1 10 Genus Clavatisporites Kedves & Simoncsics 1964 Clavatisporites mutisi (Van der Hammen, 1954) Jaramillo comb. nov. Fig. A-2, 3-4 Triletes mutisi Van der Hammen, 1954, p. 102, pi. 17. Clavatriletes mutisi (Van der Hammen, 1954) Sarmiento, 1992, p. 63, pi. 1, figs. 1-2. Diagnosis: Clavatrilete, mid-sized (3 lum), intexine 1.5um thick, clavae predominate but

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209 also granules, baculae, and spines all in same grain, 0.5-1.5um high, 0.5-1.5u wide, 0.51 .0.um apart, irregular, densely distributed, one grain found Specimens: N 87, 14.1 x 85.5 Discussion: Clavatriletes Regali et al, 1974 is a junior homonym and possible latter synonym of Clavatriletes Herbst, 1965, Clavatriletes Herbst, 1965 probably is a junior synonym of Clavatisporites Kedves & Simoncsics, 1964 (Jansonius and Hills, 1976, card 521). Genus Echinatisporis Krutzsch 1959 Echinatisporis "brevispinosus" Fig. A-2, 5-6 Diagnosis: Echitriletes, mid-sized (24-36um), intexine lum thick, spines 3-5um high, 1.5-2um wide, ends pointed, uniformly shaped, densely distributed over entire grain, density and height of spines is variable. Specimens: PIN 12, 6.3 x 98.5; RE 132, 21.2 x 90;PIN 81+0, 9.4 x 84.5 Discussion: Echitriletes muelleri Regali et al, 1974 has larger spines (> 6um), wider spaced (6um), and spine tips are highly variable in same grain, Echinatisporis minutus Van der Kaars, 1983 has a trilete mark not always distinct, spines are shorter (<2.5um) and grain is smaller (16-26um) (Van der Kaars, 1983), Echinatisporis "obscurus" has two size-classes of spines, expanded at the base, and margo is indistinct. Echinatisporis? "cingulatus" Fig. A-2, 7-9 Diagnosis: Echitrilete, mid-sized (24-35um), cingulate, cingulum 1.5um thick, contact surface scabrate, remainder of grain echinate, l-3um high, l-2um wide. Specimens: PIN 52+1 10, 7.4 x 81.5

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210 Discussion: Unique combination cingulate-echinate. However, Echinatisporites Krutzsch 1959 is designated for azonotriletes microspores (Jansonius and Hills, 1976). Echinatisporis "microechinatus" Fig. A 2, 10-12 Diagnosis: Trilete, microechinate, mid-sized (27um), intexine thin, 0.5um thick, microspines <0.4u high, 0.7um wide, uniformly and densely distributed. One grain found Specimens: PIN 19+60, 19.1 x 88.2 Discussion: Echinatisporis minimis Van derKaars, 1983 has larger spines 1.5-2. 5um high (Van der Kaars, 1983). Echinatisporis "obscurus" Fig. A-2, 13-15 Diagnosis: Echitrilete, mid-sized (23-34um), intexine 0.5lum thick, trilete mark faint to indistinct, contact area laevigate to scabrate, two size classes: larger spines J-2.5um high, 1.5-4um wide, greatly expanded at the base, smaller spines 0.5um wide/high scattered among the larger spines, density and height of spines are variable. Specimens: N 1 10, 21.2 x 92.1; N 110,3.6x91.9 Discussion: Echinatisporis muelleri (Regali et al. 1974) n. comb, has larger spines (> 6um), wider spaced (6um), and spine tips are highly variable in same grain (Regali et al. 1974), Echinatisporis minimis Van der Kaars, 1983 is smaller (16-26um), and spines are thinner (lum) (Van der Kaars, 1983), Echinatisporis "brevispinosus" has one size-class of spines, not expanded at the base, and margo is distinct, Echinatisporis "portae" has a raised laesura, and intexine is slightly scabrate. Echinatisporis "portae" Fig. A-2, 16-18

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211 Diagnosis: Echitrilete, small-sized (24um), laesura raised and distinct, spines variable in shape and size in same grain, 0.5-2um high, 0.5um-2um wide, fairly distributes, intexine slightly scabrate, one grain found Specimens: PIN 28+0, 5.2 x 87.1 Discussion: Echinatisporis "obscurus" has spines expanded at the base, and margo is indistinct. Genus Foveotriletes Van der Hammen ex Potonie 1956 Foveotriletes "fossulatus" Fig. A-2, 19-22 Diagnosis: Foveotriletes, mid-sized (30-35um), proximal face laevigate, distal face foveolate-fossulate, lumen 2-5um, l-1.5um apart, radii long, margo absent to indistinct. Specimens: PIN 81+0, 12.2 x 1 1 1.8; PIN 52+1 10, 5 x 82.3 Discussion: Crassoretitriletes vanraadshooveni Germeraad et al, 1968 has a coarse reticula over entire grain (Germeraad et al, 1968), Foveotriletes margaritae (Van der Hammen, 1954) Germeraad et al, 1968 has sculpture over entire grain and it larger, 3853um (Germeraad et al, 1968). Foveotriletes margaritae (Van der Hammen, 1954) Germeraad et al, 1968 Fig. A-2, 23-24 Diagnosis: Foveotrilete, mid-sized (40-53um), intexine l-2um thick, foveolae 0.5-2um wide, l-2um part, radii short, laesura inconspicuous, sculpture width and coarseness is variable. Specimens: PIN 63+20, 17.6 x 106 Genus Ischyosporites Balme 1957, emend. Fensome 1987 Ischyosporites "problematicus"

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212 Fig. A-2, 25-28 Diagnosis: Trilete, mid-sized (30-40um), intexine 2um thick, fossulate, fossulae large, with undulating margins, bifurcating, and being connected with each other, 2um wide, 412um long, muri 3-4um wide, coarseness of fossulae is variable. Specimens: N 1 10, 13.9 x 85.6; N 265, 12 x 1 14 Discussion: Other species of Ischyosporites Balme 57, emend. Fensome, 1987 has a shape of lumina is different being circular, polygonal or irregular in shape and generally isolated from each other (Jansonius and Hills, 1976), Reticulatisporites Ibrahim, 1933, emend. Neves, 1964 is cingulate and muri is thinner (Jansonius and Hills, 1976). Genus Kirchheimerisporites Kedves 1995 ex Kedves, hoc loco Kirchheimerisporites "tenuiradiatus" Fig. A-2, 29-30 Diagnosis: Psilatriletes, mid-sized (24-29um), radially oriented internal thickenings, lum wide, 2um long, 0.1-0.3um high. Size (24-29um) Specimens: PIN 55+30, 5.1 x 99.5 Discussion: Kirchheimerisporites khargaensis Kedves, 1995 is larger (40-56um), and has other thickenings around the laesura (Kedves, 1995). Genus Laevigatosporites Ibrahim 1933 Laevigatosporites "barcoi" Fig. A-2, 31-33 Diagnosis: Monolete, mid-sized (33um), granular, granules <0.5um high/wide, irregularly distributed forming patches, intexine 0.4um, one grain found Specimens: NA46, 10 x 108.1

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213 Discussion: Laevigatosporites catanejensis Muller et al. ,1987 has a thicker sporoderm (2.5um), and wider granules, about lum wide (Muller etai, 1987), Laevigatosporites "tenuiexinatus" has a thicker sporoderm (lum), and wider granules (0.5-0.8um). Laevigatosporites "tenuiexinatus" Fig. A-3, 1-3 Diagnosis: Monolete, mid-sized (50um), granular, granules <0.6um high, 0.5-0.8 wide, irregularly distributed forming patches, intexine lum, one grain found Specimens: PIN 28+0, 15.5 x 93 Discussion: Laevigatosporites catanejensis Muller et al. 1987 has a thicker sporoderm (2.5um), and wider granules, about lum wide (Muller et al. 1987), Laevigatosporites "barcoi" has a thinner sporoderm (0.4um), and more narrow granules (<0.5um wide). Laevigatosporites tibui (Van der Hammen 1956) Jaramillo comb. nov. Fig. A-3, 4 Psilamonoletes tibui Van der Hammen, 1956, p. 108, pi. 2, fig. 6. Diagnosis: Monolete, mid-sized (30-50um), elliptic, plane-convex to reniform, laevigate, sporoderm 0.5lum thick, margo indistinct to slightly distinct. Specimens: N 21+100, 6.6 x 91.1 Discussion: Srivastava (1971) considers Psilamonoletes Van der Hammen, 1956 a junior synonym of Laevigatosporites Ibrahim 1933, emend. Schopf, Wilson et Bentall 1944. Genus Microfoveolatosporis Krutzsch 1959 Microfoveolatosporis skottsbergii (Selling, 1946) Srivastava, 1971 Fig. A-3, 5-6 Diagnosis: Foveomonolete, large-sized (60-89 urn), foveolae 1.2-2 wide, lum deep, 1-

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2.4 1 .5um apart, circular, uniform, densely distributed. Specimens: PIN 81+0, 13.2 x 1 12; RE 67+120, 6.8 x 92.3 Genus Osmundacidites Couper 1953, emend. Norris 1986 Osmundacidites "dispergatus" Fig. A-3, 7-9 Diagnosis: Monolete, mid-sized (30um), granular, granules l-2um wide, <0.5um high, sparsely and unevenly distributed, one grain found Specimens: N 18, 7.9 x 105 Discussion: Osmundacidites wellmanii Couper, 1953 is larger (40-63um wide), and exine thicker, 1.5um (Kedves, 1995), Osmundacidites "minor" is densely granular. Osmundacidites "minor" Fig. A-3, 10-12 Diagnosis: Trilete, mid-sized (25-30um), amb circular, intexine l.Oum, granular, granules densely distributed, radii long, laesura simple. Specimens: PIN 63+20, 14.8 x 87.4 Discussion: Osmundacidites wellmanii Couper 1953 is larger (40-63um wide), and exine thicker, 1.5um (Kedves, 1995), Hydrosporis farafraensis Kedves 1995 is two layered (Kedves, 1995). Genus Polypodiaceoisporites Potonie 1951 ex Potonie 1956 Polypodiaceoisporitesl "fossulatus" Fig. A-3, 13-16 Diagnosis: Trilete, mid-sized (33-46um), cingulate, laesura simple, proximal face verrucate or granular, distal face fossulate, sometimes kyrtomate, great variation in

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215 coarseness and density of sculptural elements in proximal and distal faces, kyrtome sometimes developed. Specimens: NA 46, 10.5 x 107.2; La Paz 886m, 20.7 x 88.5; UR 812, 5.3 x 97; PIN 75+160, 5.5 x 79.1; PIN 52+110, 6.7 x 1 12 Discussion: The genus Polypodiaceoisporites Potonie 1951 ex Potonie 1956 is very similar but has a reticulate distal face (Jansonius and Hills, 1976). Genus Polypodiisporites Potonie 1931 ? in Potonie and Gelletich 1933 ex Potonie 1956, emend. Khan & Martin 1972 Polypodiisporites "brevis" Fig. A-3, 17-18 Diagnosis: Monolete, ellipsoid, mid-sized (26-35um), verrucate, 2-2. 5um wide, l-2um high, rounded in plain view, flat, rounded and/or even baculae-like in cross section, rather scattered and variable spaced. Specimens: UR 531+120, 14.8 x 110.7; UR 761, 20x87 Discussion: Verrucatosporites usmensis (Van der Hammen 1956) Germeraad et al. 1968 is larger (39-6 lum), and has gemmae that are more widely and variable spaced (Germeraad et al, 1968), Polypodiisporites specious Sah 1967 is larger (36-60um), and proximal face is laevigate (Sah, 1967), Verrucatosporites "protousmensis" .is larger (3050um), and verjucae polygonal with sharp vertices. Polypodiisporites "breviverrucatus" Fig. A-3, 19-21 Diagnosis: Monolete, reniform, mid-sized (48-60um), proximal face scabrate, distal verrucate, verrucae flat,<0.3um high, forming a negative reticula. Specimens: La Paz 712m, 17.6 x 106.5

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216 Discussion: Polypodiisporites specious Sah 1967 has higher verrucae (0.5-2um high) (Sah, 1967) Verrucatosporites usmensis (Van der Hammen 1956) Germeraad et al, 1968 is gemmate (Germeraad et al, 1968). Polypodiisporites "densus" Fig. A-3, 22-24 Diagnosis: Monolete, ellipsoid, mid-sized (42-43um), gemmate, gemmae 2-5um wide, 24um high, globular to mushroom-like, densely distributed, diminishing around laesura height of sculpture is variable. Specimens: PIN 81+0, 16.6 x 90 Discussion: Verrucatosporites usmensis (Van der Hammen, 1956) Germeraad et al, 1968 has gemmae shorter (1.5-2.5um high), more widely and variable spaced (Germeraad etai, 1968). Polypodiisporites "echinatus" Fig. A-4, 1-3 Diagnosis: Monolete, plane-convex, mid-sized (30-43um), echinate, spines 4-8um wide, 2-5um high, 2-5um apart, irregularly shaped, size and density of sculpture are variable. Specimens: N 74, 15.5 x 108.5 Discussion: spiny sculpture has not been reported in other species of Polypodiisporites. Polypodiisporites "pachyexinatus" Fig. A-4, 4-6 Diagnosis: Monolete, mid-sized (39-48um), thick intexine 3um thick, proximal face laevigate, distal verrucate, verrucae flat,<0.5um high, verrucae 2-5um wide, fairly and irregularly distributed, interverrucae wall scabrate. Specimens: N 174, 8.2 x 92

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217 Discussion: Polypodiisporites specious Sah, 1967 has higher verrucae (0.5-2um high), densely distributed (Sah, 1967), Verrucatosporites usmensis (Van der Hammen, 1956) Germeraad et al, 1968 is gemmate (Germeraad et al, 1968). Polypodiisporites "protousmensis" Fig. A-4, 7-8 Diagnosis: Monolete, plane-convex, mid-sized (30-50um), verrucate, 2-5um wide, 0.51.2 apart, polygonal with sharp vertices, irregularly shaped and distributed, also with scattered baculae and gemmae, sculpturing has a very distinct dark color that contrast with light color of intexine, size and coarseness of sculpture are variable. Specimens: N 21+100, 1 1.6 x 98.8 Discussion: Polypodiisporites specious Sah 1967 has a proximal face laevigate, verrucae has rounded vertices, and lack gemmae or baculae (Sah, 1967), Verrucatosporites usmensis (Van der Hammen, 1956) Germeraad et al. ,1968 is gemmate (Germeraad et al, 1968) Polypodiisporites specious Sah, 1967 Fig. A-4, 9-10 Diagnosis: Monolete, reniform, mid-sized (36-60um), proximal face laevigate, distal verrucate, verrucae irregular in shape and size, l-4um wide, 0.5-2um high, 0.5-1.5 apart, size and coarseness of sculpture is variable. Specimens: PIN 75+160, 10.2x78.8 Genus Pteridacidites Sah 1967 Pteridacidites "cucutensis" Fig. A-4, 11-13

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218 Diagnosis: Trilete, mid-sized (40um), cingulate, laesura simple, proximal face laevigate, distal face verrucate, few verrucae very large, isolated or fussed at the base. Specimens: La Paz 712m, 15 x 88.4; La Paz 886m, 8.2 x 78.3 Discussion: Pteridacidites africanus Sah 1967 is larger (60-80um), and verrucae occur in proximal face (Sah, 1967). Genus Retitriletes Pierce 1961 Retitriletes "enigmaticus" Fig. A-4, 14-16 Diagnosis: Trilete, circular, mid-sized (40-60um), entire body reticulate, lumina 5-7um wide, hexagonal, muri thin, 2um high produced by a rise of exoexine. Specimens: PIN 66+80, 5.5 x 84.2 Discussion: Zlivisporis blanensis Pacltova 1961 has proximal face laevigate (Pacltova, 1961). Here, I follow the opinion of Krutzsch 1963 that consider Lycopodiumsporites a nomen dubium, and suggest that all reticulate lycopodiaceoid tertiary forms should be assigned to Retititriletes Pierce 1961 (In Jansonius and Hills, 1976). Genus Tuberositriletes Doring 1964 Tuberositriletesl "inciertus" Fig. A-4, 17-19 Diagnosis: Trilete, mid-sized (26um), intexine lum, verrucate, verrucae 0.5um high, circular, rounded or flat tip, widely and irregularly spaced, one grain found Specimens: N 354+120, 15 x 107.7 Discussion: Tentatively is placed in Tuberositriletes Doring, 1964 although the amb is circular rather than triangular, and verrucae density is lower than type species, and verrucae density is lower than type species.

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219 Tuberositriletes "verrucatus" Fig. A-4, 20-22 Diagnosis: Trilete, mid-sized (27-32um), intexine lum, verrucate, verrucae large, 2um high, well rounded in cross section, relatively even in shape and size, densely distributed over entire body. Specimens: PIN 12, 10x94.9 Discussion: Tuberositriletes? "inciertus" has smaller verrucae (0.5um high), more widely distributed, Distaverrusporites Muller, 1968 has proximal face laevigate (Muller, 1968). Genus Zlivisporis Pacltova 1964 Zlivisporis blanensis Pacltova, 1961 Fig. A-4, 23-24 Diagnosis: Trilete, circular, mid-sized (45-60um), proximal face laevigate, distal reticulate, lumina wide, hexagonal, muri thin, produced by a rise of exoexine. Specimens: N 120, 18.3 x 95.4 GYMNOSPERM POLLEN Genus Araucariacites Cookson and Couper 1953 Araucariacites "rugulatus" Fig. A 5, 1-3 Diagnosis: Inaperturate, large-sized (66um), ellipsoidal, intectate 1.2um thick, rugulate, rugulae lum wide, 3-5um long, 0.2um high, one grain found. Specimens: N 149, 1 1.3 x 92.5 Discussion: Araucariacites australis Cookson, 1947 is thinner in poles and has a microrugulate to granular sculpture.

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220 Araucariacites "scabratus" Fig. A 5, 4-5 Diagnosis: Inaperturate, mid to large-sized (40-70um), intectate very thin 0.5um thick, densely scabrate.. Specimens: N 74, 14.5 x 104.7 Discussion: Inaperturopollenites cursis Sarmiento, 1992 is smaller and reticulate Sarmiento, 1992), Araucariacites australis Cookson, 1947 has a thicker exine (l-3um) and is commonly thinner in poles. Genus Ephedripites Bolkhovitina 1953 ex Potonie 1958 Ephedripites vanegensis Van der Hammen and Garcia, 1 966 Fig. A 5, 6 Diagnosis: Inaperturate, polyplicate, mid-sized (35-40um), atectale 0.8um thick, thicker at polar areas (1.2um), with a smooth zone at each pole of about 3-6um, 18-35 plicae. Specimens: NA 59+90, 4.9 x 86.7; NA 46, 15.5 x 107 Genus Laevigatasporites Potonie and Gelletich 1933 Laevigatasporites "laevigatus" Fig. A-5, 7-8 Diagnosis: Inaperturate, large-sized (85-120um), elliptic, psilate grain with atectate exine 1 to 1.9um thick. Specimens: N 87, 8x81.5 Discussion: Araucariacites australis Cookson, 1947 is commonly thinner in poles and has a microrugulate to granular sculpture. ANGIOSPERM POLLEN Genus Aglaoreidia Erdtman 1960

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221 Aglaoreidia? "foveolatus" Fig. A-5,9-11 Diagnosis: Monoporate, medium sized (42-43um), foveoreticulate, shape straight-convex, pore large, costate, exine 2um thick decreasing near poles, foveolate, foveolae 2um wide at equator gradually diminishing near poles. Specimens: N 45, 14 x 111.2 N 45, 17.9x90.1 Discussion: Aglaoreidia Erdtman 1960 is the most similar genus although it is reticulate and lumina increase near pore except in the immediate vicinity of the pore (Jansonius and Hills, 1976). Genus Anacolosidites Cookson and Pike, 1954, emend. Potonie 1960 Anacolosidites ariani (Sarmiento, 1992) Jaramillo comb. nov. Fig. A-5, 12-13 Duplotriporites ariani Sarmiento, 1992, p. 88, pi 12, figs. 1-2. Diagnosis: Periporate, mid to large-sized (55-65um), six pores arranged in two triplets, symmetrically located in both sides of the equatorial plane, annulate, baculae fairly distributed, 24um high, microbaculae 0.7-0.8um high, densely distributed. Specimens: UR 531+120, 14.6x1 14.6; La Paz 712m, 16.9 x 103.8 Discussion: Duplotriporites Sarmiento 1992 is considered here a junior synonym of Anacolosidites Cookson & Pike 1954. There is not a unique characteristic separating Duplotriporites from Anacolosidites. Genus Baculamonocolpites Sole de Porta, 1971 Baculamonocolpites "angustus" Fig. A-5, 14-15

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222 Diagnosis: Monosulcate, mid-sized (33um), marginate margo 3um wide, baculate, baculae 1.5 high, l-2um wide, sparsely distributed over the surface, base slightly wider than tip. Tectum interbaculate is micropitted to scabrate", One grain found Specimens: UR 761 7.4 X 97.9 Discussion: Baculamonocolpites multispinosus (Van der Hammen) Sole de Porta, 1971 is smaller (40-43 urn), has thinner exine, and shorter baculae (Sole de Porta, 1971), Bacumorphomonocolpites tausae Sole de Porta, 1971 has larger and bifurcation baculae, Racemonocolpites Gonzalez 1967 has a higher baculae. Baculamonocolpites "bimodalis" Fig. A-5, 16-18 Diagnosis: Monosulcate, colpus indistinct, mid-sized (40um), two sculptural elements: baculae (2-4urn high) and scabrae-microbaculae in the tectum interbaculae (<0.9um high), tectate, columellae indistinct, one grain found, Specimens: PIN 32, 7 x 98 Discussion: Echimorphomonocolpites Gonzalez 1967 has a dominant echinate sculptural element, other Baculamonocolpites species do not have two types of sculptural elements (baculate and scabrate microbaculate). Baculamonocolpites "curubensis" Fig. A-5, 19-22 Diagnosis: Baculamonosulcate, mid to large-sized (50-65um), intectate 2um thick, baculae 4-5um high, slightly wider at the tip, densely distributed, exine psilate in interbaculate areas, variable in density of baculae, from sparsely to densely distributed. Specimens: PIN 52+1 10 6.6x97.1; PIN 32+0, 9.6 x 90.5 Discussion: Racemonocolpites Gonzalez 1967 have a predominant gemmate sculpture more densely distributed, Baculamonocolpites multispinosus (Van der Hammen) Sole de

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223 Porta 1971 is smaller (40-43 um), nexine is thinner (lum), and baculae is sparsely distributed and not constrict (Sole de Porta, 1971). Genus Bacumorphomonocolpites Sole de Porta, 1971 Bacumorphomonocolpites tausae Sole de Porta, 1971 Fig. A-5, 23-24 Diagnosis: Monosulcate, large-sized (90um), ellipsoidal, atectate (2um thick), baculate 220um long in same grain, longest baculae branches apically, one grain found. Specimens: UR 502, 1 1.8 x 97.1 Genus Bacutriporites Jan du Chene, Onyike, and Sowunmi 1978 Bacutriporites "echinatus", Fig. A-5, 25-26 Diagnosis: Bacutriporate, triangular-obtuse-convex, baculate to echinate, 4um high, 2um wide, tip always rounded. Tectum interbaculate is slightly scabrate, one grain found. Specimens: PIN 42+100, 21.9x88.9 Discussion: Unique in combination of aperture and sculpture, Echitriporites trianguliformis Van Hoeken Klinkenberg, 1964 is smaller and has shorter spines. Genus Bombacacidites Couper 1960, emend. Krutzsch 1970 Bombacacidites annae (Van der Hammen, 1954) Germeraad et ai, 1968 Fig. A-6, 1-3 Diagnosis: Bombacacidites-type, mid-sized (25-50um), triangular-obtuse-convex, reticulate, muri pluricolumellate, lumina 1-3 wide in apocolpia and around colpi, diminishing toward mesocolpia, size and coarseness of reticulum is variable.

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224 Specimens: N 21+100, 22.5x86.8; NA 59+90, 9.5 x 104.9; N 18, 5.5. x 83.4 N 1 10, 8 x 99.7 Bombacacidites brevis (Duenas, 1980) Muller etal, 1987 Fig. A-6, 4 Diagnosis: Bombacacidites-type, mid-sized (26-40um), triangular-obtuse-convex to circular, thin costae, reticulate, lumina constant over the entire grain, 0.8-0.9um, circular. Specimens: PIN 28+0, 15.2 x 96.8; PIN 35+90, 5.9 x 80; PIN 63+20, 7.3 x 1 1 1; PIN 52+110, 16.6 x 112.1. Bombacacidites "caldensis" Fig. A-6, 5-7 Diagnosis: Bombacacidites-type, mid-sized (45um), elliptic, costae thin 1.2um wide, pores distinct, reticulate, lumina constant over the entire grain, 0.8lum wide, one grain found. Specimens: NA46, 7.9 x 84.5 Discussion: Bombacacidites brevis (Duenas, 1980) Muller et al. 1987 is smaller (<40um), pores are indistinct, and margo is thinner (
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225 Discussion: Differ from other Bombacacidites in its fossulate-psilate sculpture and the mesocolpia nexine thickenings. Bombacacidites "etayoi" Fig. A-6, 11-12 Diagnosis: Bombacacidites-type, mid-sized (33-40um), triangular-obtuse-straight, exine thin (0.7lum), costae l-2um wide, reticulate, lumina 0.5-0.8um at apocolpia to 0.5um at mesocolpia, transition is extremely gradual, lumina diameter at the apocolpium is variable. Specimens: N110, 7.3 x 109.1 N149, 4.5 x 89.5 Discussion: Bombacacidites nacimientoensis (Anderson I960) Elsik 1968 has a larger lumina, 2-4um wide (Elsik, 1968b), Bombacacidites brevis (Duenas, 1980) Muller et al, 1987 has uniform lumina, narrower margo (0.8-lum), and triangular-obtuse-convex to circular shape (Muller et al, 1968). Bombacacidites "fossureticulatus" Fig. A-6, 13-14 Diagnosis: Bombacacidites-lypc, small to mid-sized (21-30um), triangular-obtusestraight, fossulate at apocolpia and colpi margins to reticulate in mesocolpia. Specimens: PIN 28+0, 13 x 98.5; PIN 28+0, 14 x 1 12 Discussion: Bombacacidites foveoreticulatus Muller et al, 1987 has a shorter colpi, thicker exine, larger lumina, and is foveoreticulate, Bombacacidites "protofoveoreticulatus" has a fossulate-foveolate lumina that is constant over entire grain. Bombacacidites foveoreticulatus Muller et al, 1987 Fig. A-6, 15-16

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226 Diagnosis: Bombacacidites-lype, mid-sized (35um), triangular-obtuse-straight, costae 3um wide, fossulate at apocolpia and colpi margins to reticulate at mesocolpia, one grain found Specimens: PIN 81+0, 1 1.8 x 98.1 Bombacacidites "gentryi" Fig. A-6, 17-19 Diagnosis: Bombacacidites-type, mid-sized (40um), circular, costae very thin, reticulatefoveolate at the apocolpia, 0.7um wide, grading to a more wider lumina at mesocolpia, 22.5um wide, one grain found. Specimens: PIN 81, 4.6x87 Discussion: Unique Bombacacidites in having lumina of reticulum grading from foveolate at apocolpia to reticulate at mesocolpia. Intratriporopollenites Pflug & Thomson in Thomson & Pflug 1953 is vestibulate (Jansonius and Hills, 1976). Bombacacidites nacimientoensis (Anderson, 1960) Elsik, 1968 Fig. A-6, 20-21 Bombacacidites nacimientoensis Anderson, 1960, p. 23, pi. 18, fig. 13. Bombacacidites nacimientoensis (Anderson, 1960) Elsik, 1968b, p. 620, pi. 22, figs. 1-2, 4. Bombacacidites bellus Frederiksen 1980 Muller etal. ,1987, p. 45, pi. 4, fig. 5 (nomen nudum) Diagnosis: Bombacacidites-type, mid-sized (31-50um), triangular-obtuse-straight, reticulate, muri pluricolumellate, lumina 2-4m wide in apocolpia and around colpi, diminishing toward mesocolpia, transition although gradual, occurs in a narrow zone surrounding each angle of the grain. Specimens: PIN 28, 18.6 x 100.3; PIN 12, 10.4 x 103

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227 Discussion: Bombacacidites annae (Van der Hammen 1954) Germeraad et al 1968 has a triangular-obtuse-convex shape, a shorter colpi, and a wider costa (3um). Bombacacidites "simplireticulensis" has a simplicolumellate muri. Bombacacidites "nissoides" Fig. A-6, 24-26 Diagnosis: Bombacacidites-type, mid-sized (46um), triangular-obtuse-convex., costae 3um wide, reticulate, lumina lum wide constant over the entire grain, one grain found. Specimens: PIN 63+20, 21 x 109.9 Discussion: Bombacacidites brevis (Duenas, 1980) Muller et al. 1987 is smaller (<40um) and margo is thinner ,
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228 Discussion: Bombacacidites ciriloensis Muller et al. 1987 has a muri pluricolumellate and a shorter colpi (CIp:0.3), Bombacacidites brevis (Duenas, 1980) Muller et al 1987 has a narrower lumina (0.8-0.9um), Bombacacidites "nissoides" has a narrower lumina (lum). Bombacacidites "protofoveoreticulatus" Fig. A-7, 1-6 Diagnosis: Bombacacidites-typc, mid-sized (30-40um), triangular-obtuse-convex, costae 3um wide, fossulate-foveolate over the entire grain. Specimens: NA 46, 10.8 x 108.4; N 27, 8 x 98.9; N 27, 20 x 89.3; N 1 10, 18.3 x 95 Discussion: Bombacacidites foveoreticulatus Muller et al. ,1987 is foveolate-reticulate, and has a thicker exine (3um), Bombacacidites "fossureticulatus" is fossulate at apocolpia and colpi margins to reticulate at mesocolpia. Bombacacidites "psilatus" Fig. A-7, 7-9 Diagnosis: Bombacacidites-typc, mid-sized (26-32um), triangular-obtuse-convex to straight, costae 1.5um wide, finely reticulate at apocolpium, lumina 0.8um wide decreasing gradually toward mesocolpia where is micropitted-psilate, coarseness of sculpture is variable. Specimens: RE 67+120, 18.5 x 110; UR 781+20, 16.7 x 90.8; UR 761, 11.4x97.4 Discussion: Bombacacidites brevis (Duenas, 1980) Muller et al. 1987 is more circular and has a larger lumina (0.8-0.9) constant over entire grain (Muller et al., 1987), Bombacacidites "sabanensis" has a slightly protruding costae, lumina decrease abruptly, and it is larger (30-50um).

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229 Bombacacidites "sabanensis" Fig. A-7, 10-12 Diagnosis: Bombacacidites-lype, mid-sized (30-50um), triangular-obtuse-straight, slightly protruding costae, reticulate at apocolpia and surrounding the colpi, lumina 0.8 wide, changing rather abruptly to psilate forming a triangle which vertices are 60 degrees offset. Specimens: PIN 81+0, 14 x 91.4; PIN 52+1 10, 3.3. x 1 13 Discussion: Bombacacidites "psilatus" has a non-protruding costae, lumina decrease gradually, and it is smaller (26-32um). Bombacacidites "simplireticulensis", Fig. A-7, 13-14 Diagnosis: Bombacacidites-type, mid-sized (37-52um), triangular-obtusestraight, colpi very short (CIp:0.1), costae 2-4um wide, reticulate, lumina 2-4 um wide, at vertices of grain sculpture abruptly changes to foveolate (lumina 0.5 wide) or psilate, simplicolumellate. Specimens: PIN 28+0, 12 x 95; La Paz 886m, 10.7 x 103.5 Discussion: Bombacacidites nacimientoensis (Anderson 1960) Elsik 1968 has a longer colpi (CIp:0.45), narrower costae (2um), and a pluricolumellate muri (Elsik, 1968b), Bombacacidites "protonacimientoensis" has a narrower lumina (2um wide) that gradually diminishes to l.lum toward mesocolpia, pluricolumellate. Genus Brevitricolpites Gonzalez 1967 Brevitricolpites "macroexinatus" Fig. A-7, 17-19 Diagnosis: Brevitricolporate, mid-sized (36um), echinate, spines long (3um), micropitted, exine tectate thickening around pores and underneath spines, one grain found

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230 Specimens: PIN 81+0, 19.2 x 83.5 Discussion: Brevitricolpites "microechinatus" is intectate, Brevitricolpites "scabratus" has spines smaller (
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Fig. A-8, 4-6 Diagnosis: Clavamonosulcate, mid-sized (42-45um), thick exine 2um, tectate, sulcus costate, clavae 2um high, scabrae interclavae. Specimens: PIN 71+0, 7.5 x 83.8 Discussion: Differ from other Clavamonocolpites in the clavate-scabrate sculpture. Genus Clavatricolpites Pierce, 1961 Clavatricolpites "densoclavatus" Fig. A-8, 7-10 Diagnosis: Tricolpate, mid-sized (26-42um in polar view), short clavae, densely arranged in rows, or pseudocroton, or random pattern, intectate, nexine 0.8um, 3-5 colpate. Specimens: PIN 28+0, 4.2 x 88.2; PIN 42+100, 19.6 x 107.5; PIN 81+0, 12.5 x 80; PIN 42+100, 10.6x91; RE 67+120, 13 x 104.5; PIN 52+100, 15 x 111.6 Discussion: Clavatricolpites gracilis Gonzalez, 1987 is marginate, Crototricolpites "protoannemariae" has a well defined croton pattern, Crototricolpites americanus Wijmstra, 1971 has acolumellae digitate (Wijmstra, 1971). Genus Colombipollis Sarmiento, 1992 Colombipollis tropicalis Sarmiento, 1992 Fig. A-8, 1 1 Specimens: N 74, 10.2 x 88.8 Genus Cricotriporites Leidelmeyer, 1966 Cricotriporites guianensis Leidelmeyer, 1966 Fig. A-8, 12-13 Cricotriporites operculatus Van Hoeken Klinkenberg, 1966, p. 39, pi. 1, fig. 16 Cricotriporites guianensis Leidelmeyer, 1966, p. 54, pi 4, fig. 4

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232 Diagnosis: Psilatriporate, ellipsoid, small to mid-szed (24-32um), tectate (lum), pores costate, circular, occasionally operculate, operculum sometimes absent, psilate to finely scabrate. Specimens: RE 67+120, 19 x 1 1 1.9 Discussion: No distinct morphological differences between C. guianensis and C. operculums holotypes were found after examination of both holotypes at the Amsterdam collection., Cricotriporites "macropori" Fig. A-8, 14-17 Diagnosis: Psilatriporate, ellipsoid, mid-sized (30-50um), intectate (0.5um), pores annulate (2um wide), circular (5-9um), micropitted, psilate or scabrate. Specimens: PIN 12, 17 x 91; PIN 75+160, 14.6 x 96.9; RE 67+120, 18 x 101.1; PIN 55+30, 13 x 105.7 Discussion: Muller 1968 uses genus Triorites for psilate, atectate triporates accepting the Couper description for the genus while rejecting the emendation of Potonie, 1960a. However, he does not consider the genus Cricotriporites Leidelmeyer, 1966. Here I accept the Potonie emendation for Triorites (In Jansonius and Hills, 1976) consequently using Cricotriporites for circular, finely scabrate-psilate-micropitted triporate grains. Triorites minutipori Muller 1968 is smaller (<30um) and pore width is smaller (<2um), T. festatus Muller 1968 has a smaller pore (3um in diameter), T. tenuiaxis Muller 1968 has a 3-4um high collar. Cricotriporites guianensis Leidelmeyer, 1966 is smaller, and has a thicker exine ( l-2um). Cricotriporites minutipori (Muller, 1968) Jaramillo comb. nov. Fig. A-8, 18 Triorites minutipori Muller, 1968, p. 14, pi. 3, fig. 9.

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233 Diagnosis: Psilatriporate, small tO mid-sized (<30um), atectate, exine very thin (<0.5um), pores costate, <2um in diameter, psilate to finely scabrate. Specimens: PIN 42+100, 7.1 x 82.5 Discussion: Triorites Erdtman 1947 ex Cookson 1950 emend. Potonie 1960 has a 4layered exine (Jansonius and Hills, 1976). Cricotriporites "porielongatus" Fig. A-8, 19-21 Diagnosis: Psilatriporate, ellipsoid, mid-sized (26-35um), atectate (lum), pores annulate, lalongate (6-8um). Specimens: PIN 63+20, 10.9 x 1 10; PIN 55+30, 16.3 X 1 13 Discussion: Cricotriporites "macropori" is larger, has circular pores, a thinner exine, Triorites minutipori Muller, 1968 is smaller, T.festatus Muller 1968 has a smaller pore (3um in diameter), T. tenuiaxis Muller, 1968 has a 3-4um high collar, Cricotriporites guianensis Leidelmeye,r 1966 is smaller, and has a smaller pore (2.5 by 2um). Genus Crototricolp ites Leidelmeyer, 1966 Crototricolpites cf. annemariae Leidelmeyer, 1966 Fig. A-8, 22 Diagnosis: Tricolpate, mid-sized (48um), colpi simple, intectate 0.7um thick, clavate arranged in a croton pattern, clavae 1 .5-2um high, one grain found. Specimens: UR 531+120, 20.6 x 1 1 1 Discussion: The only difference with Crototricolpites annemariae Leidelmeyer, 1966 is that it has a slightly larger clavae (2-3um high). Genus Ctenolophonidites Van Hoeken Klinkenberg,1966 Ctenolophonidites "cruciatus"

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234 Fig. A-8, 25-26 Diagnosis: Ctenolophonidites, 4-colpate, mid-sized (50um), psilate, and with a cross-like ridge, one grain found Specimens: PIN 28+0, 18.4 x 1 1 1.5 Discussion: Ctenolophonidites costatus (Van Hoeken-Klinkenberg, 1964) Van HoekenKlinkenberg, 1966 is 6-colpate and has a ring-like ridge (Van Hoken-Klinkenber, 1966), Ctenolophonidites lisamae (Van der Hammen and Garcia, 1966) Germeraad et al,. 1968 is smaller (17-31 um) and scabrate (Germeraad et al., 1968). Genus Curvimonocolpites Leidelmeyer 1966 Curvimonocolpites inornatus Leidelmeyer, 1966 Fig. A-8, 27 Diagnosis: Monosulcate, mid-sized (29-35um) concave-convex shape in polar view, tectate, psilate. Specimens: N4, 13.3 x 101. Genus Cyclusphaera Elsik, 1966 Cyclusphaera "scabratus Fig. A-9, 1-2 Diagnosis: Its affinities are uncertain, elliptic grain, mid-sized (25-60um), two symmetric large openings lined by a thickening of the grain wall, scabrate-verrucate, tendency upsection in increasing the range of grain size toward larger sizes, also there is a trend in reducing size of sculpturing toward a fine scabrate, and reducing width of thickening lining aperture. Specimens: N354+120, 5.9 x 89.2; PIN 81+0, 3.6 x 1 13

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235 Discussion: Cyclusphaera euribei Elsik, 1966 does not exhibit a thickening of the wall surrounding the aperture, the wall is psilate, and openings are wider, Cyclusphaera doubingeri Salard-Cheboldaeff, 1978 is reticulate/perforate. Genus Echimonocolpites Van der Hammen and Garcia, 1965 Echimonocolpites "tenuiechinatus" Fig. A-9, 3-4 Diagnosis: Monosulcate, small to mid-sized (24-35um), sulcus long, exine reticulate, echinate, small elongate conical spines, spines size 2.5-3.5um high, 0.3-0.5 urn wide. Specimens: N 74, 11 x 103 Discussion: Mauritiidites franciscoi Van der Hammen and Garcia, 1966 has spines that are inserted in the tectum producing depressions in the exine, Spinizcnocolpites Muller 1968, emend. Muller et al. 1987 has a zonocolpus (Muller et al, 1987). Genus Echipericolpites Van der Hammen and Garcia, 1965 Echipericolpites "brevicolpatus" Fig. A-9, 5-7 Diagnosis: Pericolpate, mid-sized (27um), intectate, echinate, spines l-1.5um high, surface interechinate micropitted, one grain found. Specimens: N 120, 16.1 x 111.8 Discussion: Unique pollen grain in being echinate and pericolpate. Genus Echiperiporites Van der Hammen and Wijmstra 1964, emend. Anzotegui 1996 Echiperiporites "scabratus" Fig. A-9, 10-13

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236 Diagnosis: Echiperiporate, large-sized (90um), pores annulate, large spines, 3-4um high, tectum scabrate, only one grain found. Specimens: N 21+100, 12.1 x 110 Discussion: Echiperiporites estelae Germeraad et al. ,1968 has a micropitted tectum, and a smaller size (45-60um). Echiperiporites estelae Germeraad et al., 1968 Fig. A-9, 8-9 Diagnosis: Echiperiporate, mid-sizeD (45-60um), exine 1 .6um thick, tectate, spines 47um tall, tectum interechinate micropitted, great variability in structure of exine (sometimes nexine is thicker), and spines dimensions and density, as well as pore density. Specimens: PIN 28+0, 5.2 x 80.5 RE 251+30, 18.9 x 96.1 Genus Echitetracolpites Song, Qian and Zheng in Qian Zeshu, Zheng Yahui and Song Zhichen, 1993 Echitetracolpites "echinatus" Fig. A-9, 14-15 Diagnosis: Stephanocolporate, mid-sized (30-40um), exine 1.5um, colpi very short, echinate, spines long, 2um high, tectum interechinate is micropitted. Specimens: PIN 28+0, 18.9 x 105.5 Discussion: Echitetracolpites "tenuiexinatus" has a thinner exine (0.8um), two classes of spinae, and colpi less distinct, Echitetracolpites jiangsuensis Song et al. 1993 (in Qian Zeshu et al. 1993) is colpate (Jansonius and Hills, 1976). Echitetracolpites "tenuiexinatus" Fig. A-9, 16-18

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237 Diagnosis: Stephanocolporate, mid-sized (35-50um), exine thin 0.5-0.8um, colpi very short, echinate, two groups of spinae, a large 1.3-2um high, and a small, 0.5-0.8um high, tectum interechinate is micropitted, variability in the length of the colpi, frequently being indistinct. Specimens: PIN 52+100, 4.7 x 94.5; PIN 42+100, 15.7x104.5; PIN 42+100, 18.3 x 85 Discussion: Echitetracolpites "echinatus" has a thicker exine (1.5um), only one class of spinae, diameter of micropitting is larger, costae are better developed, and colpi are more distinctive, Echitetracolpites jiangsuensis Song et al, 1993 (in Qian Zeshu et al, 1993) is colpate (Jansonius and Hills, 1976). Genus Echitricolpites Regali et al, 1974 Echitricolpites "linearis" Fig. A-9, 19-21 Diagnosis: Echitricolpate, mid-sized (50-60um), prolate, tectate, thin exine 0.7um thick, colpi costate, intruding, lined by a row of spines, spines arranged in longitudinal rows 56um apart, spines 0.8um high, tectum micropitted. Specimens: N 1 10, 4.1 x 82.3 N 120, 15 x 109 Discussion: Cristaecolpites echinatus Schrank,1994 is smaller (33um), with two colpuslike furrows, and spines longer (15-2.5um high). Genus Echitriporites Van der Hammen, 1956b ex Van Hoeken Klinkenberg, 1964 Echitriporites "annulatus" Fig. A-9, 22-23 Diagnosis: Echitriporate, mid-sized (29um), pores costate, costae 2um wide, tectate, exine l.lum, spines small, 0.8um high, fairly distributed over the entire grain, one grain found. Specimens: PIN 55+30, 7 x 91.5

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238 Discussion: Echibrevitricolporites "microechinatus" has an intectate exine and short colpi. Echitriporites "retiechinatus" Fig. A-9, 24 Diagnosis: Echitriporate, mid-sized (30-37um), annulate, annuli 2um wide, tectate, exine 1 .5um thick, spines 2um high, fairly distributed over the entire grain, tectum interechinate is finely reticulate. Specimens: RE 113,7x88.6 Discussion: Echitriporites nuriae Duenas, 1980 is larger (38-47um), with larger spines (up to 6um high), and thinner exine (lum thick), Echitriporites "variabilis" is triangularacute-convex, has spines with rounded ends, and tectum is micropitted. Echitriporites "spissuexinatus" Fig. A-9, 25-26 Diagnosis: Echitriporate, mid-sized (50um), annulate, annuli 0.4um wide, intectate, exine 4um thick, spines 5um high, one grain found Specimens: N18, 18.4x94.2 Discussion: Unique echinate triporate intectate with very thick nexine. Echitriporites triangidiformis var. "orbicularis" Fig. A10, 1-2 Echitriporites trianguliformis forma A Muller et al, 1987, p. 41, pi. 3, fig. 5. Diagnosis: Echitriporate, small to mid-sized (22-32um), circular, pores costate, intectate 0.7um thick, spines 0.8-2. lum long, 0.5um at the base, 0.5um apart, large variation in grain size and spines length. Specimens: PIN 12, 7.3 x 83.5; PIN 12, 8 x 86.5; PIN 35+90, 15 x 83.8

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239 Discussion: This variety is more rounded and with spines more densely distributed than grains of Echitriporites trianguliformis Van Hoeken-Klinkenberg, 1964 from Late Cretaceous strata. Echitriporites "variabilis" Fig. A10, 3-5 Diagnosis: Echitriporate, mid-sized (26-49um), triangular-acute-convex, pores costate, tectate 1.5um thick, larger grains with more and larger spines (3um high), shorter grains with less and shorter spines (1.5um high), tectum micropitted, Specimens: PIN 47+100, 87.8 x 5.7; PIN 28+0, 14.1 x 105.1 Discussion: Echitriporites nuriae Duenas 1980 has larger spines (up to 6um high), and thinner exine (lum thick), Echitriporites "retiechinatus" is elliptic, has spines with pointed ends, and tectum is finely reticulate. Genus Foveodiporites Varma and Rawat, 1963 Foveodiporites guianensis Wijmstra, 1971 Fig. A10, 6-7 Diagnosis: Diporate, rectangular, mid-sized (30-36um), foveolate, foveolae 0.5-0. 8um wide, circular, 7-8um apart, increasing in density near pores. Specimens: N4, 6.5 x 1 10.8 Genus Foveotricolpites Pierce, 1961 Foveotricolpites "costatus" Fig. A10, 8-10

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240 Diagnosis: Tricolpate, mid-sized (33um), costae 4um wide, tectate 2.7um thick, foveolate, two class sizes distributed over entire grain, a large foveolae, 3um wide, and a smaller l-2um wide, one grain found. Specimens: PIN 12, 4 x 100.5 Discussion: Foveotricolpites perforatus Van der Hammen and Garcia, 1966 has foveolae l-2um wide that increase in width toward poles. Foveotricolpites perforatus Van der Hammen and Garcia, 1966 Fig. A10, 11-12 Diagnosis: Tricolpate, prolate, mid-sized(30-50um), tectate 2-3um, foveolate, foveolae l-2um wide, coarser on poles up to 5um, variability in thickness of exine layers. Specimens: N149, 15.9 x 88.2; NA 59+90, 17.8 x 1 10.3 Foveotricolporites "brevicolpatus" Fig. A10, 13-15 Diagnosis: Tricolporate, mid-sized (36um), tectate lum, short colpi, endopore costate and fastigiate, foveolate, lumina decrease from poles to equator, one grain found Specimens: PIN 12, 10 x 87 Discussion: Unique combination of short colpi, fastigiate endopores and foveolae that diminish in width toward equator. Genus Foveotricolporites Pierce, 1961 Foveotricolporites "fossulatus" Fig. A-10, 16-17 Diagnosis: Tricolporate, mid to large-sized (40-6 lum), colpi marginate, pore costate, fossulate/foveolate diminishing toward colpi margines where is micropitted, thick nexine. Specimens: PIN 52+1 10, 7.9 x 89.9

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241 Discussion: Retitricolporites quadrosi Regali et al, 1974 has a costate colpi and indistinct pores, Foveotricolporites crassiexinatus Van Hoeken Klinkenberg, 1966 is smaller (31um), and has an uniform foveolae. Foveotricolporites "marginatus" Fig. A10, 18-19 Diagnosis: Tricolporate, mid-sized (30um), colpi marginate, pore simple, lalongate, fossulate, fossulae diminishing toward colpi margines and poles where is micropitted, nexine thick, one grain found. Specimens: PIN 52+1 10, 17.9 x 82.5 Discussion: Retitricolporites quadrosi Regali et al., 1974 has a costate colpi and indistinct pores, Foveotricolporites crassiexinatus Van Hoeken Klinkenberg, 1966 is smaller (31um), and has an uniform foveolae, Foveotricolporites "fossulatus" is larger (40-6 lum) and poricostate, Foveotricolporites voluminosus Gonzalez, 1967 has a thinner exine (1.8um), poricostate, and foveolate is uniform. Foveotricolporites "microreticulatus" Fig. A10, 20-21 Diagnosis: Tricolporate, mid-sized (30um), prolate, colpi costate, tectate 1.2um thick, fossulate, fossulae l-2um long, 0.4um wide, tectum interfossulate is micropitted, one grain found. Specimens: N 354+120, 14.9x96.5 Discussion: Foveotricolporites "poricostatus" is poricostate, Foveotricolporites "rugulatus" has a thicker tectum (lum), longer fossulae (2-5um long), and tectum interfossulate is psilate.

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242 Foveotricolporites "poricostatus Fig. A10, 22-23 Diagnosis: Tricolporate, mid-sized (36-40um), circular, tectate 2um thick decreasing toward colpi, endopores costate, fossulate, fossulae 2-4um long, evenly distributed over entire grain Specimens: N 174,5.7x99 Discussion: Foveotricolporites "microreticulatus" is colpicostate, Foveotricolporites "rugulatus" has a thicker tectum (lum), and colpi costate. Foveotricolporites "rugulatus" Fig. A10, 24-25 Diagnosis: Tricolporate, mid-sized (28-45um), prolate, fossulate, tectate 1.5-1.8 thick, tectum very thick, ectocolpi costate, fossulae 2-5um long, branching, occasionally fossulae profusely fuses forming a rugulate-like pattern, coarseness of sculpturing and branching pattern of fossulae are variable Specimens: RE 251+30, 18.1 x 88.7; PIN 12, 19.2 x 101 Discussion: Foveotricolporites "poricostatus" is poricostate, Foveotricolporites "microreticulatus" has a thinner tectum, shorter fossulae (l-2um long), and tectum interfossulate is micropitted Genus Foveotriporites Gonzalez, 1967 Foveotriporites hammenii Gonzalez, 1967 Fig. A10, 26 Diagnosis: Triporate, mid to large-sized (42-75um), pore costate, tectate 3um thick, foveolate, lumina 1.5-3.5um wide, foveolate to near reticulate sculpturing Specimens: UR 812, 13 x 96.5 PIN 71+0, 13.2 x 108.5

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243 Foveotriporites "poricostatus Fig. A-ll, 1-4 Diagnosis: Triporate, mid-sized (50um), costae thick, tectate lu thick, foveolate, lumina 0.5um wide. Specimens: PIN 81+0, 16.3 x 105.5; PIN 81+0, 19.1 X 89.7 Discussion: Foveotriporites hammeni Gonzalez 1967 has a thicker exine (3um) and larger foveolae (1.5-3.5 um). Genus Gemmamonocolpites Van der Hammen and Garcia, 1965 Gemmamonocolpites "ambigemmatus" Fig. A-ll, 5-6 Diagnosis: Gemmamonosulcate, mid-sized (35-40um), intectate 0.5um thick, two types of sculpturing, a large gemmae sparsely distributed, mushroom-like, 2um high, and a small clavae, densely distributed, lum high, density of large gemmae is variable. Specimens: UR 812, 21 x 84.4 Discussion: Gemmamonocolpites "perfectus" is more densely gemmate and exine intergemmae is scabrate, Gemmamonocolpites "megagemmatus" has larger gemmae (45um high), Racemonocolpites Gonzalez 1967 has gemmae densely distributed. Gemmamonocolpites gemmatus (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Fig. A-ll, 7-8 Diagnosis: Gemmamonosulcate, samll to mid-sized (24-33um), intectate 0.5um thick, gemmae 0.3-1.5um high, fairly to moderately distributed, variable in density of larger gemmae, from sparsely to moderately distributed, but always shorter than 1.5 um Specimens: N 4, 7.8 x 100.5 N 45, 20 x 87.1

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244 Gemmamonocolpites "mammiformis" Fig. A11, 9-10 Diagnosis: Gemmamonosulcate, mid-sized (32um), intectate 0.8um thick, gemmae 2um high, sparsely distributed, exine at the base of the gemmae rises giving the appearance of a mammary gland, one grain found Specimens: N 18, 11.5 x 94 Discussion: Gemmamonocolpites "perfectus" has spherical gemmae and exine thickness is constant, Gemmamonocolpites "megagemmatus" has larger gemmae (4-5um high). Gemmamonocolpites macrogemmatus Muller et ah, 1987 has large gemmae (up to 3um high), and exine thickness . Gemmamonocolpites "megagemmatus" Fig. A-ll, 11-13 Diagnosis: Gemmamonosulcate, mid-sized (42um). intectate 0.5um thick increasing to 2um below gemmae, gemmae in two size-classes, a gemmae 4-5um high, and other group 1-1. 5um high. Specimens: PIN 52+1 10, 18.8 x 87.1; PIN 52+1 10, 5.2 x 1 1 1.4 Discussion: Gemmamonocolpites "mamiformis" has shorter gemmae (2um high), Gemmamonocolpites "ambigemmatus" has a shorter gemmae (2um high), and thickness of exine is constant, Gemmamonocolpites macrogemmatus Muller etai, 1987 has shorter gemmae (up to 3um high). Gemmamonocolpites "perfectus" Fig. A-ll, 14-15 Diagnosis: Gemmamonosulcate, mid-sized (40um), intectate 0.5um thick , gemmae 12um high, sparsely distributed up to 40 gemmae/grain, intergemmae exine scabrate, scabrae densely distributed, variable in size and density of gemmae.

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245 Specimens: PIN 52+1 10, 1 1 x 86 Discussion: Gemmamonocolpites "ambigemmatus" is less densely gemmate and has small clavae densely distributed, Gemmamonocolpites gemmatus (Van de Hammen, 1954) Van der Hammen and Garcia, 1966 is smaller (24-28um), gemmae is smaller (0.31 .5um), and lack a densely distributed scabrae, Gemmamonocolpites "mammiformis" has a mamiform-like gemmae and exine thickens below the sculpturing elements, Gemmamonocolpites macrogemmatus Muller et al, 1987 has larger gemmae (up to 3um high), and exine is thicker (lum), Racemonocolpites Gonzalez 1967 has gemmae densely distributed. Genus Jandufouria Germeraad et al, 1968 Jandufouria "minor" Fig. A-ll, 16-18 Diagnosis: Stephanocolporate, midsized (26-36um) with a even and dense fine reticulum, circular lumina 0.5um wide, 4-6 colpores. Specimens: PIN 63+20, 4.3 x 84 Discussion: Very similar to Jandufouria seamrogiformis Germeraad et al, 1968 but J. seamrogiformis is consistently larger (range of 40-57um) and with a larger colpi, reaching half-way the poles, Retistephanocolpites angeli Leidelmeyer, 1966 is larger (3550), colpate, with a thicker tectum (2.2um) and has a larger lumina that tends to be elongated and angular, Retistephanocolpites tropicalis Duenas, 1980 is 4-colpate and colpi is not costate, Retistephanocolporites quadriporus Van der Hammen and Wymstra, 1964 has 4 pores and 4 colpi. Genus Jussitriporites Gonzalez 1967 Jussitriporites "psilatus" Fig. A-ll, 19-21

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246 Diagnosis: Triporate, mid-sized (28-40um), atectate 0.6um thick, psilate, costae well developed, protruding, costa width is variable (2-4um), sometimes in tetrads. Specimens: N 4, 16.5 x 100 N 27, 13.3 x 91.6 N 1 10, 6.2 x 82.3 Discussion: Jussitriporites undulatus Gonzalez 1967 has a thicker tectate exine (3.2um), larger size (54-6 lum), and a psilate-verrucate sculpture. Jussitriporites undulatus Gonzalez, 1967 Fig. A-11,22 Diagnosis: Triporate, mid-sized (36-50um), exine 2-3. 2um thick, costae very well developed and protruding, with an undulating rugulate sculpture, density of rugulae is variable from almost psilate to highly rugulate. Specimens: PIN52+1 10, 3.8 x 101.8; PIN75+160, 17.3 x 87.9; RE 132, 20.5 x 113 Genus Ladakhipollenites Mathur and Jain, 1980 Ladakhipollenites "gemmatus" Fig. A11, 23-24 Diagnosis: Psilatricolpate, mid-sized (28um), colpi simple, colpi membrane ornamented with gemmae, one grain found. Specimens: RE 67+120, 6.3 x 1 12.8 Ladakhipollenites rubini (Van der Hammen, 1954) comb, nov Fig. A-l 1,25-26 Tricolpites rubini Van der Hammen, 1954, p. 93, pi. 8. Diagnosis: Psilatricolpate-colporate, small-sized (1 l-14um), colpi long, costae well defined, tectate, pores absent or present. Specimens: PIN 42+100, 4.6 x 103.2

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247 Discussion: Tricolpites Van der Hammen, 1954 is illegitimate and a junior synonym of Bartsia (Jansonius and Hills, 1976, card 2971). Ladakhipollenites simplex (Gonzalez, 1967) Jaramillo comb. nov. Fig. A-11,29 Psilatricolpites simplex Gonzalez, 1967, p. 27, pi. 1, figs. 3-3a. Diagnosis: Psilatricolpate, mid-sized (28-32um),prolate, colpi long, slightly marginate, nexine thick, and columellae indistinct. Specimens: RE 190+10, 3.5 x 103.1 Discussion: Psilatricolpites (Van der Hammen 1954b) Pierce 1961 is an obligate junior synonym of Tricolpites Van der Hammen 1954, because they have same type species, as the latter is illegitimate and a junior synonym of Bartsia, so is Psilatricolpites (vide Psilatricolpites (Jansonius and Hills, 1976, card 2233). Genus Longapertites Van Hoeken Klinkenberg, 1964 Longapertites microfoveolatus Adegoke and Jan du Chene, 1975 Fig. A-l 1,27-28 Diagnosis: Longaperturate, mid-sized (42-53um), with micropitted sculpturing and a very thin tectate wall, 0.8um thick. Specimens: N 87, 18 x 81 Longapertites "ornatus" Fig. A12, 1-3 Diagnosis: Longaperturate, mid-sized (40-45um), semitectate 1.7um thick, large reticulate, lumina (4-6um wide) decreasing near colpus, simplicolumellate, it could be a gradation to L. proxapertitoid.es reticuloides, however the lumina is much wider in L. "ornatus".

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248 Specimens: PIN 52+1 10, 2.9 x 99.9 Discussion: Longapertites proxapertitoid.es var. reticuloides Van der Hammen and Garcia, 1966 has a narrower reticulate lumina (l-3um) and thicker muri (l-1.5um), Longapertites marginatus Van Hoeken Klinkenberg, 1964 has a coarser reticulate pattern on the proximal side. Longapertites proxapertitoides var. proxapertitoides Van der Hammen and Garcia, 1966 Fig. A12, 4 Diagnosis: Longaperturate, mid to large-sized (34-70um), tectate 1.5um thick, foveolate, lumina 0.5-2um, lumina diameter varies from 0.5um to 2um, seems to be a gradual transition to L. proxapertitoides var. reticuloides. Specimens: N 265, 13.4 x 93.5; N 265, 5.5 x 1 10.2; RE67+120.10.4 x 104.7 Longapertites proxapertitoides var. reticuloides Van der Hammen and Garcia, 1966 Fig. A12, 5 Diagnosis: Longaperturate, mid to large-sized (35-50um), tectate 1.5-3um thick, reticulate, lumina l-3um, lumina diameter varies from lum to 3um, seems to be a gradual transition to L. proxapertitoides var. proxapertitoides. Specimens: N 265, 8 x 84.3 N 265, 5.6 x 108.2 Genus Luminidites Pocknall and Mildenhall, 1984 Luminidites "colombianensis" Fig. A12, 6-8 Diagnosis: Trichotomosulcate, large-sized (35-46um), exine semitectate, lum thick, reticulate, lumina lum at poles diminishing gradually toward radial equatorial areas. Specimens: PIN 28+0, 11.9 x 106.8

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249 Discussion: Syndemicolpites Van Hoeken-Klinkenberg, 1964 is diplotrichotomosulcate, Luminidites reticulatus (Couper) Pocknall and Mildenhall, 1984 has a thicker exine (12um), wider lumina (4.5-9um) that decrease toward distal pole, pluricolumellate (Jansonius and Hills, 1985). Genus Margocolporites Ramanujam 1966 ex Srivastava 1969, emend. Pocknall and Mildenhall 1984 Margocolporites vanwijhei Germeraad et al. , 1968 Fig. A12, 9 Diagnosis: Retitricolporate, mid-sized (40-42um), costate, with wide margines, coarseness of sculpture is variable. Specimens: RE 67+120, 6.9 x 107 Genus Mauritiidites Van Hoeken-Klinkenberg, 1964 Mauritiidites franciscoi var. franciscoi (Van der Hammen, 1956) Van Hoeken Klinkenberg, 1964 Fig. A-12, 10-15 Diagnosis: Echinate monosulcate, mid-sized (30-56um), with rooted spines, intectate 0.8-1.7 um, shape and size of spines are variable. The greatest variability seems to be in the middle Eocene (PIN 12-PIN 50). Specimens: N21+100, 12 x 107.5; PIN 12, 3.3 x 104; PIN 12, 6.8 x97.9; PIN 28+0, 11.1x89; PIN 39+166, 8 x 79; PIN39+ 166, 17,9 x 85.2 Mauritiidites franciscoi var. minutus Van der Hammen and Garcia, 1966 Fig. A-12, 16 Diagnosis: Echinate monosulcate, mid-sized (25-33um), with rooted spines, intectate <0.9 um, size of spines 0.5-1.8um.

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250 Specimens: N 354+120, 7.6 x 80.5 Discussion: Mauritiidites franciscoi var franciscoi Van der Hammen and Garcia, 1966 has larger spines (1.5-5um), a thicker exine (>0.8um), and in general a larger size. The grain seems to grade into M. franciscoi franciscoi but its retained as a separated species because its size-range approaches a normal distribution. Mauritiidites franciscoi var. pachyexinatus Van der Hammen and Garcia, 1966 Fig. A12, 17 Diagnosis: Echinate monosulcate, mid to large-sized (40-60um), with rooted spines, intectate >2 um, wall thickness 2-3um, spines size (2.5-5um high), shape conical, to subcorneal Specimens: PIN39+166, 20.4 x 19.4 PIN 19+60, 8.4 x 87.3 Genus Momipites Wodehouse, 1933, emend. Nichols, 1973 Momipites africanus Van Hoeken Klinkenberg, 1966 Fig. A12, 18-19 Diagnosis: Psilatriporate, mid-sized (26-30um), atectate lum thick, triangular-obtuseconvex, pores slightly protruding, and atria slightly developed. Specimens: N 21+100, 7.1 x87.1;N 18,8.9x87.1 Momipites "pachyexinatus" Fig. A12, 20-21 Diagnosis: Psilatriporate, mid-sized (38-46um), triangular-obtuse-convex, pores simple, border irregular, exine tectate thick (1.5um), columellae indistinct, atrium slightly developed, pore borders are highly irregular. Specimens: PIN 32+0, 16.1 x 97.6

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251 Discussion: Momipites africanus Van Hoeken Klinkenberg, 1966 is smaller (<25um), polar shape is more triangular, and exine is atectate and thinner (<1.2um), Cricotriporites Leidelmeyer, 1966 has a circular or elliptic shape, and pores are annulate or costate Genus Monoporopollenites Meyer, 1956 Monoporopollenites annulatus (Van der Hammen, 1954) Jaramillo comb. nov. Fig. A12, 22-23 Monoporopollenites annulatus Van der Hammen, 1954, p. 90, pi. 6 Diagnosis: Monoporate, mid-sized (25-40um), psilate, tectate thin (0.6um thick), and a costate pore slightly protruding, aperture (2-4um), costae width (2-3 urn). Specimens: PIN 35+90, 18.2 x 82.4 N 354+120, 10.5 X 83.7 Discussion: Monoporites is a nodem nudum (Jansonius and Hills, 1976, card 1705). Monoporopollenites Meyer, 1956 includes monoporate, psilate grains (Jansonius and Hills, 1976). Genus Nothofagidites Potonie 1960 Nothofagidites "huertasi" Fig. A12, 24-25 Diagnosis: Scabrastephanoporate, mid-sized (26-45um), pore circular, annulate, tectate exine very thin (0.6um), scabrae <0.7um high, fairly distributed, in larger grains several elements of the sculpture seem spines however always shorter than 0.7um. Specimens: PIN 66+80, 10 x 95 PIN 66+80, 18.7 x 96.2 Discussion: Echistephanoporites alfonsi Leidelmeyer, 1966 is smaller (18-19um), and has clearly defined spines lum high, Nothofagidites "lolongatus" has a lolongate pore and a wider annuli (2um), Nothofagidites flemingii (Couper 1953) Potonie 1960 has more pores (7-9), exine is thicker (lum), and annuli is thicker (2-3um) (Jansonius and Hills, 1976); Polyatriopollenites Pflug 1953 is atriate (Jansonius and Hills, 1976).

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252 Nothofagidites "lolongatus" Fig. A12, 26-27 Diagnosis: Scabrastephanoporate, mid-sized (24-38um), pore lolongate, annulate, tectate very thin (0.8um), scabrae <0.5um high, fairly distributed. Specimens: RE 241+40, 18 x 92.7 Discussion: Echistephanoporites alfonsi Leidelmeyer, 1966 is smaller (18-19um), and has clearly defined spines lum high, Nothofagidites "huertasi" has a circular pore and a more narrow annuli (l-1.5um), Verrustephanoporites "gemmatus" has a larger sculpture (>0.7um), Polyatriopollenites Pflug 1953 is atriate, Nothofagidites flemingii (Couper 1953) Potonie 1960 is larger (37-54um), has more pores (7-9), is convex between pores in polar view, and more spaced granules (2-3um apart). Genus Perfotricolpites Gonzalez, 1967 Perfotricolpites digitatus Gonzalez, 1967 Fig. A12, 28 Diagnosis: Tricolpate, mid-sized (38um), finely reticulate, with digitate columellae. Specimens: PIN 42+100, 9.2 x 96.5 Genus Periretisyncolpites Keiser and Jan du Chene, 1979 Periretisyncolpites giganteus Keiser and Jan du Chene, 1979 Fig. A13, 1 Diagnosis: Syncolpate, large-sized (1 lOum), ectocolpi marginate, tectate 8um thick, reticulate, lumina of variable shapes and sizes, 4um long, muri 3-4um wide, one grain found Specimens: LaPaz712m, 10x81.2

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253 Periretisyncolpites "inciertus" Fig. A13, 2-5 Diagnosis: Periretisyncolpate, large-sized (1 10-120um), with a reticula formed by a large lumina surrounded by several smaller lumina, only two intercolpia found. Specimens: N 18, 7 x 97.6 Discussion: Periretisyncolpites giganteus Keiser and Jan du Chene, 1979 has a more even lumina, a larger number of columellae, and a small overall size, Periretisyncolpites magnosagenatus (Van Hoeken Klinkenberg) Keiser and Jan du Chene, 1979 has an uniform lumina size (Keiser and Jan du Chene, 1979). Genus Perisyncolporites Germeraad et al., 1968 Perisyncolporites pokornyi Germeraad et al. , 1 968 Fig. A13, 6 Diagnosis: Syncolporate psilate, mid-sized (23-25um), tectate 3um thick, with colpi arranged in a complex pattern and pores < colpi, number and arrangement of colpi and pores is variable, sometimes sexine is lost and grain appears periporate. Specimens: RE 241+40, 6 x 94.5; PIN 52+1 10, 5.7 x 84.5 Genus Propylipollis Martin and Harris, 1975 Propylipollis "pseudocostatus" Fig. A13, 7-9 Diagnosis: Psilatriporate, triangular-acute-straight, mid-sized (27um), with evenly distributed, very fine reticulation and segmented costae, one grain found Specimens: PIN 12, 12.6 x 113 Discussion: Proteacidites dehaani Germeraad et al, 1968 has a larger reticulum, coarser in interporate fields, and a continuous costa, Proteacidites miniporatus Van Hoeken Klinkenberg 1966 is scabrate, Propylipollis amolosexinus (Dettmann and Playford,

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254 1968) Dettmann and Jarzen, 1996 is larger (35-56um), and thinner exine (2-3um thick) (Dettmann and Jarzen, 1996). Genus Proxapertites Van der Hammen 1956, emend. Singh, 1975 Proxapertites cursus Van Hoeken Klinkenberg, 1966 Fig. A-13, 10 Diagnosis: Proxaperturate, mid to large-sized, with coarse and even reticulation" "Size 29-60um, thickness of exine Specimens: NA 59+90, 12.8 x 108.5 Proxapertites humbertoides (Van der Hammen, 1954) Sarmiento, 1992 Fig. A-13, 11-12 Diagnosis: Proxaperturate, large-sized (73-1 2 lum), foveolate, foveolae lumina 2-6um, shape and degree of fusion of columellae is variable, lumina varies from circular to elongated to stellate or in a zig-zag pattern. Specimens: N 74, 14.7 x 90; N 354+120, 8.2 x 89; PIN 12, 6.2 x 100.2; UR 531+120, 21 x81.5 Proxapertites magnus Muller et al, 1987 Fig. A-13, 13-14 Diagnosis: Proxaperturate, large-sized (60-95um) with foveolate lumina <1.5um, shape and density of columellae is variable, lumina diameter 0.8-1.5um. Specimens: N 87, 6.2 x 84.5; N 27, 20.2 x 98.1; RE 67+120, 23 x 100 Proxapertites operculatus (Van der Hammen, 1956) Germeraad et al., 1968 Fig. A-13, 15 Diagnosis: Proxaperturate, mid-sized, with fine even reticulation.

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255 Specimens: NA 59+90, 4.9 x 84. 1 Discussion: Proxapertites cursus Van Hoeken Klinkenberg, 1966 has a wider and less even lumina, and exine is thicker. Proxapertites psilatus Sarmiento, 1992 Fig. A-13, 16-17 Diagnosis: Proxaperturate, mid-sized (25-37um), with psilate, scabrate to micropitted sculpturing and a thin tectate exine, 0.8um-1.2um thick, sculpturing being scabrate to psilate to micropitted. Specimens: N 354+120, 19.1 x 91.5; PIN 42+100, 5.5 x 100.5 Proxapertites verrucatus Sarmiento, 1992 Fig. A-13, 18-19 Diagnosis: Proxaperturate, mid-sized (27-35um), verrucate, density and high of verrucae is variable. Specimens: UR531+120,14.8xl02.9; UR 507, 10.5 x 97.1 Genus Psilabrevitricolpites Van Hoeken Klinkenberg, 1966 Psilabrevitricolpites "costatus" Fig. A-13, 20-21 Diagnosis: Psilatricolpate, mid-sized (30um), colpi very short, costate, atectate 0.8um thick, psilate, one grain found. Specimens: N18, 9.8 x 104 Discussion: Lakiapollis Venkatachala and Kar, 1969 is brevitricolporate (Jansonius and Hills, 1976).

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256 Genus Psilabrevitricolporites Van der Kaars, 1983 Psilabrevitricolporites "costatus" Fig. A13, 22-23 Diagnosis: Psilatricolporate, mid-sized (40um), colpi very short, tectate, conspicuously poricostate, micropitted, one grain found. Specimens: PIN 42+100,12.3x1 12.5 Discussion: Psilabrevitricolporites "operculatus" is smaller and operculate, Lakiapollis Venkatachala and Kar 1963 is psilate-scabrate (Jansonius and Hills, 1976). Psilabrevitricolporites "operculatus" Fig. A13, 24-25 Diagnosis: Psilatricolporate, small-sized(19um), colpi very short, pore costate, psilate, one grain found. Specimens: PIN 39+166, 16 x 100.5 Discussion: Psilatricolporites operculatus Van der Hammen and Wymstra, 1964 has a longer and marginate colpi, and operculum is wider (1.5 um). Psilabrevitricolporites simpliformis Van der Kaars, 1983 Fig. A14, 1-2 Diagnosis: Psilatricolporate, mid-sized (26-32um), triangular-acute-convex, colpi very short, pore costate, atectate 0.8um thick, psilate to finely scabrate, varies in the costae width, in the size of polar darkening, and sculpture type (psilate to finely scabrate). Specimens: N 21+100, 12 x 107.1; N 21+100, 10 x 106.1; N 27, 12.5 x 100.5 Genus Psilamonocolpites Van der Hammen and Garcia, 1966 Psilamonocolpites grandis (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Fig. A-14, 3-4

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257 Diagnosis: Psilamonosulcate, 30-60um long, atectate, exine lum thick, sculpture psilate to micropitted Specimens: N 4, 5.5x88.2 Discussion: Van der Hammen and Garcia, 1966 separates P. grandis from other three species of Psilamonocolpites on the basis of size. However, an overlap in sizes was found between P. medius and P. grandis. P. grandis is retained here because its distinctive thick exine (lum), thicker than P. medius (<0.5um). Psilamonocolpites medius (Van der Hammen, 1954) Van der Hammen and Garcia, 1966 Fig. A-14, 5-6 Diagnosis: Psilamonosulcate, mid-sized (29-50um), atectate, exine <0.5 um thick, sculpture psilate to micropitted. Specimens: N 74, 14 x 112.1 Discussion: Van der Hammen and Garcia, 1966 separates P. medius from other three species of Psilamonocolpites on the basis of size. Here it was found that there is an overlap in size between P. medius and P. grandis. However, P. medius is retained here because its distinctive thin exine (<0.5um). Genus Psilaperiporites Puri 1963 Psilaperiporites "enigmaticus" Fig. A-14, 7-8 Diagnosis: Psilaperiporate, small-sized (22um), circular, pores 9, 3 in equator, the other 6 opposite to each other half-way equator-pole, slightly annulate, atectate (lum), one grain found. Specimens: NA -2, 16.8 x 91.5 Discussion: Psilaperiporites "pachyexinatus" has 12 pores, and it is tectate, Anacolosidites luteoides Cookson and Pike 1954 has six pores, it is tectate, and

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258 subtriangular in polar view (Jansonius and Hills, 1985), Cretacaeiporites mulleri Herngreen, 1973 is tectate and has a scabrate pore membrane. Psilaperiporites "pachyexinatus" Fig. A14, 9-10 Diagnosis: Periporate, small-sized (26um), psilate, pores 12, annulate, thick nexine and very thin sexine, one grain found. Specimens: PIN 71, 15 x 107 Discussion: Psilaperiporites "pauciporatus" has 18-23 pores, and a micropitted sculpture. Psilaperiporites "pauciporatus" Fig. A-14, 12-13 Diagnosis: Periporate, small to mid-sized (20-32um), micropitted, pores 18-23, slightly annulate. Specimens: PIN 12, 13.5 x 87.2 Discussion: Psilaperiporites robustus Regali et ai, 1974 has 60-64 pores, larger in diameter (4um), and a larger body size (45-48 um), Scabraperiporites nativensis Regali etal, 1974 is scabrate. Genus Psilastephanocolpites Leidelmeyer, 1966 Psilastephanocolpites "marginatus" Fig. A-14, 14-16 Diagnosis: Psilastephanocolporate, mid-sized (53um), atectate lum thick, and colpi marginate, one grain found Specimens: PIN 81+0, 15 x 105

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259 Discussion: Psilastephanocolpites maia Leidelmeyer, 1966 is tectate, has a thicker exine (1.8um), and is smaller (27um). Psilastephanocolpites "punctum" Fig. A14, 17-18 Diagnosis: Stephanocolpate, densely micropitted, small-sized (26um), tectate 0.9um thick, and with very short costate colpi, one grain found Specimens: PIN 42+100, 15.5 x 1 10 Discussion: Psilastephanocolpites maia Leidelmeyer, 1966 has a thicker exine (1.8um), and colpi is longer. Genus Psilastephanocolporites Leidelmeyer 1966 Psilastephanocolporites "brevicolpatus" Fig. A14, 19-21 Diagnosis: Psilastephanocolporate, mid-sized (26-28um), tectate 0.7um thick, with very short 10-14 meridional ectocolpi, and a zonocolpus costate, columellae distinctiveness is variable. Specimens: PIN 42+100, 6.9 x 109.5; PIN 52+1 10, 8 x 90.9 Discussion: Psilastephanocolporites fissilis Leidelmeyer, 1966 has meridional colpi almost reaching the polar areas, and a thicker exine (2 um), Psilastephanocolpites globulus Van der Kaars, 1983 has only 4 colpi, costa is thicker (2um), and exine is atectate, Psilastephanocolporites globulus Van Hoeken-Klinkenberg, 1966 does not have an equatorial colpus. Psilastephanocolporites fissilis Leidelmeyer, 1966 Fig. A14, 22-24

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260 Diagnosis: Psilastephanocolporate, mid-sized (22-32um)„ prolate, atectate 1.5-2.5um thick, with a meridional ectocolpi very long and a zonocolpus costate, costae thickness (0.5-2 urn). Specimens: PIN 28+0, 1 1.6 x 108.2; PIN 19+60, 9.4 x 98.5; PIN 52+1 10, 12.4 x 109.5 Discussion: Psilastephanocolporites "brevicolpatus" has a shorter meridional colpi, and a thinner exine (< 1 um). Psilastephanocolporites "pachyexinatus Fig. A14, 25-28 Diagnosis: Psilastephanocolporate, large (45-53um), tectate (4-5um), nexine very thick, colpi large-sized, marginate by thinning of nexine, exine thickness (4-5um); 3-4colporate. Specimens: PIN 55+30, 13.5 x 85.1; PIN 28+0, 1 1.9 x 98; PIN 28+0, 8.1 X 97.6 Discussion: Psilastephanocolporites "psilatus" has a shorter colpi, and thinner exine (<2um). Psilastephanocolporites "psilatus" Fig. A15, 1-2 Diagnosis: Psilastephanocolporate, large-sized (30-52um), tectate (1.5-2um), nexine very thick, colpi short to mid-sized, marginate by thinning of nexine, poricostate; 4-6colporate, in few grains the colpi is larger, reaching half-way between the equator and the pole, costa thickness (0.5-2um) Specimens: PIN 81 +0, 14 x 91.5; PIN 81+0, 17.8 x 1 10.8 Discussion: Psilastephanocolporites "pachyexinatus" has a larger colpi, and thicker exine (4-5um).

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261 Genus Psilastephanoporites Regali, et al. ,1974 ex Hoorn, 1993 Psilastephanoporites "annulatus" Fig. A15, 3-4 Diagnosis: Psilastephanoporate, large-sized (42um), 4-porate, annulate, and atectate 1.2um thick., one grain found. Specimens: UR 761, 16.2 x 86.9 Discussion: Psilastephanoporites caribiensis Duenas, 1980 is smaller (26-3 lum), and tectate, Psilastephanoporites stellatus Regali et al. ,1974 has 6 pores in two groups of three, Psilastephanoporites "scabratus" has a thinner exine (0.5), annuli is more narrow (2um). Psilastephanoporites "distinctus" Fig. A15, 5-6 Diagnosis: Psilastephanoporate, mid-sized (26-40um), rhombic, pores annulate, protruding and above equator. Specimens: PIN 52+1 10, 1 1.2 x 85.6 Discussion: Venezuelites globoannulatus Muller et al., 1987 has a thicker annulus (9um), and a thicker exine (2.5um). Psilastephanoporites "scabratus" Fig. A-15,7-8 Diagnosis: Stephanoporate, mid-sized (3 lum), scabrate in poles, psilate in equator, 4porate, pore intruding, annulate, atectate (0.5um), one grain found. Specimens: N 149, 10.5 x 101.2 Discussion: Psilastephanoporites caribiensis Duenas ,1980 is tectate, and exine is thicker (1.5um), Psilastephanoporites stellatus Regali et al., 1974 has 6 pores in two

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262 groups of three, Psilastephanoporites "annulatus" has a thicker exine (1.2), annuli is wider (5um), Genus Psilasyncolporites Leidelmeyer ex Gonzalez, 1967 Psilasyncolporites "fastigiatus" Fig. A15, 9-10 Diagnosis: Psilasyncolporate, mid-sized (29um), colpi simple, pores costate, fastigiate, apocolpial field lOum wide, tectate 2um thick, columellae indistinct, sexine thick (1.2um), one grain found. Specimens: RE 132, 19.5 x 1 1 1.1 Discussion: Syncolporites poricostatus Van Hoeken Klinkenberg, 1966 has a thinner exine (1.2um) and it is smaller (14.5 um). Psilasyncolporites "psilatus" Fig. A15, 11-12 Diagnosis: Psilasyncolporate, small-sized (13um), colpi costate, poricostate, apocolpial field absent, tectate lum thick, columellae distinct., one grain found. Specimens: PIN 47+100, 12.8 x 89.5 Discussion: Syncolporites poricostatus Van Hoeken Klinkenberg, 1966 has a pore fastigiate, and a colpi simple, Syncolporites incomptus Van Hoeken Klinkenberg, 1964 is larger (20-23um), and apertures are simple, Psilasyncolporites parcus Gonzalez, 1967 has a thinner exine (
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263 Diagnosis: Psilatricolporate, mid-sized (30um), with a thick exine (2um) and a distinct and long columellas costae 1 .2um thick foming a belt at the equator and decreasing gradually toward poles, one grain found Specimens: PIN 52+1 10, 5.5 x 1 12 Discussion: Psilatricolporites obscurus Gonzalez, 1967 has a thicker exine (4.8um), and an equatorial colpus, Psilatricolporites optimus Gonzalez, 1967 has a perforate tectum and a costa is absent. Psilatricolporites crassus Van der Hammen and Wymstra, 1964 Fig. A-15, 16 Diagnosis: Psilatricolporate, mid-sized-sized (33-55um)„ colpi medium-sized, pore lalongate costate, tectum thick with columella clearly distinct, sculpturing and thickness of the wall extremely variable, a few grains are tricolpates. Specimens: PIN 12, 12.3 x 84.5; PIN 12, 14.9 x 1 10 Psilatricolporites maculosus Regaliera/., 1974 Fig. A-15, 17-18 Diagnosis: Psilatricolporate, prolate, small to mid-sized (24-36um), colpi short to medium-sized, equatorial costa conspicuous, and pores lalongate. Specimens: PIN 75+160, 20 x 87 Psilatricolporites operculatus Van der Hammen and Wymstra, 1964 Fig. A-15, 19 Diagnosis: Tricolporate, small-sized (18-21um), psilate-micropitted, operculate. Specimens: PIN 39+166, 9.8 x 84.6

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264 Psilatricolporites "orbicularis" Fig. A15, 20-22 Diagnosis: Psilatricolporate, mid-sized (25-33 um), tectate, colpi long, slightly marginate, pores circular, costate. Specimens: RE 143+120, 20 x 93.7 Discussion: Psilatricolporites "poricostatus" is atectate, has a colpi shorter, and colpi is simple. Psilatricolporites "poricostatus" Fig. A15, 23-24 Diagnosis: Psilatricolporate, triangular-obtuse-convex, small-sized (25um), colpi midsize, pores costate, atectate thin (0.5 um), one grain found Specimens: PIN 42+100, 9.7 x 87.8 Discussion: Psilatricolporites marginatus Van der Kaars 1983 has a exine thicker, tectate, and a colpi costate, Psilatricolporites "orbicularis" is tectate, has a colpi longer, and colpi is slightly marginate. Psilatricolporites "singularis" Fig. A-15, 25-28 Diagnosis: Psilatricolporate, mid-sized (31 um), colpi marginate, pores with two rings, outer by thinning of nexine, inner by thickening of nexine, sexine absent near colpi, one grain found. Specimens: PIN 42+100, 20.6 x 100.2 Discussion: Unusual double ring around pores has not been reported in any species. Psilatricolporites "spongiosus" Fig. A-15, 29-30

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265 Diagnosis: Psilatricolporate, subprolate, mid-sized(30-41um), colpi long, equatorial costa very thick, and tectum spongy, continuous equatorial costa in not always well defined, sometimes the endexine thickening is only around pores without being interconnected with each other. Specimens: N 149, 6.2 x 93 Discussion: Psilatricolporites maculosus Regali et al, 1974 is very similar but exine is thinner (1.2um) and not spongy , colpi shorter (up to half-way pole-equator), and costa is thinner (lum), Psilatricolporites transversalis Duenas, 1980 is smaller (20-22um), colpi is short and indistinct, and tectum is non spongy. Psilatricolporites transversalis Duenas, 1980 Fig. A15, 31 Diagnosis: Psilatricolporate, subprolate, mid-sized (26-40um) with a highly protruding costa surrounding lalongate pores, very short indistinct colpi, and a equatorial band of endexine thickening, colpi length 0.5-8um, equatorial colpi sometimes absent to very tenuous. Specimens: PIN 52+1 10, 9.7 x 1 10.4 N 131, 19.2 x 1 1 1.3 Discussion: Psilatricolporites maculosus Regali et al, 1974 does not have a highly protruding costa, and colpi is distinct. Psilatricolporites triangularis Van der Hammen and Wymstra, 1964 Fig. A-15,32 Diagnosis: Psilatricolporate, small-sized (20-25um), triangular-obtuse-convex in polar view, and pores conspicuously costate. Specimens: PIN 81+0, 10.9X87.6

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266 Genus Psilatriporites (Van der Hammen, 1956) Mathur, 1966 ex Hoorn, 1993 Psilatriporites "tenuiexinatus" Fig. A-15, 33-34 Diagnosis: Psilatriporate, triangular-acute-convex, mid-sized (30-3 lum), atectate, exine very thin (0.5um), annulate, annuli narrow and thin. Specimens: UR 531+120, 12.3 x 106.2 Discussion: Proteacidites dehaani Germeraad et ai, 1968 is reticulate, Proteacidites miniporatus Van Hoeken Klinkenberg, 1966 is scabrate and exine thicker, Propylipollis "pseudocostatus" is reticulate. Genus Racemonocolpites Gonzalez, 1967 Racemonocolpites "costagemmatus" Fig. A16, 1-2 Diagnosis: Gemmamonosulcate, mid-sized (43-50um), sulcus costate, intectate 0.5um thick, gemmae l-1.5um high, densely distributed over the entire grain. Specimens: N 354+120, 9.9 x 93.5 PIN 71+0, 9.3 x 106 Discussion: Racemonocolpites racematus (Van der Hammen, 1954) Gonzalez, 1967 is shorter (36um), has larger gemmae (1.5-2um high), and a longer sulcus. Racemonocolpites facilis Gonzalez, 1967 Fig. A-15, 35 Diagnosis: Gemmamonosulcate, mid-sized (35-50um), sulcus simple, intectate 0.5um thick, gemmae variable in shape and size within same grain, 3-4um high, densely distributed over the entire grain, slightly scabrate in intergemmate areas specimens: UR 812, 13.9 x 104.4; La Paz 712m,13.5 x 83.5; PIN 66+80, 13.2 x 105.9

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267 Racemonocolpites racematus (Van der Hammen, 1954) Gonzalez, 1967 Fig. A16, 3-4 Diagnosis: Gemmamonosulcate, mid-sized (36-56um), colpi simple, intectate 0.5um thick, gemmae 1 .5-2um high, densely distributed over entire grain. Specimens: N 27, 8.2 x 85.7; RE 67+120, 16.2 x 99.4; UR 761, 14.7 x 1 1 1 Genus Retibrevitricolpites Van Hoeken Klinkenberg, 1966 Retibrevitricolpites "costatus" Fig. A16, 5-6 Diagnosis: Retibrevitricolpate, mid-sized (29-33 um), micropitted, lumina 0.5um wide, uniform, colpi costate. Specimens: PIN 81+0, 17.9 x 80.8 Discussion: Retibrevitricolporites "speciosus" does not have an uniform lumina, Retibrevitricolporites "grandis" has a pore costate, and reticulate lumina wider (0.5-0.9), Retibrevitricolpites "santanderensis" has a thinner exine (lum), lumina is wider (0.70.9um) and costae is wider (3um). Retibrevitricolpites retibolus Leidelmeyer,1966 Fig. A15, 36-37 Retibrevitricolpites retibolus Leidelmeyer, 1966, p. 53, pi. 2, fig. 4. Retibrevitricolpites increatus Gonzalez, 1967, p. 35, pi. 12, figs. 9-9a. Retibrevitricolpites catatumbus Gonzalez, 1967, p. 36, pi. 12, figs. 8-8b. Diagnosis: Retibrevitricolp(or)ate, small (13-20um), pore costate, reticulum uniform, lumina 0.5um in diameter, tectate, colpate/colporate. Specimens: PIN 39+166, 8.5 x 111.7; PIN 39+166, 16 x 96

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268 Retibrevitricolpites "santanderensis" Fig. A-15, 38-39 Diagnosis: Retibrevitricolpate, small to mid-sized(22-30um), tectate lum thick slightly decreasing near colpi, colpi costate, costae 3um wide, lumina of reticulum slightly increasing toward mesocolpia, 0.7-0.9um wide. Specimens: PIN 39+166, 3.2 x 1 14.5; RE 143+120, 19.2 x 104 Discussion: Retibrevitricolpites distinctus Van Hoeken Klinkenberg, 1966 is smaller (13um), and lumina decrease toward mesocolpium, Retibrevitricolpites triangulatus Van Hoeken Klinkenberg, 1966 has a pore fastigiate, Retibrevitricolpites retibolus Leidelmeyer, 1966 is smaller (15-20um), and has a pore costate, Retibrevitricolpites "costatus" has a thicker exine (1.5um), lumina is finer (0.5um) and costae is narrower (2um). Retibrevitricolpites triangulatus Van Hoeken Klinkenberg, 1966 Fig. A16, 7-8 Diagnosis: Retibrevitricolporate, small-sized (17-26um), reticulate lumina decrease from equator to poles, colpi marginate, pore fastigiate, coarseness of sculpture is variable. Specimens: UR 812, 10.6 x 92.9; PIN 32+0, 17.9 x 102.9 Genus Retibrevitricolporites Legoux, 1978 Retibrevitricolporites "grandis" Fig. A-16, 9-10 Diagnosis: Retibrevitricolporate, mid-sized (26-50um), reticulate, lumina 0.5-0.9 wide, uniform, pore costate, when grain is degraded the sculpture appears scabrate or verrucate. Specimens: PINO, 14.9 x 1 1 1.5 PIN 81+0, 21.4 x 81 Discussion: Retibrevitricolporites "speciosus" does not have an uniform lumina.

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269 Retibrevitricolporites "speciosus" Fig. A-16, 11-13 Diagnosis: Retibrevitricolporate, small to mid-sized (21-30um), reticulate lumina decrease from equatorial intercolpial areas to poles and colpi, colpi marginate, pore costate, inner spherical body, coarseness of sculpture is variable. Specimens: N 354+120, 3.9 x 82.1 Discussion: Retibrevitricolpites distinctus Van Hoeken-Klinkenberg, 1966 is smaller (Bum), and tectum thickens around colpi, Retibrevitricolpites triangulatus Van HoekenKlinkenberg, 1966 has a pore vestibulate, and a colpi marginate by thickening of tectum. Genus Retidiporites Varma and Rawat, 1 963 Retidiporites elongatus Sarmiento, 1992 Fig. A-16, 14-15 Diagnosis: Retidiporate, ellipsoid, mid-sized (30um), pore simple, reticulate unevenly, lumina rounded, angular or fusiform, decreasing toward pores, semitectate, wide columellae. Specimens: N 1 10, 7.4 x 79.5 Retidiporites magdalenensis Van der Hammen and Garcia, 1966 Fig. A-16, 16 Diagnosis: Retidiporate, ellipsoid, mid-sized (27-40um), pore simple, evenly reticulate, tectate, coarseness of sculpture is correlated with grain size. Specimens: N 4, 18.6 x 95 Retidiporites "poricostatus" Fig. A-16, 17-19

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270 Diagnosis: Retidiporate, rectangular, mid-sized (42um), pore costate, unevenly foveoreticulate, coarser near pores, one grain found Specimens: N 45, 3.9 x 40.4 Discussion: Retidiporites magdalenensis Van der Hammen and Garcia, 1966 has a pore simple, and reticulum is evenly distributed, Retidiporites elongatus Sarmiento, 1992 has a lumina that decreases near pores. Genus Retimonocolpites Pierce, 1961 Retimonocolpites "ovatum" Fig. A16, 20-21 Diagnosis: Monosulcate, mid-sized (32-60um), trapezoidal with angular borders (egglike), micropitted densely, sometimes sparsely scabrate, colpus long with ends widely rounded, tectate, scabrate sculpturing is sometimes present. Specimens: NA 59+90, 6.6 x 83.5 Discussion: Retimonocolpites regio Van der Hammen and Garcia, 1966 has an ellipsoidal shape, has a margo, and sulcus end is pointed. Retimonocolpites splendidus Gonzalez 1967 is globular to ellipsoid, and exine is thicker (2.5um). Retimonocolpites regio Van der Hammen and Garcia, 1966 Fig. A16, 22-23 Diagnosis: Monosulcate, mid-sized (30-53um), micropitted, prolate, sulcus long and slightly marginate, tectate, exine thin, lumina 0.4-0.8um wide, margo sometimes is indistinct. Specimens: N 4, 7.6 x 85.3 Genus Retipollenites Gonzalez, 1967 Retipollenites "baculatus"

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271 Fig. A16, 24-25 Diagnosis: Inaperturate, mid-sized (40um), tectum 4um thick, reticulate, lumina 4-8um wide, muri 1.5um wide, nexine densely baculate, lum high, one grain found. Specimens: N 18, 14 x 82.7 Discussion: Spirosyncolpites spiralis Gonzalez, 1967 has a scabrate nexine, Retipollenites confusus Gonzalez, 1967 does not have a nexine densely baculate. Retipollenites "magnus" Fig. A16, 26-28 Diagnosis: Inaperturate, large-sized(lOOum), very thick tectum 8.5um, nexine micropitted, reticulate, simplicolumellate, very sparse columellae supporting the tectum, lumina 8-13um wide, muri 3um wide, one grain found Specimens: N 114, 12.3 x 110.5 Discussion: Spirosyncolpites spiralis Gonzalez, 1967 is smaller and nexine is scabrate, Retipollenites confusus Gonzalez, 1967 is smaller (48um), and exine is thinner (3um, reticulum only). Genus Retistephanocolpites Leidelmeyer, 1966 Retistephanocolpites angeli Leidelmeyer, 1966 Fig. A16, 29-30 Diagnosis: Retistephanocolpate, mid-sized (45-55um), colpi short, costate, reticulum uniform, lumina l-1.5um wide. Specimens: N 27, 20.3 x 101.2 Retistephanocolpites "fossulatus" Fig. A17, 1-3

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272 Diagnosis: Retistephanocolpate, mid-sized (30-55um), polygonal-obtuse-convex in polar view, colpi very short, indistinct, sculpture reticulate-foveolate at poles, fossulate at equator, exine thick, 6-8 colpate. Specimens: PIN 35+90, 15 x 94 PIN 42+100, 5.4 x 92.8 Discussion: Retistephanocolpites angeli Leidelmeyer, 1966 has longer colpi, Retistephanocolpites williamsi Germeraad et al, 1968 has a spongy exine, Retistephanocolporites festivus Gonzalez, 1967 has a protruding costa, and lumina is uniform (0.8um), Retistephanocolpites finalis Gonzalez, 1967 has a thinner tectum (2.5um), and lumina uniform (1.2um wide). Retistephanocolpites "gradatum" Fig. A17, 4-5 Diagnosis: Retistephanocolpate, mid-sized (40um), lumina decrease gradually from equator (lum) toward poles (<0.5um), colpi costate. Specimens: PIN 42+100, 20 x 1 10 Discussion: Retistephanocolpites angeli Leidelmeyer, 1966 has an uniform lumina (11.5um), Retistephanocolpites williamsi Germeraad et al, 1968 has an spongy exine, Retistephanocolporites festivus Gonzalez, 1967 has a protruding costa, and lumina is smaller and uniform. Retistephanocolpites "inciertus" Fig. A17, 6-7 Diagnosis: Retistephanocolpate, mid-sized (30um), colpi short, costate, lumina large (24um), angular, and uniform, one grain found. Specimens: PIN 52+1 10, 22.3 x 80.3 Discussion: Retistephanocolpites angeli Leidelmeyer, 1966 has a smaller lumina (11.5um), Retistephanocolpites williamsi Germeraad et al, 1968 has an spongy exine,

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273 Retistephanocolporites festivus Gonzalez, 1967 has a protruding costa, and lumina is smaller and uniform. Genus Retistephanocolporites Van der Hammen and Wijmstra, 1964 Retistephanocolporites festivus Gonzalez, 1967 Fig. A17, 8-9 Diagnosis: Retistephanocolporate, mid-sized (26-50um), colpi very short, pore costate, costa thick and protruding, reticulate lumina<1.0 um, tectate, thin exine, 4-6 colporate, a few grains are 3-colporate, lumen of reticulum 0.7-1.0um in diameter, pores size 2-6um. Specimens: PIN 42+100, 19.7 x 98.2; PIN 35+90, 7.6 x 1 1 1.4 Retistephanocolporites "fossulatus" Fig. A-17, 10-13 Diagnosis: Retistephanocolporate, mid-sized (24-28um), colpi very short, pore indistinct, costa non-protruding, reticulate/foveolate/fossulate on same grain, tectate 1.5um thick, sculpturing is variable in same grain. Specimens: PIN 28+0, 7.8 x 97.7 Discussion: Retistephanocolporites festivus Gonzalez, 1967 has a protruding costa, and lumina is smaller and uniform (0.8um), Retistephanocolpites finalis Gonzalez, 1967 has a thicker tectum (2.5um), a larger size (41-51um), and uniform lumina (1.2um wide). Genus Retistephanoporites Gonzalez, 1967 Retistephanoporites angelicus Gonzalez, 1967 Fig. A-17, 14-15 Diagnosis: Retistephanoporate, mid-sized (30um), pores simple, reticula uniform, circular, dense, lumina 0.9lum, 5-6 colpate Specimens: PIN 55+50, 11 x 113.5

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274 Retistephanoporites "crassiexinatus" Fig. A-17, 16-17 Diagnosis: Retistephanoporate, hexagonal, mid-sized (37um), exine semitectate thick (3.6um), nexine thick, one grain found Specimens: PIN 28+0, 5.2 x 85.6 Discussion: Retistephanoporites angelicus Gonzalez, 1967 has a thinner exine (1.7um), and ectexine is thicker than endexine, Retistephanoporites "minutipori" has smaller pores (lum), and thinner exine (1.5um). Retistephanoporites "minutipori" Fig. A-17, 18-19 Diagnosis: Retistephanoporate, mid-sized (26-35um), pores small, costate, reticula uniform, dense, lumina 0.9lum. Specimens: PIN 28+0, 1 1 .4 x 98. 1 Discussion: Retistephanoporites angelicus Gonzalez, 1967 has pores simple. Retistephanoporites "crassiexinatus" has a thicker exine (3.5um). Retistephanoporites "regaloi" Fig. A-17, 20-21 Diagnosis: Retistephanoporate, mid-sized (30um), pores lolongate, costate, reticula dense, lumina 0.4um, exine thin 0.8um, columellae indistinct, one grain found Specimens: La Paz 712m, 12.7x 107.9 Discussion: Retistephanoporites angelicus Gonzalez, 1967 has a exine thicker (1.7um), Retistephanoporites "crassiexinatus" has a exine thicker (3.5um), and lumina wider (11.5um).

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275 Genus Retisyncolporites Gonzalez, 1967 Retisyncolporites angularis Gonzalez, 1967 Fig. A-17,22 Diagnosis: Syncolporate, mimd-sized (40-46um), fossulate-low verrucate, thick exine (3.5um). Specimens: RE 241+40, 21.8 x 87.2; RE 251+30, 5.5 x 100 Retisyncolporites "complicatus" Fig. A17, 23-24 Diagnosis: Retisyncolporate, mid-sized (30um), colpi marginate by thinning of exine, poricostate, apocolpial field absent, tectate 1 .2 um thick, lumina of reticula <0.7um decreasing toward colpi, one grain found, degradation may give the impression of baculae in the mesocolpium as columellae loose tectum cover. Specimens: PIN 81+0, 3.1 x 95.1 Discussion: Syncolporites marginatus Van Hoeken Klinkenberg, 1964 has fossulae perpendicular to colpi and it is circular in polar view. Psilasyncolporites aureus Gonzalez, 1967 has a reticula that diminishes toward poles, and colpi is simple. Retisyncolporites "delicatus" Fig. A17, 25-27 Diagnosis: Retisyncolporate, mid-sized (40-50um), marginate, pore large, simple, lumina decrease toward colpi margo, margo width 2-4um. Specimens: PIN 12, 5 x 100.9; N 354+120, 1 1.6 x 85.3 Discussion: Syncolporites marginatus Van Hoeken Klinkenberg, 1964 is smaller (20um), poricostate, and has an uniform lumina, Retisyncolporites angularis Gonzalez, 1967 is fossulate-low verrucate, and has a thick exine (3.5um).

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276 Genus Retitricolpites Van der Hammen, 1956 ex Van der Hammen and Wijmstra, 1964 Retitricolpites absolutus Gonzalez, 1967 Fig. A18, 1-2 Diagnosis: Tricolpate, mid-sized (27um), subprolate, colpi short, costate, exine thick, tectate, psilate at equator passing transitional to foveolate-reticulate at poles, one grain found. Specimens: PIN 55+30, 4.8 x 104.4 Retitricolpites antonii Gonzalez, 1967 Fig. A18, 3-4 Diagnosis: Retitricolpate, mid-sized (26um), prolate, colpi long, simple, columellae barely distinct, tectate 1.5um thick, one grain found. Specimens: PIN 32+0, 14.2 x 107.9 Retitricolpites "baculensis" Fig. A18, 5-8 Diagnosis: Retitricolpate, mid to large-sized (50-70um), tectate exine, 7.8um thick, long columellae, reticulate, usually tectum is lacking given appearance of very dense baculae, when tectum is present muri 1.5 um wide, lumina 5-8 wide, younger grains have a more defined reticulum with muri being present over most of the surface Specimens: PIN 12, 6.5 x 106; N 74, 13,8 x 82.1; PIN 47+100, 13.2 x 83.2; PIN 81+0, 18,1 X 111,6 Discussion: Spirosyncolpites spiralis Gonzalez, 1967 has a well defined muri, a lower columellae density, and shorter columellae, Retitricolpites saturum Gonzalez, 1967 is smaller (40-47um), exine is thinner (3.2um), and lumina narrower (3.2um).

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277 Retitricolpites clarensis Gonzalez, 1967 Fig. A-18,9 Diagnosis: Retitricolpate; mid-sized (29-40um); finely reticulated (lumina 0.7lum); colpi simple, long; tectate, columella distinct, sculpturing looks fossulate when grain is deteriorated. Specimens: PIN 32+0, 12.4 x 97.6; N 265, 18.2 x 95.6; N 354+120M 7,5 X 89 Retitricolpites "costatus" Fig. A18, 10-11 Diagnosis: Retitricolpate; mid-sized (40um); micropitted densely (lumina <0.5um); colpi costate, columellae indistinct, one grain found. Specimens: PIN 71+0, 9.7 x 99.2 Discussion: Retitricolpites clarensis Gonzalez, 1967 has an uniform exine and colpi is simple, Retitricolpites belskii (Belski et al. 1968) Sarmiento, 1992 has colpi interangular, a dark stain in polar area, and is smaller (~25um), Retitricolpites "marginocostatus" is marginate, and columellae is distinct. Retitricolpites florentinus Gonzalez, 1967 Fig. A-18, 12-13 Diagnosis: Retitricolpate, mid-sized (40um), prolate, lumina l-1.5um wide at equator decreasing to 0.5um gradually toward poles, one grain found. Specimens: PIN 81+0, 9.1 x 89.1 Retitricolpites magnus Gonzalez, 1967 Fig. A-18, 14-15 Diagnosis: Retitricolpate, mid-sized (38-55um), lumina 3-4m wide, uniform, dense, muri

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278 thin, simplicolumellate, colpi simple, long. Specimens: PIN 32+0, 19.4 x 88.8 Retitricolpites "marginocostatus" Fig. A-18, 16-17 Diagnosis: Retitricolpate; mid-sized (40um); densely micropitted (lumina <0.6um); colpi costate and marginate by shortening of columellae. one grain found. Specimens: PIN 19+60, 11.9 x 113.7 Discussion: Retitricolpites clarensis Gonzalez, 1967 has an uniform exine and colpi is simple, Retitricolpites belskii (Belski et al. 1968) Sarmiento, 1992 has colpi interangular, a dark stain in polar area, and is smaller (~25um), Retitricolpites "costatus" is not marginate, and columellae is indistinct. Retitricolpites "peculiaris" Fig. A-18, 18-22 Diagnosis: Retitricolpate, mid-sized (38-55um), lumina large 6-10 m wide, muri thin, simplicolumellate, sometimes the muri is reticulate itself, colpi costate, short, complex intrareticulation is not always present. Specimens: NA 46, 17 x 101.6; NA 46, 22 x 91; NA 46, 1 1.5 x 96.5 Discussion: Retitricolpites marginatus Van Hoeken Klinkenberg, 1966 has a smaller lumina (3.5um) that decreases along colpi, Retitricolporites elegans Wijmstra, 1971 has pores, and lumina decreases toward poles and near colpi; Retitriporites "amplireticulatus" is porate, and muri is slightly wider (lum), Retitrescolpites catenatus Pocknall and Nichols, 1996 (1996)is smaller (24-33um), has a longer colpi extending almost to poles, exine thinner (2um), other species of Retitrescolpites Sah, 1967 have an etipila(ria)te exine.

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279 Retitricolpites perforatus Gonzalez, 1967 Fig. A18, 23-25 Diagnosis: Retitricolpate, mid-sized (32um), reticulate-foveolate-fossulate in same grain, lumina
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280 Specimens: PIN 42+100, 8.3 x 78.5 Discussion: Unique sculpturing in the Retitricolporites group. Retitricolporites cienagensis Duefias, 1980 Fig. A19, 7 Diagnosis: Tricolporate, mid-sized (26-3 lum), ectocolpi marginate, endopores costate, lumina decrease toward margo where is psilate, exine thickness decreases toward colpi. margo width 4-1.5um Specimens: PIN 35+90, 21 x 110 Retitricolporites "delicatus" Fig. A19, 8-9 Diagnosis: Tricolporate, mid-sized (28-35 um), spherical, pore costate, lalongate, conspicuous, colpi simple, thin, mid-sized, tectate thin, columella indistinct, micropitted." Specimens: PIN 52+1 10, 1 1 x 91.5 Discussion: Psilatricolporites maculosus Regali et al, 1974 has a continuous equatorial costae, Psilatricolporites "spongiosus" is subprolate, equatorial costa is very thick, and tectum spongy, Psilatricolporites transversalis Duenas, 1980 has a colpi shorter and indistinct, pores are protruding, it is psilate and subspherical, Retitricolporites "poricostatus" has a larger lumina (0.7 um), columellae distinct, and a shape triangularobtuse-convex. Retitricolporites "distinctus" Fig. A-19, 10-11 Diagnosis: Retitricolporate, mid-sized (35-4 lum), zonocolpate costate, meridional colpi very short and indistinct, lumina decreasing from equator to poles, distinctiveness of pores is variable.

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281 Specimens: N 120, 18.2 x 85.2 Discussion: Retitricolporites costatus Leidelmeyer, 1966 is smaller (25um) and has an uniform very fine reticula. Retitricolporites "grandis" Fig. A-19, 12-13 Diagnosis: Retitricolporate, mid-sized (40-52um), colpi marginate, pores costate, fastigiate, thin tectate, columellae indistinct, micropitted. Specimens: RE 67+120, 12.8 x 1 13 Discussion: Retitricolporites costatus Leidelmeyer, 1966 is smaller (25um) and has an uniform very fine reticula, Psilatricolporites marginatus Van der Kaars, 1983 has a marginate colpi, a smaller size (19-27um), and lack vestibula, Retitricolporites "vestibulatus" is smaller (23-40um), has a colpi simple, and columellae distinct. Retitricolporites guianensis Van der Hammen and Wymstra, 1964 Fig. A-19, 14-15 Diagnosis: Retitricolporate, mid-sized (28-40um), loose-meshed reticulate 3-4um wide, diminishing toward colpi, regularly distributed columellae, smaller grains with smaller lumina, some tricolpate. Specimens: PIN 32+0, 9.8 x 91 Retitricolporites hispidus Van der Hammen and Wymstra, 1964 Fig. A-19, 16 Diagnosis: Retitricolporate, mid-sized (22-36um), prolate, lumina <0.8um, pores and colpi costate, exine thick (2um). Specimens: PIN 39+166, 17.6 x 105

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282 Retitricolporites "insolitus" Fig. A-19, 17-18 Diagnosis: Retitricolporate, large-sized (60um), colpi long, simple, pores indistinct, tectate, nexine thick (2um), reticulate lumina 3.5-4.5um wide, angular, uniform, one grain found Specimens: PIN 81+0, 18.2 x 79.5 Discussion: Retitricolporites quadrosi Regali et al, 1974 has a colpi costate, and it is reticulate-foveolate. Retitricolporites irregularis Van der Hammen and Wymstra, 1964 Fig. A-19, 19 Diagnosis: Retitricolporate, mid-sized (23-5um), circular, reticulum muricostate, colpi and pores costate, coarseness of ornamentation is variable. Specimens: N 354+120, 7.3 x 103.8 Retitricolporites "longicolpis" Fig. A-19, 20-21 Diagnosis: Retitricolporate, mid-sized (40um), colpi long, pores circular, distinct, large (6um), nexine very thick (2um), sexine thin, columella distinct, thinning near colpi, fine reticulate, one grain found. Specimens: PIN 55+30, 7.3 x 89.5 Discussion: Retitricolporites "pachynexinatus" has a thicker nexine (3um) that diminish near colpi, and pores are indistinct. Retitricolporites "marginatus" Fig. A-19, 22-24

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283 Diagnosis: Retitricolporate, mid-sized (43-50um), ectocolpi marginate, lumina large (2um) in intercolpial equator decreasing toward margo where is micropitted and toward poles where lum wide. Specimens: PIN 28+0, 6 x 106.5 Discussion: Retitricolporites saskiae Gonzalez, 1967 has a reticulum finer toward equatorial area, Retitricolporites ellipticus Van Hoeken Klinkenberg, 1 966 has a colpi costate, Retitricolporites quadrosi Regali et ai, 1974 has a costate colpi, and exine is thicker (3um), Retitricolporites perpusillus Regali et ai, 1974 is smaller (28-36um), has a lumina intercolpate wider (3-4um) that abruptly decrease near colpi margin. Retitricolporites mariposus Leidelmeyer, 1966 Fig. A-20, 1-3 Diagnosis: Tricolporate, mid-sized (28um), triangular-acute-convex, micropittted, ectocolpi intruding, pore slightly costate, exine thinner near colpi. Specimens: N265, 13.7 x 109.1 Retitricolporites medius Gonzalez, 1967 Fig. A-20, 4 Diagnosis: Tricolporate, small to mid-sized (19-30um), subprolate, micropittted, ectocolpi intruding, pore simple, columellae distinct, exine l-1.5um. Specimens: N 354+120, 7.5 x 109.3 PIN 32+0, 19 x 91.5 Retitricolporites "minutus" Fig. A-20, 5-6 Diagnosis: Tricolporate, small to mid-sized (21-30um), subprolate, micropittted, ectocolpi costate, pore simple, columellae barely distinct. Specimens: PIN 39+166, 6.9 x 1 10.5

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284 Discussion: Retitricolporites medius Gonzalez ,1967 has a colpi simple, Retitricolporites squarrosus Van der Hammen and Wymstra, 1964 has a thicker exine (2um), distinct columella, and lumina wider (0.7um). Retitricolporites "pachynexinatus" Fig. A-20, 7-8 Diagnosis: Retitricolporate, mid-sized (25-36um), nexine very thick (3um) thinning near colpi, sexine thin, columella indistinct, fine reticulate. Specimens: PIN 42+100, 15.8 x 98.4 Discussion: Retitricolporites "longicolis" has a thinner nexine (2um) that do not diminish near colpi, pores distinct, and lumina is uniform. Retitricolporites "poricostatus" Fig. A-20, 9-11 Diagnosis: Tricolporate, small-sized (20-25um), reticula fine, ectocolpi simple, long, pore costate, columellae distinct. Specimens: N 354+120, 11.6x 107 Discussion: Retitricolporites costatus Leidelmeyer, 1966 has very short colpi, Retitricolpites cienagensis Duenas, 1980 is colpimarginate, Retitricolporites mariposus Leidelmeyer, 1966 has columellae decreasing in thickness toward colpi, lumina is smaller (<0.5um), exine is thicker (1.5um), and costa is narrower (lum). Retitricolporites squarrosus Van der Hammen and Wymstra, 1964 Fig. A-20, 12-13 Diagnosis: Tricolporate, small-sized (26um), subprolate, reticulate fine, lumina 0.7um, ectocolpi costate, pore simple, exine thick (2um). Specimens: PIN 35+90, 12.5 x 104.1

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285 Retitricolporites "tropicalis" Fig. A-20, 14-17 Diagnosis: Retitricolporate, mid-sized (24-30um), colpi costate, costae reduced at equator, pores indistinct, micropitted, columellae reduced near colpi, distinctiviness of lalongate pores is variable. m Specimens: N 74, 7.2 X 106.5 N 74, 6.5 X 85 Discussion: Retitricolporites crassicostatus Van Hoeken Klinkenberg, 1966 has a costa uniform, and columella thickness is constant. Retitricolporites "vestibulatus" Fig. A-20, 18-20 Diagnosis: Retitricolporate, mid-sized (23-40um), pore conspicuously costate and fastigiate, sculpture reticulate fine to psilate. Specimens: N 174, 6.4 x 83.8 Discussion: Retitricolporites costatus Leidelmeyer, 1966 is smaller (25um) and has an uniform very fine reticula, Psilatricolporites marginatus Van der Kaars, 1983 has a marginate colpi, a smaller size (19-27um), and lack vestibula. Genus Retitriporites Ramanujam, 1966 Retitriporites "amplireticulatus" Fig. A-20, 21-23 Diagnosis: Triangular-obtuse-convex, mid-sized (40um), triporate, pores indistinct, with a large simplicolumellate reticulum and a thick semitectate exine (2.8um) with distinct columellae, and muri lum wide, only one specimen. Specimens: N 1 10, 6.9 X 97.3

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286 Discussion: Retitriporites variabilis Muller, 1968 has indistinct columellae which tops are fused to a single structureless narrow band, and muri
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287 Specimens: PIN 35+90, 5.6 x 84.5 Discussion: Retitriporites typicus Gonzalez, 1967 is smaller (27-33um), spheroidal, and lumina size diminish toward equator. Retitriporites "perforatus" Fig. A-20, 30-31 Diagnosis: Retitriporate, pore costate and protruding, micropitted at equator, foveolate/fossulate at poles, tectate, exine thick (2um), one grain found Specimens: PIN 52+1 10, 5 x 87.5 Discussion: Retitriporites simplex Van der Kaars 1983 has a lumina uniform and pore simple, Retitriporites typicus Gonzalez, 1967 has a larger lumina (1.2um) that gradually decrease toward equator, sometimes sculptural elements are not fused. Retitriporites "poricostatus" Fig. A-20, 32-33 Diagnosis: Retitriporate, mid-sized (25-35um), costae distinct, slightly protruding, 3um thick, 4um wide, reticula uniform, angular, 1.5-2 wide, simplicolumellate. Specimens: PIN 71+0, 18.1 x 82 Discussion: Retitriporites federicii Gonzalez, 1967 has a lumina large (3um), thicker exine (2.3um), and muri broader (2um). Genus Rugotricolporites Gonzalez, 1967 Rugotricolporites felix Gonzalez, 1967 Fig. A-21, 1-2 Diagnosis: Retitricolporate, mid-sized (31um), prolate, rugulate, rugulae short, curved, colpi marginate. Specimens: PIN 28+0, 17.7 x 81.5

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288 Genus Scabrastephanocolpites Van der Hammen and Garcia, 1966 Scabrastephanocolpites "casanaris" Fig. A-2 1,3-4 Diagnosis: Scabrastephanocolporate, mid-sized (40um), colpi short, marginate, atectate 0.5um thick, one grain found. Specimens: N 265, 20 x 102 Discussion: Scabrastephanocolpites vanegensis Van der Hammen and Garcia, 1966 has a larger colpi (14/37um) and margo is less distinct, Scabrastephanocolpites scabratus Van der Hammen and Garcia, 1966 is tectate, Scabrastephanocolpites guadensis (Van der Hammen, 1954) Sarmiento, 1992 has a thicker exine (2um). Genus Scabratricolporites Van der Hammen, 1956 ex Poche and Schuler, 1976 Scabratricolporites "amplocolpatus" Fig. A-2 1,5-7 Diagnosis: Scabratricolporate, prolate, mid-sized (32-44um), atectate, colpi long, costate, pores lalongate, costate, porecosta 2-3um wide, surrounding partially or entirely the pore. Specimens: UR 812, 10.5 x 91.5; UR 812, 14.2 x 103.9; UR 531+120, 10.5 x 82.8 Discussion: Scabratricolporites platanensis Duenas, 1980 has colpi and pores simple, Scabratricolporites "tomassoi" is tectate and costae of pores is narrower (lum). Scabratricolporites "tomassoi" Fig. A-2 1,8-9 Diagnosis: Scabratricolporate, small-sized (20-25um), tectate, colpi long, costate, pores lalongate, costate. Specimens: PIN 42+100, 11.9 x 103

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289 Discussion: Scabratricolporites platanensis Duenas, 1980 has colpi and pores simple, Scabratricolporites "amplicolpatus" is atectate and costae of pores is wider (3um). Genus Scabratriporites Van der Hammen 1956 ex Van Hoeken Klinkenberg, 1964 Scabratriporites "bellus" Fig. A-21, 10-11 Diagnosis: Scabratriporate, mid-sized (36um), annulate, annuli 3-4um wide/2um thick, atectate (0.5um), scabrae <0.5um wide/high, one grain found Specimens: RE 251+30, 5.1 x 98.2 Discussion: Scabratriporites simpliformis Van Hoeken Klinkenberg, 1966 is smaller (21um), annuli is thinner (1.2um), and amb is triangular-convex, Cricotriporites "macropori" has a wider circular pore (5-9um) and annuli is thinner (lum). Genus Spinizonocolpites Muller, 1968 Spinizonocolpites "brevibaculatus" Fig. A-21, 12-14 Diagnosis: Zonocolpate, mid-sized (32-50um), tectate (l-2um thick), tectum finely reticulate, lumina
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290 Diagnosis: Spinizonocolpate, mid to large-sized (40-65um), tectate (1 um thick), tectum micropitted, echinate, spines 2-4um long, l-2um wide, 3-5um apart, cylindrical to subconical, , spines height is relatively constant within same grain. Specimens: N 1 10, 14.8 x 1 10.2 N 74, 8.2 x 95 Discussion: Spinizonocolpites echinatus Muller, 1968 is very similar but spines are significateiy larger (5-7um), wider, more spaced from each other, and conical with lower part slightly expanded, Spinizonocolpites "grandis" has wider spines (3-4um wide), longer (4-5um high), and conical. Spinizonocolpites "grandis" Fig. A-21, 18-20 Diagnosis: Spinizonocolpate, large-sized (7085um), tectate (1 um thick), tectum finely reticulate, echinate, spines 4-5um long, 3-4um wide, 5-10um apart, conical, spines height and shape are relatively constant within same grain. Specimens: PIN 12, 1 1.4 x 1 1 1.2 Discussion: Spinizonocolpites echinatus Muller, 1968 is smaller (33-43) and has spines larger (5-7um), Spinizonocolpites "breviechinatus" has narrower spines (l-2um wide), shorter (2-4um high), and subconical to cylindrical. Spinizonocolpites "pachyexinatus" Fig. A-21, 21-22 Diagnosis: Spinizonocolpate, large-sized (70-80um), tectate thick (3-5um thick), tectum micropitted to finely reticulate, lumina <0.7um, echinate, spines 7-10 long, 10-20 um apart, often slightly expanded at the base, spines hollow to massive, psilate to micropitted, tectum micropitted to finely reticulated. Specimens: N 174, 13 x 108

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291 Discussion: Spinizonocolpites echinatus Muller, 1968 is similar but exine is thinner (2um) and spines shorter (5-7um). Spinizonocolpites "pluribaculatus" Fig. A-22, 1-2 Diagnosis: Zonocolpate, mid-sized (55um), tectate thick(3um thick), columellae barely distinct, tectum micropitted, baculae 4-6 long, 2-6 um apart, one grain found, baculae shape variable is same grain, (reworked?) Specimens: UR 761, 17.5 x 92.3 Discussion: Spinizonocolpites baculatus Muller, 1968 is similar but exine is thinner (12um) and has longer baculae (7Bum), Spinizonocolpites "brevibaculatus" has a thinner tectum (l-2um), tectum is finely reticulate, and baculae is more scattered (7-12um apart). Genus Spirosyncolpites Gonzalez, 1967, emend. Legoux, 1978 Spirosyncolpites spiralis Gonzalez, 1967 Fig. A-22, 3-5 Spirosyncolpites spiralis Gonzalez, 1967, p. 45, pi. 16, figs. 1-lc. Retitricolpites amapaensis Regali et ai, 1974, p 280, pi. 17, fig. 4. Diagnosis: Retitricolpate, mid to large-sized (32-85um), colpi often indistinct, exine tectate 9um thick, reticulate, lumina 8um-14um wide, muri 1.2um wide, simplibaculate, nexine scabrate. Specimens: PIN 81+0, 17.9 x 104.5; PIN 32+0, 19 x 101.8 Discussion: The holotype of Retritricolpites amapaensis Regali et ai, 1974 was observed and correspond to this species. Genus Striatricolpites Van der Hammen, 1956 ex Gonzalez, 1967 Striatricolpites catatumbus Gonzalez, 1967

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292 Fig. A-22, 6-7 Diagnosis: Striatricolp(or)ate, prolate, mid-sized (37-53um), colpi simple, long, intruding, pore indistinct, tectum thick, 2.5um thick, muri subparallel to slightly anastomosing, lum high, lum apart, 1-1. 5um wide, coarseness of wall is variable as well as presence of pores. Specimens: PIN 66+80, 15.6 X 108.5 Striatricolpites minor Wijmstra, 1971 Fig. A-22, 8 Diagnosis: Striatricolpate, subprolate, small-sized (15-1 8um), colpi simple, long, pores k absent or indistinct, tectate, exine thin, 0.8um thick, muri subparallel to colpi, 0.3um high, <0.5um apart, <0.5um wide, one grain found Specimens: N 120, 11.9x 115.1 Striatricolpites "orinocus" Fig. A-22, 9-10 Diagnosis: Striatricolpate, prolate, mid-sized (35-4 lum), colpi simple, long, tectum thin, exine lum thick, muri parallel to colpi, 0.4um high, 0.5-0.7 urn apart, 0.8um wide, tectum reticulate within striae. Specimens: N 74, 5 x 96.6 Discussion: Striatricolpites catatumbus Gonzalez, 1967 has a thicker exine (3um) and wider muri (l-1.5um), Striatricolpites semistriatus Gonzalez, 1967 has muri bifurcating at the poles, Striatricolpites saramacensis Wijmstra, 1971 has a thicker exine (2-3um), Striatricolporites tenuissimus Duenas 1980 has a colpi costate, Striatricolporites agustinus Gonzalez 1967 is smaller (19-23um), Striatricolporites pimulis Leidelmeyer, 1966 has a endopore annulate, and exine diminishes near colpi.

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293 Striatricolpites "tenuistriatus" Fig. A-22, 11-13 Diagnosis: Striatricol(por)ate, prolate, mid-sized (36-45um), colpi costate, long, pore, when present, lolongate and costate, striae and muri 0.5um wide, muri <0.5 high, meridionally elongated, exine thin, 0.8um thick, columella indistinct, a few grains are tricolporate. Specimens: RE 143+120, 15.6 x 95.2; UR 812, 17.8 x 89.4 Discussion: Striatricolpites catatumbus Gonzalez, 1967 has a thicker exine (3um) and wider striae (1.5um), Striatricolpites semistriatus Gonzalez, 1967 has a thicker exine (1.5um) and striae bifurcate at the poles, Striatricolpites saramacensis Wijmstra, 1971 has a thicker exine (2-3um) and columellae distinct, Striatricolporites tenuissimus Duenas, 1980 is reticulate within striae (lumina 0.5-0.8um wide), Striatricolporites agustinus Gonzalez, 1967 is smaller (19-23um). Genus Striatricolporites Leidelmeyer, 1966 Striatricolporites "digitatus" Fig. A-22, 14-15 Diagnosis: Striatricolporate, prolate, mid-sized (35um), colpi costate, long, pore indistinct, muri pattern resembles a finger print, exine tectate, lum thick, columella distinct, one grain found. Specimens: N 21+100, 16x101.9 Discussion: Striatricolpites catatumbus Gonzalez, 1967 has a thicker exine (3um), wider muri (1.5um), subparallel, Striatricolpites semistriatus Gonzalez, 1967 has muri bifurcating at the poles, Striatricolpites saramacensis Wijmstra, 1971 has a thicker exine (2-3um) and muri parallel, Striatricolporites tenuissimus Duenas, 1980 is reticulate within striae (lumina 0.5-0.8um wide), Striatricolporites agustinus Gonzalez, 1967 is smaller (19-23um) and muri parallel, Striatricolporites pimulis Leidelmeyer, 1966 has a

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294 endopore annulate, and exine is thinning near colpi, Dactylopollis Muller, 1968 is colpate, foveolate-reticulate in intercolpate equatorial areas and curved-striate along colpi and near poles. Striatricolporites "reticulatus" Fig. A-22, 16-17 to > Diagnosis: Striatricolpate, prolate, mid-sized (25-36um), colpi costate, pores costate lalongate, exine thick, 1 .5-2um thick, striations very faint and randomly organized, overlying a tectum finely reticulate distinctiveness of costae of colpi is variable. Specimens: N 149, 19x91 Discussion: Striatricolpites catatumbus Gonzalez, 1967 has a thicker exine (3um) and higher muri (lum), Striatricolporites tenuissimus Duefias, 1980 has a thinner exine (lum) and pore simple, Striatricolporites pimulis Leidelmeyer, 1966 has a exine that diminishes near colpi, Striatricolporites "orinocus" has thinner exine (0.8um) and reticula is less uniform. Genus Syncolporites Van der Hammen, 1954 Syncolporites lisamae Van der Hammen, 1954 Fig. A-22, 18-19 Diagnosis: Syncolporate, small-sized (16-2 lum), pore annulate, apocolpial field absent, scabrate, psilate in annuli zone, intectate (<0.5um thick), one grain. Specimens: N 87, 1 1 .4 x 84. 1 Syncolporites marginatus Van Hoeken Klinkenberg, 1964 Fig. A-22, 20-21 Diagnosis: Retisyncolporate, small-sized (20um), colpi marginate, pore costate, lumina

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295 0.7um, dense, uniform. Specimens: RE 113, 11.5 x 109.4 Syncolporites "verrucatus" Fig. A-22, 22-23 Diagnosis: Syncolporate, small-sized (17um), verrucate, verrucae l-1.3um wide, lum high, colpi simple, pores annulate, one grain found. Specimens: N 174, 12.2 x 114 Discussion: Syncolporites lisamae Van der Hammen, 1954 is scabrate to microverrucate (<0.5um high). Genus Ulmoideipites Anderson, 1960 Ulmoideipites krempii (Anderson, 1960) Elsik, 1968b Fig. A-22, 24 Ulmoideipites krempii Anderson, 1960, p. 20, pi. 4, fig. 12; pi. 6, figs. 2-3,: pi. 10, fig. 8 Verrustephanoporites simplex Leidelmeyer, 1966, p. 55, pi. 3, fig. 10; pi. 4, fig. 2 Ulmoideipites krempii (Anderson, 1960) Elsik, 1968b, p. 608, pi. 17, figs 4-7. Diagnosis: Stephanoporate, 3-5-porate, mid-sized (26-35um), annulate, arcuate (arci faint to distinct), verrucate, exine thin (0.8um), tectate, verrucate height is variable. Specimens: N 149, 18.6x96.9 Genus Verrustephanocolpites Van der Hammen and Garcia, 1966 Verrustephanocolpites "rugulatus" Fig. A-22, 25 Diagnosis: Stephanocolpate, mid-sized (34-38um), colpi short, surrounded by 2 ridges, 1.5-2.5um high, verrucate to rugulate, intectate, each pair of ridges can be 6um to lum apart, mesocolpium and apocolpium sculpture from verrucate to rugulate.

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296 Specimens: N 265, 18.2 x 109.2 Discussion: Ctenolophonidites Van Hoeken Klinkenberg, 1966 has endexinous thickenings fusing at the poles forming a ring, Cristatricolpites analemae Leidelmeyer, 1966 has a columellae distinct, and it is psilate. Genus Verrustephanoporites Leidelmeyer, 1966 Verrustephanoporites "gemmatus" Fig. A-22, 26-27 Diagnosis: Stephanoporate, mid-sized (29um), pore costate, lalongate, tectate, columellae indistinct, microverrucae densely, with scattered microgemmae, microbaculae, and microclavae, one grain found. Specimens: PIN 52+1 10, 4.3 x 104 Discussion: Gemmastephanoporites breviculus Gonzalez, 1967 is larger (34-40um), gemmae is higher (l.lum) and wider (l.l-1.3um), and tectum is reticulate, Verrutricolporites "reticulatus" is larger (31-57um), has colpi very short, verrucae 1-1.5 wide/0.5 high, and densely micropitted, Scabrastephanoporites "lolongatus" has lolongate pores, and sculpture is shorter (<0.5um). Genus Verrutricolpites Pierce, 1961 Verrutricolpites "irregularis" Fig. A-22, 28-29 Diagnosis: Verrutricolpate, mid-sized (33um), colpi very long, marginate, margo protruding, verrucae rounded to angular, irregularly shaped, 0.5um high, one grain found Specimens: PIN 81+0, 8.8 x 87.2 Discussion: Verrutricolpites isolatus Leidelmeyer, 1966 has a colpi simple and verrucae is higher (3-3.5um).

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297 Genus Verrutricolporites Van der Hammen and Wijmstra 1964, emend. Legoux, 1978 Verrutricolporites "reticulatus" Fig. A-22, 31-33 Diagnosis: Verrutriporate, mid-sized (31-57um), pore costate, large (4-10um wide), verrucae 1.5-2 wide/0.5lum high, densely micropitted to finely reticulated, 3-4 colporate, colpi often lacking. Specimens: PIN 66+80, 21.5 x 104; PIN 52+1 10, 10.5 x 98; PIN 81+0, 19 x 103; PIN 81+0, 7.6 x 105.5. Discussion: Gemmastephanoporites breviculus Gonzalez, 1967 is gemmate. Genus Wilsonipites Srivastava, 1969 Wilsonipites margocolpatus Mullere/fl/., 1987 Fig. A-22, 30 Diagnosis: Tricolporate, micropittted, mid-sized (30um), colpi very long, almost syncolpate, marginate. Specimens: RE 132, 6.4 x 102.3 Genus Zonocostites Germeraad et al, 1968 Zonocostites "minor" Fig. A-22, 34-36 Diagnosis: Psilatricolporate, small-sized (12-15um), prolate to subprolate, equatorial aperture elongated to fused, costate, slightly fastigiate, micropitted, to almost psilate at equator, coarseness of structure and perforations at the poles are variable. Specimens: PIN 52+1 10<10, 6.5 x 97.9; PIN 52+1 10<10, 8.4 x 92; PIN 52+1 10NO, 15.4 x97.5

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298 Discussion: Zonocostites ramonae Germeraad et al, 1968 is very similar but consistently larger (16-1 9um) and subprolate to circular, Zonocostites duquensis Duenas, 1980 has a clear reticulation. DINOFLAGELLATE CYSTS Phylum PYRRHOPHYTA Pascher, 1914 Class DINOPHYCEAE Fritsch, 1929 Order PERIDINIALES Haeckel, 1894 Genus Achomosphaera Evitt, 1963 Achomosphaera sp. A Fig. A-23, 1-2 Diagnosis: Spiniferites-type with no septa connecting process bases, wall psilate, body spherical, processes gonal and intergonal bifurcating or irifurcating more than once. Size (50-60um) Specimens: PIN 12, 6.4 x 94 Discussion: This genus has a large intraspecific morphological variation. Genus Cordosphaeridium Eisenack, 1963 Cordosphaeridium sp. A Fig. A-23, 3-7 Diagnosis: Cordosphaeridium-lypz, processes intratabular, fibrous, open distally, wall finely reticulate, Size (60-100um). Specimens: PIN 12, 10.5 x 102.5; PIN 12, 4 x 95.2 ;PIN 47+100, 20.6 x 95.7 Discussion: preservation of few cysts available preclude species assignment Genus Coronifera Cookson and Eisenack, 1958 Coronifera sp. A

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299 Fig. A-23, 8-9 Diagnosis: Skolochorate, with multiple nontabular processes closed distally and a single large antapical process open distally, one cyst found. Specimens: N 174, 13.1 x 80 Discussion: preservation of cyst available precludes species assignment Genus Glaphyrocysta Stover and Evitt, 1978 Glaphyrocysta sp. A Fig. A-23, 10-12 Diagnosis: Glaphyrocysta-type, provess complexes with many branched stalks, joined by a simple, slender trabeculae, wall between processes finely reticulate, lumina <0.6um, two cysts found Specimens: PIN 35+90, 18.4 x 104.3 Discussion: Large intraspecific variation in this genus. Genus Homotryblium Davey and Williams, 1966 Homotryblium floripes (Deflandre and Cookson, 1955) Stover, 1975 Fig. A-23, 13-15 Diagnosis: Skolochorate, AP: A(3A)6P, processes long, intratabular, size (70-100um) Specimens: PIN 28+0, 1 1.3 X 90.1 Genus Hystrichosphaeridium Deflandre, 1937 Hystrichosphaeridium sp. A Fig. A-24, 1-5 Diagnosis: Skolochorate, processes intratabular, parasutural ridges, parasulcus and paracingulum indicated by processes, size (60-70um). Specimens: PIN 28+0, 12 x 107; PIN 52+1 10, 20 x 80.8

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300 Discussion: Unique in having a distinct parasutural ridges that defines a complete paratabulation. Also it shows a Hystrichosphaeridium species with sexiform hypocyst. Genus Lingulodinium Wall, 1967 Lingulodinium cf. sicula (Drugg, 1970) Wall and Dale in Wall etal, 1973 Fig. A-24, 6-7 Diagnosis: Operculodinium-type, processes nontabular, subconical, closing distally, acuminate to evexate, size (50-60um) Specimens: PIN 35+90, 10.3 x 92.2 PIN 52+1 10, 15.7 x 103 Discussion: Cysts fit description of L. siculum, although archeophyle type could not be determined. Genus Nematosphaeropsis Deflandre and Cookson, 1955 Nematosphaeropsis sp. A Fig. A-24, 8-10 Diagnosis: Skolochorate, intermediate-sized, parasutural process tips connected by a network of ribbon-like trabeculae, size (60-90um). Specimens: PIN 12, 18.6x82 Discussion: preservation of cyst available precludes species assignment Genus Polysphaeridium Davey and Williams, 1966 Polysphaeridium sp. A Fig. A-24, 11-12 Diagnosis: Skolochorate, AP: A(3A)6P, processes long, narrow, cylindrical and nontabular, size (55-68um) Specimens: PIN 12, 6.1 x 114.9 Discussion: large intraspecific variation in this genus.

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301 Genus Senegalinium Jain and Millepied, 1973 Senegalinium sp. A Fig. A-24, 13-14 Diagnosis: Deflandrea-type, circumcavate, endophragm psilate, periphragm slightly scabrate with longitudinal folds popericoel, wall psilate, processes gonal and intergonal, one cyst found. Specimens: UR 726, 9.8 x 107.3 Discussion: very similar to S. mirabilis, but archeophyle could not be determined. Spiniferites sp. A Fig. A-25, 3-4 Diagnosis: Spiniferites-like, 60um, with wall finely reticulate Specimens: PIN 12, 17.8 x 98.9 Discussion: Large intraspecific variation in this genus. Genus Systematophora Klement, 1960 Systematophoral sp. A

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302 Fig. A-25, 5-6 Diagnosis: Proximochorate, processes 5-6um long, densely distributed, subconical to tapering, occasionally two or more processes joined at the base by a ridge seeming arcuate penitabular complexes, wall between processes finely reticulate, one cyst found Specimens: PIN 28+0, 12.5 x 83.6 Discussion: The archeophyle type could not be determined, also it is not clear if the processes are grouped in arcuate penitabular complexes. This data would confirm its affinity to Systematophora Klement 1960. INCERTAE SEDIS GROUP Incertae sedis A Fig. A-23, 16-17 Diagnosis: Rhombic psilate grain, with a thin wall that thickens at the vertices of the grain, thickness of the wall (0.7-1.2um), size (50-60um). Specimens: PIN 42+100, 23 x 95.4 Discussion: Probably a type of Zygnemataceae, genus Mougeotia.

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Figure A-l. Illustration of palynomorphs Bar scale=10um for Figures A-l to Aprv=proximal view,dv=distal view, ev=equatorial view, pv=polar view, lv=lateral view hf=high focus, mf=mid focus, lf=low focus tax a CI7A f c\r\ l < vi<*w v it w M 1 UL ronrHptmtpc LWl UCl la LCD i Dacuiaiispontes irregularis 98 x 95 hf 1 1 1 nrv PIN 75+160 4 f> y 8S S z oacuiatisporiies liic^uuuis 98 x 95 ZO A ZJ mf Ul V PIN 7 5+1 (SO A f\ v 8S S H.\J A OJ.J 3 Baculatisporites "irregularis ' 98 y 9S ZO A ZJ If prv PIN 7S+1 fifl H.O A OJ.J 4 Baculatisporites "soleus" 98 y 98 ZO A ZO hf ill prv PIN 49+1 on r 11Y HZ+ 1 yj\J ^ f\ y 1 no 7 J.O A 1U7. / 5 Baculatisporites "soleus" 98 y 98 ZO A ZO mf 1111 prv PT1M 49+1 nn s (\ y 1 no 7 J.O X 1UV. / 6 Baculatisporites "soleus" 98 v 98 ZO X Zo If 11 prv PTM 49 j. 1 flfl r 1IN 4Z+ J UU ^ A v I no 7 j.o x iuy. / 7 Camarozonosporites "inciertus" LI X LI ni prv I TD 0 17 UK 61Z 1 7 O v 117 1 1 J.y X 1 1Z.1 8 Camarozonosporites "inciertus" LI X LI mi prv I ip o 1 o UK 61Z 1 7 O v 117 1 i j.y x i iz. i 9 Camarozonosporites "inciertus" 77 v 77 LI X LI i f it prv iin 0 17 UK olz 1 7 O v 117 1 l j.v x 1 1 z. i 10 Chomotriletes minor 70 v 1 c JO X jj mi prv DIM 7/1 j £fl rilN Z4+0U 1 7 O v OA C i /.y x o6.j 1 1 Cicatricosisporites dorogensis A~l v A A 4 / X 44 nr av rilN zo+U O 1 v QQ £ 0. 1 X 00. J 1 2 Cicatricosisporites dorogensis 47x44 mf dv PIN 28+0 8.1 x 88.5 1 3 Cicatricosisporites dorogensis 47x44 If dv PIN 28+0 8.1 x 88.5 14 C. dorogensis subsp. minor forv. rugulatearis 57x60 hf dv PIN 12 12x 101.7 1 5 C. dorogensis subsp. minor forv. rugulatearis 57x60 mf dv PIN 12 12 x 101.7 1 6 C. dorogensis subsp. minor fan: rugulatearis 57x60 If dv PIN 12 12 x 101.7 17 Cicatricosisporites "infrafoveolatus" 40 x 37 hf dv N 18 4 x 86.7 1 8 Cicatricosisporites "infrafoveolatus" 40x37 mf dv N 18 4 x 86.7 19 Cicatricosisporites "infrafoveolatus" 40 x 37 If dv N 18 4 x 86.7 20 Cicatricososporites "decussatus" 57x34 hf Iv PIN 55+30 5.4 x 92.3 21 Cicatricososporites "decussatus" 57x34 mf lv PIN 55+30 5.4x92 3 22 Cicatricososporites "decussatus" 57x34 If Iv PIN 55+30 5.4x92.3

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Figure A-2. Illustration of palynomorphs see key to labels in Figure A1 tax a size focus view slide coordenates 1 Cicatricososporites eocenicus 55 x 35 hf lv PIN 52+110 6x 102.6 2 Cicatricososporites eocenicus 60 x 40 hf prv PIN 28+0 17.6 x 110 3 Clavatisporites mutisi 31 x 25 hf prv N 87 14.1 x 85.5 4 Clavatisporites mutisi 31 x 25 mf prv N 87 14.1 x 85.5 5 Echinatisporis "brevispinosus" 30 x 26 hf dv PIN 81+0 9.4 x 84.5 6 Echinatisporis "brevispinosus" 30 x 26 mf dv PIN 81+0 9.4 x 84.5 7 Echinatisporis ? cingulatus 26 x 25 hf dv PIN 52+110 10.6 x 108.4 8 Echinatisporis 1 cingulatus 26 x 25 mf dv PIN 52+110 10.6 x 108.4 9 Echinatisporis ? "cingulatus" 26x25 If dv PIN 52+110 10.6 x 108.4 10 Echinatisporis microechinatus 27 x 25 hf dv PIN 19+60 19.1 x 88.2 1 1 Echinatisporis "microechinatus" 27x25 mf dv PIN 19+60 19.1 x 88.2 12 Echinatisporis "microechinatus" 27 x 25 If dv PIN 19+60 19.1 x88.2 13 Echinatisporis "obscurus" 34x34 hf prv N 110 21.2x92.1 14 Echinatisporis "obscurus" 34x34 mf prv N 110 21.2x92.1 15 Echinatisporis "obscurus" 30 x 25 If dv N 110 3.6x91.9 16 Echinatisporis "portae" 24 x 20 hf dv PIN 28+0 5.2x87.1 17 Echinatisporis "portae" 24 x 20 mf dv PIN 28+0 5.2 x 87.1 1 8 Echinatisporis portae 24 x 20 If dv PIN 28+0 5.2x87.1 19 roveotnletes fossulatus 35 x 34 hf prv PIN 81+0 12.2 x 112.8 20 roveotnletes fossulatus 35 x 34 If prv PIN 81+0 12.2 x 112.8 21 roveotnletes fossulatus 30 x 28 If dv PIN 52+1 10 5x 82.3 22 roveotnletes fossulatus 30 x 28 mf dv PIN 52+110 5x 82.3 23 roveotnletes margantae 40x36 hf dv PIN 63+20 17.6 x 106 24 Foveotriletes margaritae 40 x 36 mf dv PIN 63+20 17.6 x 106 25 Ischyosporites "problematicus" 38x32 hf dv N265 12 x 1 14 26 Ischyosporites "problematicus" 38x32 mf dv N265 12 x 114 27 Ischyosporites "problematicus" 38x32 If dv N265 12x114 28 Ischyosporites "problematicus" 40x40 If dv N 110 13.9x85.6 29 Kirchheimerisporites "tenuiradiatus" 27x25 mf prv PIN 55+30 5.1 x99.5 30 Kirchheimerisporites "tenuiradiatus" 27x25 If prv PIN 55+30 5.1 x 99.5 31 Laevigatosporites "barcoi" 33x25 If lv NA 46 lOx 108.1 32 Laevigatosporites "barcoi" 33x25 mf lv NA46 lOx 108.1 33 Laevigatosporites "barcoi" 33x25 hf lv NA 46 10 x 108.1

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306

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Figure A-3. Illustration of palynomorphs see key to labels in Figure A-l taxa size focus view 1 * J slide coordenates 1 Laevigatosporites "tenuiexinatus" 50x36 hf prv PIN 28+0 15.5 x 93 2 Laevigatosporites "tenuiexinatus" 50x36 mf prv PIN 28+0 15.5 x 93 3 Laevigatosporites "tenuiexinatus" 50 x 36 If prv PIN 28+0 15.5 x 93 4 Laevigatosporites tibui 41 x 35 mf lv XT Ail 1 f\f\ N 21+100 6.6 x 91 5 Microfoveolatosporis skottsbergii 89 x 50 mf lv RE 67+ 1 20 6.8 x 92.3 6 Microfoveolatosporis skottsbergii 60 x 42 mf lv PIN 8 1 +0 13.2 x 112 1 Osmundacidites "dispergatus" 30 x 26 hf prv N 18 7.9 x 105 8 Osmundacidites "dispergatus" 30x26 mf prv N 18 7.9 x 105 9 Osmundacidites "dispergatus" 30 x 26 If prv N 18 7.9 x 105 10 Osmundacidites "minor" 26 x 25 hf dv PIN 63+20 14.8 x 87.4 1 1 Osmundacidites "minor" 26x25 mf dv PIN 63+20 14.8 x 87.4 12 Osmundacidites "minor" 26x25 If dv PIN 63+20 14.8 x 87.4 13 Polypodiaceoisporites ? "fossulatus" 40 x 33 hf dv La Paz 886m 20.7 x 80.5 14 Polypodiaceoisporites ? "fossulatus" 40 x 33 mf dv La Paz 886m 20.7 x 80.5 15 Polypodiaceoisporites ? "fossulatus" 40x33 If dv La Paz 886m 20.7 x 80.5 16 Polypodiaceoisporites ? "fossulatus" 38x37 hf prv PIN 52+110 6.7 x 112 17 Polypodiisporites "ore vis" 26x24 hf lv UR 531+20 14.8 x 110.7 18 Polypodiisporites "brevis" 26x24 mf lv UR 531+20 14.8 x 110.7 19 Polypodiisporites "breviverrucatus" 50x35 hf lv La Paz 712m 17.6 x 106.5 20 Polypodiisporites "breviverrucatus" 50x35 mf lv La Paz 712m 17.6 x 106.5 21 Polypodiisporites "breviverrucatus" 50x35 If lv La Paz 7 1 2m 17.6 x 106.5 22 Polypodiisporites "densus" 43x32 hf prv PIN 81+0 16.6x90 23 Polypodiisporites "densus" 43x32 mf prv PIN 81+0 16.6x90 24 Polypodiisporites "densus" 43x32 If prv PIN 81+0 16.6x90

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Figure A-4. Illustration of palynomorphs see key to labels in Figure A1 taxa size focus view slide coordenates 1 Polypodiisporites "echinatus" 4U X 3U Uf nt IV M ~IA IN /4 I C < «r 1 AO C Ij.j X IUo.j 2 Polypodiisporites echinatus 40 x 30 mf lv N 74 15.5 x 108.5 3 Polypodiisporites "echinatus" 40 x 30 It lv XT 1 A N 74 15.5 x 108.5 4 Polypodiisporites pachyexinatus 45 x 30 hf prv N 174 8.2 x 92 5 Polypodiisporites "pachyexinatus" a c in 45 x 30 mt prv xt N 174 8.2 x 92 6 Polypodiisporites "pachyexinatus" 45 x 30 It prv XT 1 T A N 174 8.2 x 92 7 Polypodiisporites "protousmensis" 50 x 30 mt lv XI ^ 1 . 1 f\f\ N 21+100 11.6x98.8 8 Polypodiisporites "protousmensis" 50 x 30 If lv N 21+100 11.6 x 98.8 9 Polypodiisporites specious 40 x 28 If lv PIN 75+0 10.2 x 78.7 10 Polypodiisporites specious 40 x 28 mf lv PIN 75+0 10.2 x 78.7 1 1 Pteridacidites "cucutensis" 42 x 28 hf dv La Paz 712m 15 x 88.4 12 Pteridacidites "cucutensis" 40 x 32 hf prv La Paz 886m 8.2 x 78.3 13 Pteridacidites "cucutensis" 40 x 32 If prv La Paz 886m 8.2 x 78.3 14 Retitriletes "enigmaticus" 60 x 50 hf dv PIN 66+80 5.5 x 84.2 15 Retitriletes enigmaticus 60 x 50 mf dv nt\T f s , on PIN 66+80 5.5 x 84.2 16 Retitriletes "enigmaticus" 60x50 If dv PIN 66+80 5.5 x 84.2 17 Tuberositriletes? "inciertus" 26x26 hf prv N 354+120 15 x 107.7 18 Tuberositriletes? "inciertus" 26x26 mf prv N 354+120 15 x 107.7 19 Tuberositriletes? "inciertus" 26x26 If prv N 354+120 15 x 107.7 20 Tuberositriletes "verrucatus" 30 x 27 hf prv PIN 12 10x94.9 21 Tuberositriletes "verrucatus" 30 x 27 mf prv PIN 12 10x94.9 22 Tuberositriletes "verrucatus" 30x27 If prv PIN 12 10x94.9 23 Zlivisporis blanensis 55 x 52 mf prv N 120 18.3x95.4 24 Zlivisporis blanensis 55x52 exine prv N 120 18.3x95.4

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Figure A-5. Illustration of palynomorphs see key to labels in Figure A-l taxa size focus view slide coordenates 1 Araucariaciates "rugulatus" 66x40 If pv N 149 1 1.3 x 92.5 2 Araucariaciates "rugulatus" 66x40 mf pv N 149 11.3x92.5 3 Araucariaciates "rugulatus" 66x40 hf pv N 149 11.3x92.5 4 Araucariaciates "scabratus" 56x43 hf pv N74 14.5 x 104.7 5 Araucariaciates "scabratus" 56x43 mf pv N 74 14.5 x 104.7 6 Ephedripites vanegensis 38 x 17 mf ev NA 59+90 4.9 x 86.7 7 Laevigatasporites "laevigatus" 85x40 mf pv N87 8x81.5 8 Laevigatasporites "laevigatus" 85x40 mf pv N 87 8x81.5 9 Aglaoreidia? "foveolatus" 42x25 hf ev N45 14x 111.2 10 Aglaoreidia? "foveolatus" 42x25 mf ev N45 14x 111.2 11 Aglaoreidia? "foveolatus" 42x25 If ev N45 14x 111.2 1 2 Anacolosidites ariani 65x60 mf pv UR 531+120 14.6 x 114.6 1 3 Anacolosidites ariani 65x60 mf pv UR 531+120 14.6 x 114.6 14 Baculamonocolpites "angustus" 33x28 mf UR 761 7.4 x 97.9 15 Baculamonocolpites "angustus" 33 x28 If UR 761 7.4 x 97.9 16 Baculamonocolpites "bimodalis" 40x28 hf pv PIN 32 7x98 17 Baculamonocolpites "bimodalis" 40x28 mf pv PIN 32 7x98 18 Baculamonocolpites "bimodalis" 40x28 If pv PIN 32 7x98 19 Baculamonocolpites "curubensis" 70x50 mf ev PIN 32+0 9.6 x 90.5 20 Baculamonocolpites 'curubensis" 70x50 mf ev PIN 32+0 9.6 x 90.5 21 Baculamonocolpites "curubensis" 65x50 mf PIN 52+1 10 6.6x97.1 22 Baculamonocolpites "curubensis" 65x50 mf PIN 52+1 10 6.6x97.1 23 Bacumorphomonocolpites tausae 90x60 mf pv UR 502 11.8x97.1 24 Bacumorphomonocolpites tausae 90x60 mf pv UR502 11.8x97.1 25 Bacutriporites "echinatus" 37x37 hf pv PIN 42+100 37 x 37 26 Bacutriporites "echinatus" 37x37 mf pv PIN 42+100 37x37

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Figure A-6. Illustration of palynomorphs see key to labels in Figure A-l size focus view slide coordenates 1 I r? n n i h n cn f* i n 1 1 p c nn tmp lit If we 40x40 mf DV F N21+100 22.5 x 86.8 2 Rnm hn cn c in itPK nnnnp 40x40 mf DV r N21+100 22.5 x 86.8 3 Rnmhn cncinitp? 35 x 38 hf NA 59+90 9.5 x 104.9 fi/itti nncncinitp c hrp\)i c 29 x 27 mf DV F v PIN35+90 5.9 x 80 s nntJihncncinifp c 45 x 39 hmf DV NA46 7.9 x 84.5 6 Bombacacidites "caldensis" 45 x 39 If DV r NA46 7.9 x 84.5 7 Bombacacidites "caldensis" 45 x 39 mf DV F NA46 7.9 x 84.5 b o Bombacacidites "dilcheroi" 35 x 36 hf DV RE67+120 21 x 99.3 9 Bombacacidites "dilcheroi" 35 x 36 mf DV F v RE67+ 1 20 21 x 99.3 10 Bombacacidites "dilcheroi" 35 x 36 |f DV V RE67+120 21 x 99.3 1 1 1 1 Bombacacidites "etayoi" 30 x 33 hf n v Nl 10 7 3 x 1 09 1 12 Bombacacidites "etayoi" 30 x 33 mf DV Nl 10 7.3 x 109.1 13 Bombacacidites "fossureticulatus" 26 x 26 hf DV PIN 28+0 13 x 98.5 14 Bombacacidites "fossureticulatus" 26 x 26 mf DV F v PIN 28+0 13 x 98.5 1 s 1 J Bombacacidites foveoreticulatus 35 x 31 hf n v PIN 8 1 +0 X 11 1 ul TV/ 11 8 x 98 1 1 1 . 0 A 70. 1 16 Bombacacidites foveoreticulatus 35 x 31 mf n v PIN 8 1 +0 I XI 'I O I i\J 1 1 8 x 98 1 1 1 .O A 70. 1 17 Bombacacidites "gentryi" 40 x 39 hf DV F PIN81+0 4.6 x 87 18 Bombacacidites "gentryi" 40x39 mf pv PIN81+0 4.6 x 87 19 Bombacacidites "gentryi" 40x39 mf pv PIN81+0 4.6x87 20 Bombacacidites nacimientoensis 40x40 hf pv PIN 28+0 18.6 x 100.3 21 Bombacacidites nacimientoensis 9x6 mf pv PIN 12+0 10.4 x 103 22 Bombacacidites "protociriloensis" 44x44 mf pv PIN81+0 8.2 x 115.2 23 Bombacacidites "protociriloensis" 44x44 mf pv PIN81+0 8.2 x 115.2 24 Bombacacidites "nissoides" 46x45 hf pv PIN 63+20 21 x 109.9 25 Bombacacidites "nissoides" 46x45 mf pv PIN 63+20 21 x 109.9 26 Bombacacidites "nissoides" 46x45 mf pv PIN 63+20 21 x 109.9

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Figure A-7. Illustration of palynomorphs see key to labels in Figure A-l la A a ci M / L fr\/*nc 1 1 1L U > V 1C W slide cooroenaies I DufilUCitClLlCillcj pruioiuvcurciicuiaiub 18 v 40 JO A HO hf 111 pv M77 1NZ / 70 y 8Q 1 ZU X oy.j / Ac S^ ttl r% SI S* SI S^ 1 SI I t /~) c pruiuiovcurciiLuiaius 18 y 40 mf 1111 P v M77 IyZ / 70 v 8Q 1 ZU X oy.j j DOiriDcicQt tunes proioioveorcucuiaius 10 y 7 1U A / If 11 pv Ml 1 0 IN 1 1U 1 8 1 v OS 16. J X yj n Ac ABM SI S~" SI f t si O proioioveoreiicuiaius 18 y 40 JO A HO hf 111 pv M77 INZ / 8 v 08 O 0 X yo.y J DUtill/ULClLlullcj piUlUlUVCUICllCUlalUS 18 y 40 JO A HO mf 1111 pv M77 1NZ / 8 y 08 Q o x yo.y 6 Bombacacidites proioioveorcucuiaius 18 y 40 Jo X 4U If 1 1 pv M77 1NZ / 8 v OQ O o x yo.y 7 Bombacacidites "psilatus" 10 y 7S JU X Zj mf mi pv I IP 78 1 j.70 UK /ol+ZU 1 A 7 v on Q lo. / x yu.o 8 Bombacacidites "psilatus" 19 Y 10 JZ X JU hf n i pv DC £.H . nfl ix C 0 / + 1 ZU id c v i in 1 O.J X 1 1 u 9 Bombacacidites "psilatus" 10 Y 10 JZ X jU mf 1111 pv DC en i or> Kc 0 / + 1 ZU i e s v i in 1 o.J X 1 1U 10 Bombacacidites "sabanensis" 1Q y 17 jy x j i hf pv PTM Q 1 i M JrllN 01+U 1 A v O 1 A 14 X y 1.4 1 1 Bombacacidites "sabanensis" 1Q y 17 jy X J / mf In] pv PTM 8 1 a-fl rllN ol+U 1 A v O 1 A 14 X y 1.4 12 Bombacacidites "sabanensis" cr\ y 4S JU X 4j mf mi pv PTM S7_i_1 in rllN JZ+1 IU 11 v 1 1 "2 J.J. X 1 1 J 13 Bombacacidites "simplireticulensis" ct v en jZ X jU mf mi pv PTM 7 0 i f\ rllN Zo+U Iz X yj. j 14 Bombacacidites "simplireticulensis" S7 y SO JZ X JO If pv PTM 78-lO r 1IN Zo+U 1 7 y OS S i z x yj.j 15 Bombacacidites soleaformis 42x40 mf pv RE 132 15.5x93 1 6 Bombacacidites soleaformis 45x40 mf pv PIN 81+0 8.1 x93.1 17 Brevitricolpites "macroexinatus" 36x36 hf pv PIN 81+0 19.2 x 83.5 18 Brevitricolpites "macroexinatus" 36x36 mf pv PIN 8 1+0 19.2x83.5 19 Brevitricolpites "macroexinatus" 36x36 if pv PIN 81+0 19.2x83.5 20 Brevitricolpites "microechinatus" 41 x38 hf pv N110 14.1 x 87.5 21 Brevitricolpites "microechinatus" 41 x 38 mf pv N110 14.1 x 87.5 22 Brevitricolpites "microechinatus" 41 x38 mf pv N110 14.1 x 87.5 23 Brevitricolpites "microechinatus" 8x6 colpuspv N110 4.1 x 87

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Figure A-8. Illustration of palynomorphs see key to labels in Figure A-l taxa 1 Brevitricolpites "scabratus" 2 Brevitricolpites "scabratus" 3 Brevitricolpites "scabratus" 4 Clavamonocolpites "macroclavatus" 5 Clavamonocolpites "macroclavatus" 6 Clavamonocolpites "macroclavatus" 7 Clavatricolpites "densoclavatus" 8 Clavatricolpites "densoclavatus" 9 Clavatricolpites "densoclavatus" 10 Clavatricolpites "densoclavatus" 1 1 Colombipollis tropicalis 1 2 Cricotriporites guianensis 13 Cricotriporites guianensis 14 Cricotriporites "macropori" 15 Cricotriporites "macropori" 16 Cricotriporites "macropori" 17 Cricotriporites "macropori" 1 8 Cricotriporites minutipori 19 Cricotriporites "porielongatus" 20 Cricotriporites "porielongatus" 21 Cricotriporites "porielongatus" 22 Crototricolpites cf. annemariae 23 Crototricolpites "protoannemarie" 24 Crototricolpites "protoannemarie" 25 Ctenolophonidites "cruciatus" 26 Ctenolophonidites "cruciatus" 27 Curvimonocolpites inornatus size focus view slide coordenates it v 1A 3j X 34 ni pv M 1 AQ in J4y 20 .4 x 102.8 jj x 34 mi pv m i a a in t4y or\ A i r\o o 20.4 x 102.8 1Z v 14 3j X 34 mf mt pv IN 149 0/"V /I 1 O 20.4 x 102.8 A1 v IS 42 X jj ni pv rllN /1+U 7.5 x 83.8 A1 V ic. 42 X jj mf mt pv dim n i i r\ FIN /l+L) 7.5 x 83.8 42 X jj it pv T5TXT Tl , A FIN /1+0 7.5 x 83.8 3U X 3U mf mt pv PIN 28+0 4.2 x 88.1 1f\ v "2A 3U X 3U mf mt pv PIN 28+0 4.2 x 88.1 32 x 3U mf mt ev FIN 42+100 10.6 x 91 in v in mf mt pv FIN 52+1 10 15 x 1 1 1.6 52 x 45 mt pv XT *7 A N 74 10.2 x 88.8 1f\ v 1A 50 X 24 hi pv r>c in Rh 1 13 1 1.7 x 107.9 30 x 24 mt pv RE 113 1 1.7 x 107.9 45 x 38 r mt pv FIN 75+160 14.9 x 96.9 43 x 36 mt pv RE 67+120 18 x 101.1 35 x 35 mt pv ni\T CC . PIN 55+30 13 x 105.7 50 x 50 mt pv PIN 12 17x91 2 / X 26 mt pv PIN 42+100 7.1 x 82.5 30x28 hf pv PIN 63+20 10.9 x 110 30x28 mf pv PIN 63+20 10.9 x 110 35x39 mf pv PIN 55+30 16.3 x 113 48x46 mf pv UR 531+120 20.6 x 1 1 1 40x40 hf P v N 18 13.3x97.3 40x40 mf pv N 18 13.3x97.3 45x50 mf pv PIN 28+0 18.4 x 111.5 45x50 hf pv PIN 28+0 18.4 x 111.5 29x22 mf pv N4 13.2 x 101

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Figure A-9. Illustration of palynomorphs see key to labels in Figure A-l taxa size focus view slide coorde nates I Cyclusphaera "scabratus" 31 x 23 hf pv N 354+120 5.9 x 89.2 2 Cyclusphaera "scabratus" 31 x 23 mf pv N 354+120 5.9 x 89.2 3 Echimonocolpites "tenuiechinatus" 30 x 26 hf ev N 74 11 x 103 4 Echimonocolpites "tenuiechinatus" 30 x 26 mf cv N 74 11 x 103 5 tchipericolpites brevicolpatus 27 x 26 hf pv N120 16.1 x 111.8 6 Echipericolpites "brevicolpatus" 27 x 26 mf pv N120 16.1 x 111.8 7 tchipericolpites brevicolpatus 27 x 26 If pv N120 16.1 x 111.8 8 Echiperiporites estelae 46 x 35 mf pv PIN 28+0 5.2 x 80.5 9 Echiperiporites estelae 28 x 48 mf P v PIN 28+0 5.2 x 80.5 10 Echiperiporites "scabratus" 90x40 mf pv N21+100 12.1 x 110 11 Echiperiporites scabratus 90 x 40 If pv N 21+100 12.1 x 110 1 z Echiperiporites scabratus 90 x 40 hf pv N21+100 12.1 x 110 13 Echiperiporites scabratus 90x40 mf pv N 21+100 12.1 x 110 14 Echitetracolpites echinatus 40 x 40 hf pv PIN 28+0 18.9 x 105.5 15 Echitetracolpites echinatus 40x40 mf pv PIN 28+0 18.9 x 105.5 16 Echitetracolpites "tenuiexinatus" 45 x 39 hf pv PIN 52+100 5.8 x 90.9 17 Echitetracolpites "tenuiexinatus" 45 x 39 mf pv PIN 52+100 5.8 x 90.9 18 Echitetracolpites "tenuiexinatus" 34x35 mf pv PIN 42+100 18.3x85 19 Echitricolpites "linearis" 60x35 hf ev N110 4.1 x 82.3 20 Echitricolpites "linearis" 60x35 mf ev N110 4.1 x 82.3 21 Echitricolpites "linearis" 50x36 mf ev N120 15 x 109 22 Echitriporites "annulatus" 29x29 hf pv PIN 55+30 7x91.5 23 Echitriporites "annulatus" 45x42 mf pv PIN 47+100 7x91.5 24 Echitriporites "retiechinatus" 37x32 If pv RE 113 7x88.6 25 Echitriporites "spissuexinatus" 33x49 hf pv N18 18.4x94.2 26 Echitriporites "spissuexinatus" 33x49 mf pv N18 18.4x94.2

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Figure A10. Illustration of palynomorphs see key to labels in Figure A1 tax a size focus view slide coordenates 1 Echitriporites trianguliformis var. "orbicularis" 22 x 21 U C hr pv PIN 12 7.3 X 83.5 2 Echitriporites trianguliformis var. "orbicularis" 22 x 21 mf pv PIN 12 7.3 X 83.5 J £*t fill ripurilcS VariaOlllS 4j X 4/ mf pv PIN 47+100 87.8 x 5.7 *+ CtflliriporiieS VariaUlIlS 4j X 4z mf pv PIN 47+100 87.8 x 5.7 j ccfiiiriporiies vdriaDiiis A C v A 1 4j X 42 mf pv PIN 47+100 87.8x5.7 6 Foveodiporites guinanesis 36 X 23 hf pv N4 6.5 x 1 10.8 7 Foveodiporitcs giiitianesis 36 X 23 mf pv N4 6.5 x 110.8 8 Foveotricolpites "costatus" 33 x 30 hf pv PIN 12 4x 100.5 9 Foveotricolpites "costatus" 33 x 30 mf pv PIN 12 4 x 100.5 10 Foveotricolpites "costatus" 33 x 30 If pv PIN 12 4 x 100.5 1 1 Foveotricolpites perforatus 35 x 29 mf pv N149 15.9x88.2 12 Foveotricolpites perforatus 35 x 29 If pv N149 15.9 x 88.2 i j r oveoiricoiporites urevicoipatus 1 L. -. 11 36 x 31 hf pv PIN 12 10 x 87 14 Foveotricolporites "brevicolpatus" 36 x 31 mf pv PIN 12 10x87 15 Foveotricolporites "brevicolpatus" 36x31 If pv PIN 12 10x87 16 Foveotricolporites "fossulatus" 40x36 hf ev PIN 52+1 10 7.9 x 89.9 17 Foveotricolporites "fossulatus" 40x36 mi ev 7.9 x 89.9 18 Foveotricolporites "marginatus" 30x27 If pv PIN 52+110 17.9x82.5 19 Foveotricolporites "marginatus" 30x27 mf pv PIN 52+110 17.9x82.5 20 Foveotricolporites "microreticulatus" 30x25 hf ev N 354+120 14.9x96.5 21 Foveotricolporites "microreticulatus" 30 x 25 mf ev N 354+120 14.9 x 96.5 22 Foveotricolporites "poricostatus" 36x34 hf pv N 174 5.7 x 99 23 Foveotricolporites "poricostatus" 36x34 mf pv N 174 5.7 x 99 24 Foveotricolporites "rugulatus" 45x45 mf pv RE 251+30 18.1 x 88.7 25 Foveotricolporites "rugulatus" 40x 27 hf ev PIN 12 102.2 x 101 26 Foveotriporites hammenii 70x60 mf pv UR812 13x96.5

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Figure A-l 1. Illustration of palynomorphs see key to labels in Figure A1 taxa 1 Foveotriporites "poricostatus" 2 Foveotriporites "poricostatus" 3 Foveotriporites "poricostatus" 4 Foveotriporites "poricostatus" 5 Gemmamonocolpites "ambigemmatus" 6 Gemmamonocolpites "ambigemmatus" 7 Gemmamonocolpites gemmatus 8 Gemmamonocolpites gemmatus 9 Gemmamonocolpites "mammiformis" 10 Gemmamonocolpites "mammiformis" 11 Gemmamonocolpites "megagemmatus" 12 Gemmamonocolpites "megagemmatus" 13 Gemmamonocolpites "megagemmatus" 14 Gemmamonocolpites "perfectus" 15 Gemmamonocolpites "perfectus" 16 Jandufouria "minor" 17 Jandufouria "minor" 18 Jandufouria "minor" 19 Jussitriporites "psilatus" 20 Jussitriporites "psilatus" 21 Jussitriporites "psilatus" 22 Jussitriporites undulatus 23 Ladakhipollenites "gemmatus" 24 Ladakhipollenites "gemmatus" 25 Ladakhipollenites rubini 26 Ladakhipollenites rubini 27 Longapertites microfoveolatus 28 Longapertites microfoveolatus 29 Ladakhipollenites simplex size focus view slide coordenates ju X 41) nt pv PIN 8 1 +0 16.3 x 105.5 JU X 4U nt pv PIN 8 1 +0 16.3 x 105.5 JU X 4L) mt pv PIN 81+0 16.3 x 105.5 1 Q v 1 1 1 0 X I 1 __ c mr pv PIN 8 1 +0 19.1 x 89.7 JJ X zl) nt ev UR 812 21 x 84.4 JJ X zU ml ev T I"T> on UR 812 21 x 84.4 11 V O/l X z4 nr pv N 45 20 x 87.1 11 V 0/1 JJ X z4 Lf nr pv N 45 20 x 87. 1 JZ X Z/ mi pv N 18 11.5 x 94 10 v T7 3Z X Z/ mr pv N 18 11.5x94 4z X 34 u c nr ev T\T\T 1 1 y\ PIN 52+ 1 10 18.8 x 87.1 /lO v 1/1 4z X j4 mr ev ni\i 11/1 PIN 52+1 10 18.8 x 87.1 4z X 34 It ev PIN 52+1 10 18.8x87.1 zir\ „ or 4(J X jj nr ev PIN 52+1 10 1 1 x 86.2 /in viz 41) X j_> nr ev PIN 52+1 10 1 1 x 86.2 i/i v in -54 X 3U nr pv PIN 63+20 4.3 x 84 ia v in J4 X JU mr pv PIN 63+20 4.3 x 84 1/1 v in j4 X JU It pv PIN 63+20 4.3 x 84 1 1 v in j 1 X jU mr pv N 4 16.5 x 100 i i „ in J 1 X JU It pv N 4 16.5 x 100 1 1 x y mt pv N 27 13.3 x 91.6 ^n v
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Figure A12. Illustration of palynomorphs6 see key to labels in Figure A1 taxa size focus view slide coordenates 1 Longapertites "ornatus" 45x32 nt ev DIM CO , 1 in FIN 32+1 10 2.9 x 99.9 2 Longapertites "ornatus" 45x32 mi ev FIN 52+1 10 2.9 x 99.9 3 Longapertites "ornatus" 45x32 if it ev FIN 52+1 10 2.9 x 99.9 4 Longapertites proxapertitoides var. proxapertih 48 x 25 „r mi pv N 265 13.4 x 93.5 5 Longapertites proxapertitoides var. reticuloides 44 x 27 ml pv XT ^£.C N 265 8 x 84.3 6 Luminidites "colombianensis" 4o X 43 nr prv T1TXT . (\ PIN 28+0 1 1.9 x 106.8 7 Luminidites "colombianensis" 40 X 43 mt prv FIN 28+0 1 1.9 x 106.8 8 Luminidites "colombianensis" 4o X 43 if It prv PIN 28+0 1 1.9 x 106.8 9 Margocolporites vanwijhei 4U x 40 hi pv RE 67+120 6.9 x 107 10 Mauritiidites franciscoi var. franciscoi 52 x 37 r mi pv XT ^ 1 1 f\f\ N 21 + 100 12 x 107.5 11 Mauritiidites franciscoi var. franciscoi A v O 4 X z mi pv PIN 12 3.3 x 104 12 Mauritiidites franciscoi var. franciscoi c « o 5x2 mf pv PIN 12 6.8 x 97.9 u iviuLir i Liuiiit s jrancistoi var. jranciscoi 7 v 9 ^ / X Z.J mf pv PIN 55+30 6.6 X 93 14 Mauritiidites franciscoi var. franciscoi 4x 1.2 mf pv PIN 28+0 1 1 . 1 x 89 15 Mauritiidites franciscoi yds. franciscoi 3.6 x 1.3 mf pv UR 761 13.1 X78.8 16 Mauritiidites franciscoi var. minimis 30x26 mf pv N 354+120 7.6 x 80.5 1 7 Mauritiidites franciscoi var. pachyexinatus 60 x 55 mf pv PIN 39+166 20.4 x 99.3 1 8 Momipites africanus 23x29 mf pv N 18 8.9 x 87.1 19 Momipites africanus 23 x 29 mt pv XT 1 O N 18 8.9 x 87.1 20 Momipites "pachyexinatus" 41 x 39 mhf pv PIN 32+0 16.1 x97.6 21 Momipites "pachyexinatus" 41 x 39 mmf pv PIN 32+0 16.1 \97.6 22 Monoporopollenites annulatus 30x21 mf ev PIN 35+90 18.2x82.4 23 Monoporopollenites annulatus 36x30 hf ev N 354+120 10.5 X 83.7 24 Nothofagidites "huertasi" 26x24 hf pv PIN 66+80 10x95 25 Nothofagidites "huertasi" 26 x 24 mf pv PIN 66+80 10x95 26 Nothofagidites "lolongatus" 28x28 hf pv RE 241+40 18x92.7 27 Nothofagidites "lolongatus" 28x28 mf pv RE 241+40 18x92.7 28 Perfotricolpites digitatus 38x32 mf pv PIN 42+100 9.2x96.5

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Figure A13. Illustration of palynomorphs see key to labels in Figure A1 taxa size focus view slide coordenates 1 Periretisyncolpites giganteus HOx 10(mf pv La Paz 7 1 2m 10 x 81.2 2 Periretisyncolpites "inciertus" nn v on I ZU X y\) ni pv N 18 7 x 97.6 3 Periretisyncolpites "inciertus" 1 on v on 1 ZU X y\J mf mi pv "NT 1 O 7 x 97.6 4 Periretisyncolpites "inciertus" ZA v -1A J4 X J4 hf ni pv XT 1 O N 18 7 x 97.6 5 Periretisyncolpites "inciertus" 34 X J4 mf mi pv XT 1 O N 18 '7 x 97.6 6 Perisyncolporites pokornyi JZ X JU mf mi pv RE 241+40 6 x 94.5 1 Propylipollis "pseudocostatus" OA v 07 ZD X Z / Uf ni pv PIN 12 12.6 x 113 8 Propylipollis "pseudocostatus" OA «. OO ZO X z / I* mi pv PIN 12 12.6 x 113 9 Propylipollis "pseudocostatus" ZO X z/ if II pv PIN 12 12.6x 113 1 0 Proxapertites cursus ca v ca jU X 50 ml pv NA 59+90 12.8 x 108.5 1 1 Proxapertites humbertoides yj x y(J ml pv UR 531+120 21 x 81.5 1 2 Proxapertites humbertoides ju X 45 hi pv UR 531+120 21 x 81.5 1 3 Proxapertites magnus Dyl V OA 84 A 81) ml pv RE 67+120 23 x 100 14 Proxapertites magnus 75 v 75 /J X / J ii pv N 87 6.2 x 84.5 1 5 Proxapertites operculatus 42x42 mf pv NA 59+90 4.9 x 84.1 1 ri r rsi Yfi no rti top nrif/ihir iu r i UALiperiiies psuaius 28x26 mf pv PIN 42+100 5.5 x 100.5 1 7 Proxapertites psilatus 27x26 mf pv N 354+120 19.1 x91.5 1 8 Proxapertites verrucatus 30x26 mf pv UR 531+120 14.8 x 102.9 19 Proxapertites verrucatus 27x25 hf pv UR 507 10.5x97.1 20 Psilabrevitricolpites "costatus" 30x30 mf pv N18 9.8 x 104 21 Psilabrevitricolpites "costatus" 30 x 30 mf pv N18 9.8 x 104 22 Psilabrevitricolporites "costatus" 36 x 40 hf pv PIN 42+100 12.3 x 112.5 23 Psilabrevitricolporites "costatus" 36x40 mf pv PIN 42+100 12.3 x 112.5 24 Psilabrevitricolporites "operculatus" 19x 19 hf pv PIN 39+166 16 x 100.5 25 Psilabrevitricolporites "operculatus" 19x 19 mf pv PIN 39+166 16 x 100.5

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Figure A14. Illustration of palynomorphs see key to labels in Figure A1 tax a size focus view slide coordenates 1 Psuabrevitricolporites simphformis 26 x 26 ht pv N 21+100 12 x 107.1 2 rsilabrevitricolporites simphformis 26 x 26 nr pv N 21+100 12 x 107.1 3 Psilamonocolpites grandis 51 x 40 mi ev N4 5.5 x 88.2 4 rsilamonocolpites grandis 51 x40 II ev N4 5.5 x 88.2 5 rsilamonocolpites meatus 33 x 28 mf ev N74 14 x 112.1 6 Psilamonocolpites medius 33 x 28 If It ev N74 14 x 112.1 / Psilaperiporites enigmaticus 22 x 20 ht pv NA-2 16.8x91.5 o n *r • *.. t* • .• ii o rsuaperipontes enigmaticus 22x20 mf pv NA -2 16.8x91.5 9 Psilaperiporites "pachyexinatus" 26 x 26 hi pv PIN 71 15 x 107 10 Psilaperiporites "pachyexinatus" 26 x 26 mf pv PIN 71 15 x 107 1 1 Psilaperiporites "pauciporatus" 32 x 29 hf pv PIN 12 13.5 x 87.2 12 Psilaperiporites "pauciporatus" 32 x 29 mf pv PIN 12 13.5x87.2 13 Psilaperiporites "pauciporatus" 32x29 If pv PIN 12 13.5x87.2 14 Psilastephanocolpites "marginatus" 53x50 mf pv PIN 81+0 15 X 105 15 Psilastephanocolpites "marginatus" 53 x 50 ht' pv PIN 81+0 15 X 105 16 Psilastephanocolpites "marginatus" 14 x 12 mf pv PIN 81+0 15 X 105 17 Psilastephanocolpites "punctum" 26x26 hf pv PIN 42+100 15.5 x 110 18 Psilastephanocolpites punctum 26 x 26 r ml pv PIN 42+100 15.5 x 110 1 y Psilastephanocolpontes brevicolpatus 28 x 25 hf ev PIN 42+100 6.9 x 109.9 20 Psilastephanocolpontes "brevicolpatus" 28x25 mf ev PIN 42+100 6.9 x 109.9 2 1 Psilastephanocolpontes "brevicolpatus" 28x28 mf ev PIN 52+1 10 8 x 90.9 22 Psilastephanocolpontes fissilis 41 x 27 mf ev PIN 52+110 12.4 x 109.5 23 Psilastephanocolpontes fissilis 17x22 mf ev PIN 28+0 11.6x 108.2 24 Psilastephanocolpon tes fissilis 22x20 hf pv PIN 19+60 9.4 x 98.5 25 Psilastephanocolpontes "pachyexinatus" 45x40 hf pv PIN 55+30 13.5x85.1 26 Psilastephanocolpontes "pachyexinatus" 45x40 mf pv PIN 55+30 13.5x85.1 27 Psilastephanocolpontes "pachyexinatus" 53x42 It' ev PIN 28+0 8.1 X 97.6 28 Psilastephanocolpontes "pachyexinatus" 53x42 mf ev PIN 28+0 8.1 X 97.6

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Figure A15. Illustration of palynomorphs see key to labels in Figure A1 taxa size focus view slide coordenates i rsiiusicpfiuriocoiporiies psiiaius 59 y 48 hf ni pv PTM 8 1 j-O 14 v 01 s 1+ X y 1 j z r siiusiepnutiotoiporiies pMiaius JZ A 'to mf I Hi pv PTM 8 1 J.H 14 v Ol < 14 X yl. J j rsiiusiepnunoporiies aunuiaius 49 y 4fl 4Z X mf mi pv UK /OI 1 A 9 v 0< O 10.Z X 80. y 4 P silastephanoporites "annulatus" 49 v 4n 4Z X 4U mf mi pv I TP "7£ 1 UK /Ol 10.2 x 8b. y 5 P silastephanoporites "distinctus" 99 v 9A Z / X ZO fll pv PTM 1 A 1 1 i „ qc 1 1.2 x 85.6 6 Psilastephonoporites "distinctus" 99 v 9A 2 / X 20 mf mi pv 1 1 1 u O C £. 1 1.2 x 85.6 7 P silastephanoporites "scabratus" pv M 1 AC\ IN 14V inc.. im i 10.5 x 101 .2 8 P silastephanoporites "scabratus" 9 1 v 1 1 ml pv N 14V IMC 1A1 ^ 10.5 x 101.2 9 Psilasyncolporites "fastigiatus" 1Q v 1Q ZV X ZO It pv Kb Ml 1 A C 1 1 1 1 19. 5 x 111.1 10 Psilasyncolporites "fastigiatus" on v io zy x zo mf mi pv Kb 1 51 1 A C Ill 1 19.5 x 111.1 11 Psilasyncolporites "psilatus" 1 "2 v 1 1 13 X Ij hi pv rlN 4/+10U 1 O O OA C 12.8 x 89.5 12 Psilasyncolporites "psilatus" 13x13 ml pv FIN 47+100 IM Q OA C 12.8 x 89.5 13 Psilatricolporites "crassicolumellatus" in ~ in 3U X 21) nt ev riTM M . 1 1 A PIN 52+1 10 5.5 x 112 14 Psilatricolporites "crassicolumellatus" in v in jU X 21) mf ml ev KIN jz+1 1U 5.5 x 112 15 Psilatricolporites "crassicolumellatus" in v in Jl) X ZU it ev FIN 52+1 10 5.5 x 112 1 6 P silatricolporites crass us A 1 A 1 43 X 43 mi pv PIN 12 12.3 x 84.5 17 Psilatricolporites maculosus 1Q v 1 J 25 X 21 nt ev DIM TC , 1 d f\ PIN 75+160 20 x 87 18 Psilatricolporites maculosus 1Q „ 1 1 zo X 21 ml ev tat v t —* e , < /• r\ PIN 75+160 20 x 87 19 Psilatricolporites operculatus 18x17 nt pv ni\T TA . 1 z' / PIN 39+166 9.8 x 84.6 20 Psilatricolporites "orbicularis" K ic 2j x zj nt pv RE 143+120 20 x 93.7 21 Psilatricolporites "orbicularis" ic « i< ZJ X ZJ hi pv Rh 143+120 /A /A /A ^1 20 x 93.7 z-z rsiiuiricotporiies orDicuiaxis 1C V 1C zj x zj mi pv Rb 143+120 *A /A |A *A ^ 20 x 93.7 z-j r siiuiriLuiponicS poriCOStuiUS in v oc jU x zj mni pv DIM ^ O . 1 AA rlN 42+100 A ** 7 O T O 9.7 x 87.8 / 'A r^CI 1 /J trim 1 ri/~s »n #z> o **t"*/a«-I nrvr , tafiin* 1 * siiuiriLoipuriics poncosiuius in v ic jU X ZJ mmr pv nixr 4^,1 aa rlN 42+100 9.7 x 87.8 £.j r iiiuiricoiponics singuiaris 1 1 V 1 1 31 X Jl nt pv T1TM A1 . 1 AA PIN 42+ 1 00 /A /A y i /A/A ^ 20.6 x 100.2 £U rjlluiriLOtporitcS StngUlaTlS 11 V 1 1 31x31 mnt pv TAT V T A f\ | /A /A PIN 42+100 >A /A y 1 /A/A ^ 20.6 x 100.2 27 Psilatricolporites "singuiaris" ii 1 1 31x31 mr pv TATVT A 1 /A /A PIN 42+100 20.6 x 100.2 rjiiuiricoiporiies singuiaris 11 V 1 1 31x31 It pv TAT V T A -A 1 /A /A PIN 42+ 1 00 /A /A y -| rt/A 20.6 x 100.2 29 Psilatricolporites "spongiosus" 1 1 io 33 x 28 r ml ev N 149 6.2 x 93 30 PsilatricolnoritPK '\nr\no\r\znz." "n y 98 JJ X Zo mf mi ev M 1 40 A i v ni 0.2 X y3 3 1 Psilatricolporites transversalis 31 x25 mf ev PIN 52+1 10 9.7 x 110.4 32 Psilatricolporites triangularis 25x25 mf pv PIN 81+0 10.9 x 87.6 33 Psilatriporites "tenuiexinatus" 30x24 hf pv UR 531+120 12.3 x 106.2 34 Psilatriporites "tenuiexinatus" 30x24 mf pv UR 531+120 12.3 x 106.2 35 Racemonocolpites facilis 50x33 mf ev UR812 13.9 x 104.4 36 Retibrevitricolpites retibolus 16x 16 hf ev PIN 39+166 8.5 x 111.7 37 Retibrevitricolpites retibolus 16x 16 mf ev PIN 39+166 8.5 x 111.7 38 Retibrevitricolpites "santanderensis" 30x29 mf pv RE 143+120 19.2 x 104 39 Retibrevitricolpites "santanderensis" 22x22 mf pv PIN 39+166 3.2 x 114.5

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Figure A16. Illustration of palynomorphs see key to labels in Figure A1 tax a size focus view slide coordenates 1 nflCPmnnnpnlnitPs: 'VnctQnpmmitnc" i i\i*\*eiii\jiiui,\jipiie$ LUMai£CIinild.lUS OU X 45 ht ev N 354+120 9.9 x 93.5 2 KflCPmotinmtnitP^ 'Vr\cta rr*=*mmat nc " en v ^ o jU X 4o r mi ev N 354+120 9.9 x 93.5 1 l\ flCPYil fill Clf fit r\ltp? rn romn ti j c ** **t*i'Cfiiuriisi*L/l[Jllcj f LILcrrlCllUj JO X ZZ mf ev N 27 8.2 x 85.7 4 r\ (~1 C PYI1 fill rif nl r~\i t £> c rsir-ams-itur ' **ui~ciriufiULUipiic3 ruLcf/luiLlS 53 x 34 mf RE 67+120 16.2x99.4 txctiui cviiriLUipitcS COSlalUS 33 x 32 hf pv PIN 81+0 17.9x80.8 O Rptihfpvitrir/llnitpv "rT^ctatnc" w ivc*ti// cvn i iLUlfsllcj LUMalUS 55 X 51 mf pv PIN 81+0 17.9x80.8 / RptlnrPWltrimlnito c f rinti n tils* fa r> i i\ciiL/f evitf ituipiltfb iriQrigiitcillts 19x18 hr pv UR 812 10.6x92.9 X RptlhrPVltrimlnitPS trinrt mi hiti i r t-» III i vLr 1 CVll I lL>lSlfSllCd if lUflxllltllllb in v io iy X 18 hmf pv UR 812 10.6x92.9 9 J\Ptitlirp\)\tr\m]r\r%rito c "rrron/Jic" ^ j\c tii// c viir iHJipt/f iicj tlallUIb 3D x 30 hf pv PINO 14.9 x 111.5 ixciiuf cviif iLuiporiics tzxanQis 30 x 30 mf pv PINO 14.9 x 111.5 1 1 j\c(tcj evi// iLutponies speciosus 26 x 27 If pv N 354+120 3.9x82.1 i_ „.,„." — lu r\ciiaiporiies fjiQgaaietiensis 32 x 23 mf pv N4 18.6x95 i / i\ciiutpufiicj pUI ICUSlalUS 42 x 22 hf pv N45 3.9 x 90.4 i *j i\ciiuipt/f lies p\Jl lCUSlaiUS 42 x 22 hmf pv N45 3.9 x 90.4 1 ' *\ciiutyuf lies pui lCUSlalUS 42 x 22 mlf pv N45 3.9 x 90.4 20 Rpttmnnnml nitp c '*r\A/ati im" a-v/ i \ z i a i iui us i, t./ipiit.) uvdium 40 x 35 hf e v NA 59+90 6.6 x 83.5 21 Retimonocolpites "ovatum" 40 x 35 mf ev MA ^q_l on 6.6 x 83.5 22 Retimonocolpites regio 40x21 hf ev N4 7.6 x 85.3 23 Retimonocolpites regio 40x21 mf ev N4 7.6 x 85.3 24 Retipollenites "baculatus" 40x26 hf N 18 14x82.7 25 Retipollenites "baculatus" 40x26 mf N 18 14x82.7 26 Retipollenites "magnus" 100x70 hf N 114 12.3 x 110.5 27 Retipollenites "magnus" 100x70 If N 114 12.3 x 110.5 28 Retipollenites "magnus" 27x35 hf N 114 12.3 x 110.5 29 Retistephanocolpites angel i 58x49 mf pv N27 20.3 x 101.2 30 Retistephanocolpites angeli 58x49 mf pv N27 20.3 x 101.2

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Figure A17. Illustration of palynomorphs see key to labels in Figure A-l taxa size focus view slide coordenates 1 Retistephanocolpites "fossulatus" 53 x40 hf pv PIN 35+90 15x94 2 Retistephanocolpites "fossulatus" 53x40 mhf pv PIN 35+90 15x94 3 Retistephanocolpites "fossulatus" 53x40 If pv PIN 35+90 15x94 4 Retistephanocolpites "gradatum" 40x35 mf pv PIN 42+100 20 x 110 5 Retistephanocolpites "gradatum" 40x35 If pv PIN 42+100 20 x 110 6 Retistephanocolpites "inciertus" 30x30 If pv PIN 52+1 10 22.3 x 80.3 7 Retistephanocolpites "inciertus" 30x30 mf pv PIN 52+110 22.3 x 80.3 8 Retistephanocolporites festivus 35x35 mf pv PIN 42+100 19.7x98.2 9 Retistephanocolporites festivus 45x45 mf pv PIN 35+90 7.6 x 111.4 10 Retistephanocolporites "fossulatus" 26x26 hf pv PIN 28+0 7.8 x 97.9 1 1 Retistephanocolporites "fossulatus" 26x26 hmf pv PIN 28+0 7.8x97.9 12 Retistephanocolporites "fossulatus" 26x26 mf pv PIN 28+0 7.8 x 97.9 13 Retistephanocolporites "fossulatus" 26x26 [f pv PIN 28+0 7.8 x 97.9 14 Retistephanoporites angelicus 28x25 hf pv PIN 55+30 11 x 113.5 1 5 Retistephanoporites angelicus 28x25 mf pv PIN 55+30 11 x 113.5 16 Retistephanoporites "crassiexinatus" 37x35 hf pv PIN 28+0 5.2 x 85.6 17 Retistephanoporites "crassiexinatus" 37x35 mf pv PIN 28+0 5.2 x 85.6 18 Retistephanoporites "minutipori" 35 x 35 hf pv PIN 28+0 11.4x98.4 19 Retistephanoporites "minutipori" 35 x 35 mf pv PIN 28+0 11.4x98.4 20 Retistephanoporites "regaloi" 30x30 hf pv La Paz 712m 12.7 x 107.9 21 Retistephanoporites "regaloi" 30 x 30 mf pv La Paz 7 12m 12.7 x 107.9 22 Retisyncolporites angularis 46x42 hmf pv RE 251+30 5.5 x 100 23 Retisyncolporites "complicatus" 30x30 hf pv PIN 81+0 3.1 x 95.1 24 Retisyncolporites "complicatus" 30x30 mf pv PIN 81+0 3.1 x 95.1 25 Retisyncolporites "delicatus" 50x50 hf pv PIN 12 5 x 100.9 26 Retisyncolporites "delicatus" 50x50 mf pv PIN 12 5 x 100 9 27 Retisyncolporites "delicatus" 40x40 mf pv N 354+120 11.6x85.3

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Figure A18. Illustration of palynomorphs see key to labels in Figure A1 taxa size focus view slide coordenates 1 Retitricolpites absolutus 27 x 24 hf ev PIN 55+30 4.8 x 10.4 2 Retitricolpites absolutus 27x24 mf ev PIN 55+30 4.8 x 10.4 3 Retitricolpites antonii 26 x 15 hf pv PIN 32+0 14.2 x 107.9 4 Retitricolpites antonii 26 x 15 mf pv PIN 32+0 14.2 x 107.9 5 Retitricolpites "baculensis" 50x35 hf pv N74+0 13.8x82.1 6 Retitricolpites "baculensis" 50x35 mf pv N74+0 13.8x82.1 7 Retitricolpites "baculensis" 50 x 35 If pv N74+0 13.8x82.1 8 Retitricolpites "baculensis" 24 x 17 hf pv PIN 81+0 18.1 x 111.6 9 Retitricolpites clarensis 35 x 35 hf pv PIN 32+0 12.4x97.6 10 Retitricolpites "costatus" 42x40 mhf pv PIN 71+0 42x40 1 1 Retitricolpites "costatus" 42x40 mf pv PIN 7 1+0 42x40 1 2 Retitricolpites florentinus 40x25 hf ev PIN 81+0 9.1 x 89.1 1 3 Retitricolpites florentinus 40x25 mf ev PIN 81+0 9.1 x 89.1 14 Retitricolpites magnus 55x31 mf ev PIN 32+0 19.4x88.8 1 5 Retitricolpites magnus 55x31 If ev PIN 32+0 19.4 x 88.8 16 Retitricolpites "marginocostatus" 40x38 hf pv PIN 19+60 40x38 17 Retitricolpites "marginocostatus" 40x38 mf pv PIN 19+60 40x38 18 Retitricolpites "peculiaris" 50x45 mf pv NA46 11.3x95.9 19 Retitricolpites "peculiaris" 50 x 45 mf pv NA 46 11.3x95.9 20 Retitricolpites "peculiaris" 21 x 19 retic. pv NA46 11.3x95.9 21 Retitricolpites "peculiaris" 40x23 mf ev NA46 22x91 22 Retitricolpites "peculiaris" 45x35 mf pv NA 46 11.5x96.5 23 Retitricolpites perforatus 32x28 hf pv RE 67+120 14.5 x 109.5 24 Retitricolpites perforatus 32x28 hmf pv RE 67+120 14.5 x 109.5 25 Retitricolpites perforatus 32 x 28 mf pv RE 67+120 14.5 x 109.5

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Figure A19. Illustration of palynomorphs see key to labels in Figure A-l taxa size focus view slide coordenates 1 Retitricolpites "protoclarensis" 33 x 31 hi pv N 120 15 x 91.8 2 Retitricolpites "protoclarensis" 33 x 31 mf pv N 120 15x91.8 3 Ketitricolpites saturum 40 x 40 hf pv N 1 10 7.3 x 88.7 4 Retitricolpites saturum 40 x 40 mf pv N 1 10 7.3 x 88.7 5 Retitricolporites "arctus" 30 x 19 hf ev PIN 42+100 8.3 x 78.5 6 Retitricolporites "arctus" 30 x 19 mf ev PIN 42+100 8.3 x 78.5 7 Retitricolporites cienagensis 31 x 29 mf pv PIN 35+90 21 x 110 8 Retitricolporites "delicatus" 33 x 30 hf pv PIN 52+110 11 x91.5 9 Retitricolporites "delicatus" 33 x 30 mf pv PIN 52+110 11 x91.5 10 Retitricolporites "distinctus" 40 x 28 mf ev N 120 18.2x85.2 1 1 Retitricolporites "distinctus" 40 x 28 If ev N 120 18.2 x 85.2 1 2 Retitricolporites grandis 50 x 50 hf pv RE 67+120 2.9 x 90.3 1 3 Retitricolporites grandis 50 x 50 mf pv RE 67+120 2.9 x 90.3 14 Retitricolporites guianensis 30x22 hf ev PIN 32+0 9.8x91 1 5 Retitricolporites guianensis 30 x 22 mf ev PIN 32+0 9.8x91 16 Retitricolporites hispidus 28 x 18 mf ev PIN 39+166 17.6 x 105 17 Retitricolporites "insolitus" 60x60 hf pv PIN 81+0 18.2x79.5 18 Retitricolporites "insolitus" 60x60 mf pv PIN 81+0 18.2x79.5 1 9 Retitricolporites irregularis 28x25 hf pv N 354+120 7.3 x 103.8 20 Retitricolporites "longicolpis" 40x40 hf pv PIN 55+30 7.3 x 89.5 21 Retitricolporites "longicolpis" 40x40 mf pv PIN 55+30 7.3 x 89.5 22 Retitricolporites "marginatus" 50x45 hf pv PIN 28+0 6x 106.5 23 Retitricolporites "marginatus" 50x45 mf pv PIN 28+0 6 x 106.5 24 Retitricolporites "marginatus" 50x45 If PIN 28+0 6x 106.5

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Figure A-20. Illustration of palynomorphs see key to labels in Figure A-l taxa size focus view slide coordenates 1 Retitricolporites mariposus 28 x 25 hi pv N 265 13.7 x 109.1 2 Retitricolporites mariposus 28 x 25 It pv XT OiCC N 265 13.7 x 109.1 3 Retitricolporites mariposus 28 x 25 mi pv XT ^£.C N 265 1 *5 T 1 AA 1 13.7 x 109.1 4 Retitricolporites medius 22 x 20 mi ev XT 1 C A . 1 ^ r\ N 354+120 7.5 x 109.3 5 Retitricolporites "minutus" 25 x 20 ht ev PIN 39+166 6.9 x 1 10.5 6 Retitricolporites "minutus" 25 x 20 mf ev PIN 39+166 6.9 x 1 10.5 7 Retitricolporites pachynexinatus 30 x 30 hf pv PIN 42+100 15.8 x 98.4 8 Retitricolporites pacnynexinatus 30 x 30 mf pv ni\T a f\ t r\r\ PIN 42+100 15.8 x 98.4 9 Retitricolporites "poricostatus" 25 x 25 hf pv N 354+120 11.6x 107 10 Retitricolporites "poricostatus" 25 x 25 mf pv N 354+120 11.6x 107 1 1 Retitricolporites "poricostatus" 25 x 25 If pv N 354+120 11.6 x 107 1 2 Retitricolporites squarrosus 26 x 23 hf ev PIN 35+90 12.5 x 104.1 1 3 Retitricolporites squarrosus 26 x 23 mf ev PIN 35+90 12.5 x 104.1 14 Retitricolporites "tropicalis" 28 x 25 hf pv N 74 7.2 x 106.5 15 Retitricolporites "tropicalis" 28 x 25 mf pv N 74 7.2 x 106.5 16 Retitricolporites "tropicalis" 24x23 hf ev N74 6.5 x 85 17 Retitricolporites "tropicalis" 24 x 23 mf ev N74 6.5 x 85 18 Retitricolporites vestibulatus 40 x 40 hf pv N 174 6.4 x 83.8 19 Retitricolporites "vestibulatus" 40 x 40 mf pv N 174 6.4 x 83.8 20 Retitricolporites "vestibulatus" 40x40 If pv N 174 6.4 x 83.8 21 Retitriporites "amplireticulatus" 40 x 40 hf ev N 110 6.9 x 97.3 22 Retitriporites "amplireticulatus" 40x40 mf ev N 1 10 6.9 x 97.3 23 Retitriporites "amplireticulatus" 40 x 40 If ev N 1 10 6.9 x 97.3 24 Retitriporites annulatus 38 x 30 hf pv N 27 20 x 96.5 25 Retitriporites "annulatus" 38 x 30 mf pv N 27 20 x 96.5 26 Retitriporites "pachyexinatus" 25x25 hf pv PIN 42+100 4.9x93.1 27 Retitriporites "pachyexinatus" 25x25 mf pv PIN 42+100 4.9x93.1 28 Retitriporites "peculiaris" 40x38 hf pv PIN 35+90 5.6 x 84.5 29 Retitriporites "peculiaris" 40x38 hf pv PIN 35+90 5.6 x 84.5 30 Retitriporites "perforatus" 29x27 mf ev PIN 52+1 10 5 x 87.5 31 Retitriporites "perforatus" 29x27 If ev PIN 52+110 5 x 87.5 32 Retitriporites "poricostatus" 35x32 if pv PIN 71+0 18.1 x82 33 Retitriporites "poricostatus" 35x32 mf pv PIN 71+0 18.1 x 82

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Figure A-21. Illustration of palynomorphs see key to labels in Figure A1 taxa size focus view slide cooruenates 1 Rugotricolporites felix jl A ZJ ni ev PTM 98 .A rliN Z5+U 1 /. / X 51 .J 2 Rugotricolporites felix j i x zj mi ev PTM OOiA rliN Zo+u , 177 v oi c 1 /. / X 51 .J 3 Scabrastephanocolpites "casanaris" 4U X JJ hf ni pv M OAC IN ZOJ OA v 1 AO ZU X 1UZ 4 Scabrastephanocolpites "casanaris" 4U X jj mf mi pv M OA^ IN ZOj OA v 1 AO ZU X 1UZ 5 Scabratricolporites "amplocolpatus" 10 v o^ jZ X zo ni ev T TD CIO UK 61Z lu.j x y 1.5 6 Scabratricolporites "amplocolpatus" 0.0 v 0^ 5L X ZJ mf mi ev T ID 010 UK olz in< v oi c iu.5 x yi.j 7 Scabratricolporites "amplocolpatus" 00 v OA 51 X JU mf mi pv T ID C3 OA UK J j 1 + 1ZU ifl C v OO 0 IU.J X 6Z.5 8 Scabratricolporites "tomassoi" OO v OA LI X ZD Lf nt pv DIM yio , i An rliN 4Z+ 1UU 1 1 n .. 1 AO 1 1.9 x 103 9 Scabratricolporites "tomassoi" OO v OA / / X ZD mf mt pv DIM A O i 1 AA rliN 4Z+1UU 1111.1 AO 1 1 .V x luj 10 Scabratriporites "bellus" JO X J 1 Uf nt pv DC OC 1 i OA Kfc, zji+jU c 1 „ oo o 1 1 Scabratriporites "bellus" OA v 7 1 JO X J 1 mt pv Kt ZjI+jU c 1 „ AO O 5.1 x 98.2 12 Spinizonocolpites "brevibaculatus" OA v OA JO X JO mf mt ev I TD Cll , 1 OA UK JJl+lZU 1 A m, 1 AO C 14 x 108.5 13 Spinizonocolpites "brevibaculatus" AC v AC\ 4J X 4U Uf ni ev T TD CO. 1 i 1 OA UK jj 1+1 ZU 01 C « AO zl.j x y / 14 Spinizonocolpites "brevibaculatus" 45 x40 mf ev UR 531+120 21.5x97 15 Spinizonocolpites "breviechinatus" 65x40 hf pv N 110 14.8 x 110.2 16 Spinizonocolpites "breviechinatus" 65 x40 mf pv N 110 14.8 x 110.2 17 Spinizonocolpites "breviechinatus" 40 x 38 mf ev N74 8.2 x 95 18 Spinizonocolpites "grandis" 75x57 mf pv PIN 12 1 1.4 x 111.2 19 Spinizonocolpites "grandis" 40x36 If pv PIN 12 U.4x 111.2 20 Spinizonocolpites "grandis" 34x42 mf pv PIN 12 1 1.4 x 111.2 21 Spinizonocolpites "pachyexinatus" 80x43 hf pv N 174 13 x 108 22 Spinizonocolpites "pachyexinatus" 80x43 mf pv N 174 13 x 108

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Figure A-22. Illustration of palynomorphs see key to labels in Figure A1 taxa size focus view slide coorde nates 1 Spinizonocolpites "pluribaculatus" 55 x40 hf pv UR 761 17.5x92.3 2 Spinizonocolpites "pluribaculatus" 55x40 mf pv UR 761 17.5x92.3 3 Spirosyncolpites spiralis 50x50 hf PIN 81+0 17.9 x 104.5 4 Spirosyncolpites spiralis 50 x 50 mf PIN 81+0 17.9 x 104.5 5 Snirosxncolnitps spiralis 30 x 19 colpus PIN 32+0 19 x 101.8 6 Striatricolpites catatiimhus 42 x 30 hf ev PIN 66+80 15 6 x 108 5 7 Striatricolpites catatiimbus 42 x 30 mf ev PIN 66+80 15.6 x 108.5 8 Striatricolpites minor 18 x 18 mf e/pv N 120 119x1151 9 Striatricolnitp s "orinociK" 41 x 20 hf ev N 74 5 x 96.6 1 0 Striatricolnitp s "orinnms" 41 x 20 hf ev N 74 5 x 96.6 1 Striatricolnitp s "ten ni striatum" 38 x 31 hf ev RE 143+120 iuj i r w / f i — vy 15 6 x 95 2 1 2 Striatricolnitp s "teniiistriatus" 38 x 31 mf ev RE 143+120 15 6 x 95 2 1 3 Striatricolpites "tenuistriatus" 45 x 30 mf ev UR 812 17.8 x 89.4 14 Striatricolporites "digitatus" 35 x 20 mf ev N 21 + 100 16 X 101 9 i v / \ i v i . y 1 5 Striotricolnoritps "rlicntatim** * — * Ul 1 I It 1 /It i 1 1 1 'i / 1 1ICJ UlC,] LUlU J 35 x 20 hf ev N 2 1 + 1 on 11 —111 \J\J 16 X 101 9 1 ft Strifitricolnoritps "retinilatns** 30 x 22 hf C V N 149 19x91 1 7 StriatricolnoritPK "reticulatus" 30 x 22 mf ev N 149 19 x 91 18 Sxncoloorites lisamap 16 x 16 hf nv N 87 1 1 .4 x 84. 1 19 Syncolporites lisantae 16 x 16 mf DV N 87 1 1 .4 x 84. 1 20 Syncolporites marginatus 20 x 17 If DV RE 113 11 5 x 109 4 21 Syncolporites marginatus 20 x 17 mf RE 113 11 5 x 1 09 4 22 SxncolDorites "vernicatus" 17 x 15 If nv N 174 1 2 2 x 114 1 — , — A 1 11 23 Syncolporites "verrucatus" 17 x 15 hf nv N 174 12.2 x 1 14 24 Ulmoideipites krempii 26 x 26 hf N 149 1 8 6 x 96 9 i o.u a y\j. y 25 VerrusteDhanocolnitps "nipiilntiis" mtmf * W • ii>i # \* LSI * / 1 1 ' L. i 1 ' t t L.J 114 C. UlUvUJ 34 x 33 If n v N 265 26 Verrusteohanonorites "pemmatiK" 29 x 26 hf nv PIN 52+ 1 1 0 X 111 JLTl 1 \J 4 ^ x 104 27 VerrusteDhanonorites "pemmatus" 29 x 26 mf nv PIN 52+1 If) I 111 JLTI 1 \J 4 ^ x 1 04 *T . J A 1 ITT 28 Verrutricolpites "irregularis" 33 x 31 If nv PIN 8 1 +0 I il 1 O I TU 8 8 x 87 ? O.O AO/ — 29 V errutricoloites "irregularis" 33 x 31 mf n v PIN 81+0 8.8 x 87.2 30 Wilsonipites margocolpatus 30x25 mf pv RE 132 6.4 x 102.3 31 Verrutricolporites "reticulatus" 43x40 hf pv PIN 52+110 10.5 x 98 32 Verrutricolporites "reticulatus" 43x40 mf pv PIN 52+110 10.5 x 98 33 Verrutricolporites "reticulatus" 42x44 mf pv PIN 81+0 7.6 x 105.5 34 Zonocostites "minor" 14x 15 mf pv PIN 52+1 10 8.4 x 99.2 35 Zonocostites "minor" 11 x 10 mf ev PIN 52+1 10 6.5 x 97.9 36 Zonocostites "minor" 12x 11 mf ev PIN 52+1 10N( 15.4x97.5

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346

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Figure A-23. Illustration of palynomorphs vv=ventral view, AP=archeopyle, lv=lateral view, hv=hypocystal view, pv=proximal view taxa size focus view slide coordenates 1 Achomosphaera sp. A 55x50 If vv PIN 12 6.4 x 94 2 Achomosphaera sp. A 55x50 mf vv PIN 12 6.4 x 94 3 Cordosphaeridium sp. A 100 x 10(hf vv T1TXT A"1 . 1 f\r\ PIN 47+ 100 20.6 x 95.7 4 Cordosphaeridium sp. A 100 x 10(lf vv PIN 47+ 1 00 20.6 x 95.7 5 Cordosphaeridium sp. A 43x30 mf vv TAT X T A *"7 1 i\f\ PIN 47+100 20.6 x 95.7 6 Cordosphaeridium sp. A 35x32 mf AP PIN 12 4 x 95.2 7 Cordosphaeridium sp. A 80x75 hiIV PIN 12 10.5 x 102.5 8 Coronifera sp. A 50x40 nt" lv N 174 13. 1 x80 9 Coronifera sp. A 50x40 hf Iv N 174 13.1 x 80 10 Glaphyrocysta sp. A 70x60 hf vv PIN 35+90 18.4 x 104.3 1 1 Glaphyrocysta sp. A 70x60 If vv PIN 35+90 18.4 x 104.3 12 Glaphyrocysta sp. A 70x60 mf vv PIN 35+90 18.4 x 104.3 1 3 Homotryblium floripes 90x82 hf hv PIN 28+0 11.3x90.1 14 Homotryblium floripes 90x82 If hv PIN 28+0 11.3x90.1 15 Homotryblium floripes 90x82 mf hv PIN 28+0 11.3x90.1 16 Incertae sedis A 50x50 mf pv PIN 42+100 23 x 95.4 17 Incertae sedis A 50 x 50 mf pv PIN 42+100 23 x 95.4

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348

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Figure A-24. Illustration of palynomorphs see key to labels in Figure A-23 taxa size focus view slide coordenates 1 Hystrichosphaeridium sp. A 70x70 hf hv PIN 28+0 12 x 107 2 Hystrichosphaeridium sp. A 70x70 mf hv PIN 28+0 12 x 107 3 Hystrichosphaeridium sp. A 70x70 If hv PIN 28+0 12 x 107 4 Hystrichosphaeridium sp. A 70x70 hf hv PIN 28+0 12 x 107 5 Hystrichosphaeridium sp. A 70x70 If hv PIN 28+0 12 x 107 6 Lingulodinium cf. sicula 50x40 mf lv PIN 35+90 10.3x92.9 1 Lingulodinium cf. sicula 60x53 mf lv PIN 52+110 15.7 x 103 8 Nematosphaeropsis sp. A 90x80 hf dvv PIN 12 18.6x82 9 Nematosphaeropsis sp. A 90x80 If dvv PIN 12 18.6x82 10 Nematosphaeropsis sp. A 90x80 hf dvv PIN 12 18.6x82 1 1 Polysphaeridium sp. A 68x66 If lv PIN 12 5 x 105.7 1 2 Polysphaeridium sp. A 68x66 mf lv PIN 12 5x 105.7 13 Senegalinium sp. A 60x52 mf vv RE 67+120 6x92.1 14 Senegalinium sp. A 60x52 Itvv RE 67+120 6x92.1

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350

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Figure A-25. Illustration of palynomorphs see key to labels in Figure A-23 taxa size focus view slide coordenates 1 Spiniferites cf. mirabilis 75x60 If vv UR 726 9.8 x 107.3 2 Spiniferites cf. mirabilis 75x60 mf vv UR 726 9.8 x 107.3 3 Spiniferites sp. A 60x56 If dvl PIN 12 17.8x99.2 4 Spiniferites sp. A 60x56 mf dvl PIN 12 17.8x99.2 5 Systematophora? sp. A 55x50 hf dvv PIN 28+0 12.5x83.6 6 Systematophora ? sp. A 55x50 mf dvv PIN 28+0 12.5x83.6

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352

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APPENDIX B LITHOLOGICAL DESCRIPTION OF THE PINALERITA SECTION _ Uthologv Green Gavslone Green Gavstone Environment sub-env. gross I g 11 353

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354 PCS 12 PIN 71 FIND 50PIN 69 PIN 68 PIN 67 PIN 66 PIN 65 40 PIN 64 PIN 63 PIN 62 " PIN 61 PIN 60 " Gma Ctystone 5 I i 11 = 5 1 I I i

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355 Grey silicone Grey clay stone Green clayslone 0 8 1 % £ 5. •s. 5

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356

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357 PIN 31 PIN 30 PINS PEN 28 PIN 27 210 PIN 26 PIN 25 PIN 24 PIN 23 PIN 22 PIN 21 PIN 20 PIN 19 Sihstone. red when wheal ere d h'ghi brown wben fresh Gray mudstooe, piane-parald lamination -vass" i/K'rvifrJnu bioturba&ofi Nlasare, medium Qzsandstone "3 3 I Si If it 3

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358

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359 JO: Grey mud I annua c intervened in sandstone beds Medium-grained Q i ssndslone Medium -grained Sandstone Muddy intraclasts :•:*:•:*:•:-: --53: Massive, medium-grained Qz Sandstone Muddy intratlasts Muddy intraclast Mass re, mediumgrained Qz Sandstone

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360

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361

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362

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363 10.8 m Cojered --B_-_-_green claystooe KB: Gretn sfltstone Giraa sfltstone OTcrbank o?erbank Purple claystone red mottled 1 j j i

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364

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365 Conglomerate with Qz and chert fragments Massive, fairly sorted coarse grained Qz sandstone Massive, very coarsegrained lithic sandstone Pebble grains at trough Green claysione 16.2 m covered 360PurpJe c laystone 9 ml covered flood plain 1.1 — o I? |J il U II

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366

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367

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368

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369 !60250_ Fine grained sandstone Green mudstone E3 ~H Fine grained sandstone Fine grained sandstone Light purple day stone, molded ff_-_-tr_v -.-4--------vFrae lo medium lithic sandstone t9s Overt). 1 B II j 1 3

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370 § 121 p S s B 5 p -V-V--ja.-_-a-_ pi? '-"-"-"V 'A™ ™ " Green mudstonc Green to locally purple day stone with sandy pellets Green mudstone Green cUystone II

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371 2 c P \ 1 Hnc grained sandstone ?n Fine grained sandstone Light grey cbystone with sandy peUets Hnc grained sand9one Dark grey ctaysione

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373 Plane parol Id laminated purple daystone Cody Shale Plane parallel laminated grey mudstone Btoturbaied sandstone Burrows ? infilled by mud Massive, purple dayslone PlaDe-paralld laminated green mudstone Purple mudstone Green mudstone Purple mudstone Green mudstone c 'a m, 1 cr I u 1 § coastal plain (suspendedload channels) A Ij az. II lower coastal plain

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374

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375 Muddy intraclasts Massive, medium -grained Medium to coarsegrained sandstone Muddy intradasts Grey mudsioae 12.6 m covered Fine grained sandstone Coal Medium grained sandstone Hghly biotuibatcd c -K Green claystone Z2 Green sfltstone "3 9 M 3 tarv t "5 3 3 J 1 JZ S* | a JS I stal lakes tl.E 0 0 lit "B § lary cha baybead dd'ta 1 i ii ft a? •« ! Bt 1 0 1 n I • I p 11 5

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377 19 30 18 17 16 Z 15 OIJ.Vl 0 n ?,. a i/i L r < 20 12 11 10 9 8 7 106 .-.-""jr.: mm <=* Q Red sifty mottling Dark green mudstooe Medium-grained sandstone H---0 Coarse grained sandslooe Grey daystone IS Dark grey mudstone IpiP :-:->:-:>-:-:iiL
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378 Key to lihological symbols Sj£ Conglomerate trough cross bedding Medium Quartz-sandstone s planar cross-bedding ^s? ripple marks Fine Quartz-sandstone v>s-\j wavy lamination Siltstone , — . lenticular lamination Mudstone — o flaser lamination. "|j~bioturbation Dark grey claystone c^^^ mottling Green claystone Coal Purple claystone

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APPENDIX C LITHOLOGICAL DESCRIPTION OF THE REGADERA SECTION ,9 m. Lithology Lithk Qzarenite, lenticular lamination •y.\\\ ~\{ Masavc Qzarenite. highly ***" u bioturbated Rne Qzarenite. discontinuous I annua hon Environment sub-en v. gross 1 V 0 s i I S 1 1 j 1 1 0 } c J 0. 3 3 0 I bar poir point bar fluvial plain (mixed-load channels) levee M 3 « 379

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380 250214213212;n 210209m0-1-07.0504030201 200199' I9T 197I9i 195 194 193 192 191 190 in in 187 IK 185 — 184 183 182 181 180 179 178 177 m 175 174 173 172 171 fine Qzarenite, matrix supported, angular clasts While Qzarenite Fine Qzarenite, matrix supported, angular clasts White Qzarenite Light grey cUr/stone Medium Qzarenite. matrix supported, angular clasts 2555555555555555^ :->>#^X->X-:-X\^x|x[S^ 1 Qzarenite. matrix supported. .TTTrr^ a angularclasts red muds tone ||X%i3 angul Qzarenite. matrix supported, 'ar clasts .'.'.v. . A Rne Qzarenite, matrix supported. aigular clasts £v£> Fine Qzarenite light grey muds one White Qiarenite while Qzarenite Quara le pebbles J > H point b S in & Ml 1 i i t ., Ill "a "S s Hi channel plugs k 1 levee | poin

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381

PAGE 393

383

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384 very fine, massive, green tithk sandstone tight grey mudstone very fine massive green lithic sandstone

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385 Key tolithologic symbols EfflB conglomerate coarse sandstone : : • : medium sandstone fine sandstone very fine sandstone Xv: mudstone siltstone SSI clay stone intraclasts 1 1 mottling — • (laser lamination plane lamination ZjL planar cross-bedding VxY/ trough cross-bedding ripples , — discontinuous ' lamination „^ lenticular ~" lamination bioturbation

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APPENDIX D LITHOLOGICAL DESCRIPTION OF THE URIBE SECTION Light grey claystone. purple rootled 20 meters covered Environment s ub-en v. gross \ 3 Polygonal Polygonal Massive, medium Quartz sandstone, siliceous cement, 5%tithics, amalgamated channels 47 meters covered 270 meters of a poorly exposed coarse and medium Quartz sandstone, in general fairly to well calibrated, subrounded, a 2-5% muddy yellow matrix. Some thin conglomeratic intervals. Samples from very thin carbonaceous lenses 270 meters of a poorly exposed coarse and medium Quartz sandstone, in general fairly to well calibrated, subrounded, a 2-5% muddy yellow matrix. Some thin conglomeratic intervals. Samples from very thin carbonaceous lenses. J P olygonal 3, railroad T Polygonal 2 Massive lithic Medium Qtzsandstone (Uthics 5%). yellow muddy matrix. Iron oxides 7 9 "2 } s JC 3 i jO ° I! 11 "3 1 » "4! — 1 — ial plain Moad cham -3 1 £1 J i a SL H "o I I 386

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387

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388

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389

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391

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392

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394

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395

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396 395 394 393 39: 391 390 3«9 3H 3X7 38h 3 385 a £ 384 K < 383 £ 2 380 l 379 3 378 377 376 Light gray medium to fine Fractures? filled with caldte Massive coarse lithic sandstone Coarse lithic sandstone Clast -supported conglomerate. ^^^^ ^^^^^y subrounded, fairly sorted, L^^vW %W.%VJwsV sandy matrix, polymictic, (5 < £Qz hiahne, 5 tuff. 5 greensctusts. 10 arenites, 20 quart ales, 30 black chert, 20 yellow lodotites, 5 conglomerate) Light purple altstnne Z~j£ Purple cbystone. red motted. highly biofuiKitrJ p 0 Th^JT— Red clayaone Key to lithology ^Siitiadaata conglomerate [pflj mottling coarse sandstone |-^-»| flaser lamination medium sandstone | 1 plane-parallel lamination H | fine sandstone \7T\ P' anar cross-bedding | very Fine sandstone l^^j trough cross-bedding 7777 Imudstone | — <\ | ripples silts tone l — 1 discontinuous 1 ""1 lamination claystone lenticular I^^H lamination =3 shale

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398 Bauer, A. M, 1993, African-South American Relaionships: A Perspective from the Reptilia, in P. Goldblatt, ed., Biological Relationships between Africa and South America, New Haven, CT, Yale University Press, p. 244-288. Bayona, G., and C. Jaramillo, 1998, Maastrichtian-Paleocene basin evolution of northwestern South America; the transition from a mature extensional basin to foreland basin: American Association of Petroleum Geologists 1998 annual meeting, analytic compact disc. Berggren, W. A., and M.P. Aubry, 1998, The Paleocene/Eocene Epoch/Series Boundary: Chronostratigraphic Framework and Estimated Geochronology, in M.-P. Aubry, S. Lucas, and W. A. Berggren, eds., Late Paleocene-Early Eocene Climatic and Biotic Events in the Marine and Terrestrial Records, New York, Cambridge University Press, p. 18-36. Berggren, W. A., D. V. Kent, M. Aubry, and J. Hardenbol, 1995a, Introduction, in W. A. Berggren, D. V. Kent, M. P. Aubry, and J. Hardenbol, eds., Geochronology Time Scales and Global Stratigraphic Correlation: SEPM Special Publication, SEPM, p. v-vi. Berggren, W. A., D. V. Kent, C. C. Swisher II, and M. Aubry, 1995b, A revised Cenozoic Geochronology and Chronostratigraphy, in W. A. Berggren, D. V. Kent, M. P. Aubry, and J. Hardenbol, eds., Geochronology Time Scales and Global Stratigraphic Correlation: SEPM Special Publication, SEPM, p. 129-212. Berggren, W. A., and K. G. Miller, 1988, Paleogene tropical planktonic foraminiferal biostratigraphy and magnetobiochronology: Micropaleontology, v. 34, p. 362380. Blondel, T. J. A., G. E. Gorin, and R. Jan du Chene, 1993, Sequence stratigraphy in coastal environments: sedimentology and palynofacies of the Miocene in central Tunisia: Special Publications Int. Ass. Sediment., v. 18, p. 161-179. Bolli, H. M., J.-P. Beckmann, and J. B. Saunders, 1994, Benthic foraminiferal biostratigraphy of the south Caribbean region: London, Cambridge University Press, 408 p. Bolli, H. M., and J. B. Saunders, 1985, Oligocene to Holocene low latitude planktic foraminifera, in H. M. Bolli, J. B. Saunders, and K. Perch-Nielsen, eds., Plankton Stratigraphy, London, Cambridge University Press, p. 155-262. Boltovskoy, D., 1988, The range-through method and first-last appearance data in paleontological surveys: Journal of Paleontology, v. 62, p. 157-159. Boulter, M. C, and A. Riddick, 1986, Classification and analysis of palynodebris from the Paleocene sediments of the Forties Field: Sedimentology, v. 33, p. 871-886. Bralower, T. J., O. J. Thomas, E. Thomas, and J. C. Zachos, 1998, High-resolution records of the Late Paleocene thermal maximum and circum-Caribbean volcanism: Is there a causal link? Reply: Geology, v. 26, p. 671. Bralower, T. J., O. J. Thomas, J. C. Zachos, M. M. Hirschmann, U. Rohl, H. Sigurdsson, E. Thomas, and O. L. Whitney, 1997, High-resolution records of the Late

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BIOGRAPHICAL SKETCH Carlos Alberto Jaramillo was born on May 6, 1969, in Bogota, Colombia. He received a bachelor of science degree in Geology from the Universidad Nacional de Colombia in 1992. Following his graduation, Mr. Jaramillo was employed by Bioestratigrafica and Corporation Geologica Ares as a palynologist. In January of 1994 he went to the University of Missouri-Rolla. where he obtained a master of sciences degree in May 1995. He moved to Gainesville in August of 1995 to pursue a Ph.D. at the University of Florida. 417

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* a \ f\ ^ ! have read thls stud y and that in m y °P inion il conforms to acceptable standards of scholarly presentation and k-felJv adequate, in scope aatkmalityAs a 7 dissertation for the degree of Doctor of Piulifsopb.y. \ \ ( | )avid L. Dilcher, Chairman Graduate Research Professor of Botany t a \ fK ? } haVC read thlS Study and that m m y °P inion »* conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality as a dissertation for the degree of Doctor of Philosophy I A WnAcW ' V~ David A. Hodell Professor of Geology sranrfj S £5 , ad thlS St ^ dy and that in ^ °P inion 11 conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality as a dissertation for the degree of Doctor of Philosophy Douglas S.^Ones Professor of Geology ct a I ce ? if y t^t, 1 have read this study and that in my opinion it conforms to acceotable standards of scholarly presentation and is fully adequate, in scope and quE as dissertation for the degree of Doctor of Philosophy Y ' Walter S. Judd Professor of Botany I certify that I have read this study and that in my opinion it conforms to accenfahle standards of scholarly presentation and is fully adequate in scope and S as a dissertation for the degree of Doctor of Philosophy 7 ^ q ^ Steven Manchester Associate Professor of Botany dissertation for the degree of Doctor of Philosophy . ^ q y ' aS a Neil Professor of Geology

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This dissertation was submitted to the Graduate Faculty of the Department of Geology in the College of Liberal Arts and Sciences and to the Graduate School and was accepted as partial fulfillment of the requirements for the degree of Doctor of Philosophy. August 1999 Dean, Graduate School