Origin, Provenance and Exhumation of Gatuncillo, Tonosi and Cobachon Formations

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Origin, Provenance and Exhumation of Gatuncillo, Tonosi and Cobachon Formations Implications for the Tectonic Evolution of the Isthmus of Panama
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english
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Ramirez, Diego A
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University of Florida
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Gainesville, Fla.
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Degree:
Master's ( M.S.)
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University of Florida
Degree Disciplines:
Geology, Geological Sciences
Committee Chair:
FOSTER,DAVID A
Committee Co-Chair:
MIN,KYOUNGWON
Committee Members:
JAEGER,JOHN M

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Subjects / Keywords:
eocene -- exhumation -- panama -- provenance
Geological Sciences -- Dissertations, Academic -- UF
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Geology thesis, M.S.
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theses   ( marcgt )
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Abstract:
The Eocene Gatuncillo, Tonosi´ and Cobacho´n formations constitute the oldestknown Cenozoic sedimentary successions in Central Panama and the AzueroPeninsula. New detrital zircon U-Pb ages and detrital apatite helium cooling agesobtained in these formations, combined with previous and unpublishedgeochronological and thermochronological studies in igneous and sedimentary rocks,suggest a sequence of four exhumation episodes of the Panamanian VolcaniclasticBasement Complex. These events occurred at (1) 47 - 42 Ma, (2) 32 - 28 Ma, (3) 22 -15 Ma and (4) 9 - 0 Ma; and are related to the tectonic interaction between thePanamanian Arc with the Farallon and South American plates and the GorgonaPlateau. The episodes were associated with emergence of land areas based on thepresence of unroofed and volcanic zircons deposited in the sedimentary formationssince the middle Eocene until the late Miocene. Lu-Hf isotopic data from detrital and intrusive zircons reveal EHf values between +3 and+16, suggesting an island arc origin for the Panamanian Basement Complex.
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In the series University of Florida Digital Collections.
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Includes vita.
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by Diego A Ramirez.
Thesis:
Thesis (M.S.)--University of Florida, 2013.
Local:
Adviser: FOSTER,DAVID A.
Local:
Co-adviser: MIN,KYOUNGWON.

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1 ORIGIN, PROVENANCE AND EXHUMATION OF GATUNCILLO, TONOSI AND COBACHON FORMATIONS: IMPLICATIONS FOR THE TECTONIC EVOLUTION OF THE ISTHMUS OF PANAMA By DIEGO ARMANDO RAMIREZ SARMIENTO A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2013

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2 2013 Diego Armando Ramrez Sarmiento

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3 To Josefa, Julio, San dra and C sar, my lovely family

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4 ACKNOWLEDGMENTS I would like to greatly thank Dr. David Foster for his continuous support, guidance and friendship throughout these years. His great advice helped me to complete one of the most important personal goals I have ach that. I would also like to thank Dr. Kyle Min and Dr. John Jaeger, my other two committee members, who also taught me a lot during all the long discussions and classes we had. Thanks also go to Dr. Bruce MacFa dden and all the PCP PIRE members for their committee, Dr. Mark Brenner also helped me every time I needed advice when my Special tha nks go to Dr. George Kamenov, Dr. Ann Heatherington, Dr. Jen Gifford, Ashley Russell and Matt Droulliard, for all their assistance in the lab, and to Federico Moreno, who kindly helped me to explore Panama and collect all my samples. Dr. Camilo Montes, Dr Carlos Jaramillo, Dr. Agustn Cardona, Dr. David Farris, Dr. Rory McFadden and Dr. Austin Hendy were my advisors and friends during my internship at the Smithsonian Tropical Research Institute; thank you very much to each one of you. Special thanks go t o my good friends: Elliott Arnold, Luz Helena Oviedo, Aldo Rincn, Julia Tejada, Anna Jimnez, Fabiany Herrera, Sean Moran, Dylan Loss, Candler Turner, Chong Ma, James Sutton, Carlos Ortega, Alberto Carmenate, Kevin Werts, Kevin Liebe, Sadie Belica, Caroly n Ball, Patrick Gelato, Grant Weinkham, Alex Hastings, John Ezzel, Qianying Lin, Carly Manz, Derrick Newkirk, Christian Stanciu,

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5 Megan Torpey, Paul Morse, Tania Villase or and Catalina Pimiento, for all the great moments in Gainesville. Finally, I would l ike to thank my family: Josefa, Julio, Sandra, Csar and Rafa. I wouldnt have finished my masters without their love and help. This research was supported by the U.S. National Science Foundation Partnerships in International Research and Education grant 0 966884 (OISE, EAR, DRL), EAR 0824299, and EAR 0418042.

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6 TABLE OF CONTENTS page ACKNOWLEDGMENTS ................................ ................................ ................................ .............. 4 LIST OF TABLES ................................ ................................ ................................ ......................... 8 LIST OF FIGURES ................................ ................................ ................................ ....................... 9 ABSTRACT ................................ ................................ ................................ ................................ 11 CHAPTER 1 INTRODUCTION ................................ ................................ ................................ ................. 12 2 GEOLOGICAL BACKGROUND ................................ ................................ ....................... 15 Volcaniclastic Basement Complexes ................................ ................................ ............... 16 Previous Geochronologic And Thermochronological Studies On The Basement Complex ................................ ................................ ................................ ............................ 17 Cooling Paths Of The Intrusives In Azuero Peninsula, Central Panama And Western Colombia ................................ ................................ ................................ ........... 19 Low Temperature Cooling Events In Central Panama ................................ ................. 20 Eocene Sedimentary Cover ................................ ................................ .............................. 20 Gatuncillo Formation ................................ ................................ ................................ ... 21 Tonosi Formation ................................ ................................ ................................ ......... 22 Cobachn Formation ................................ ................................ ................................ ... 24 3 METHODS ................................ ................................ ................................ ........................... 34 U Pb Geochronology and Hf Isotopic Analysis ................................ .............................. 34 Provenance, Maximum Depositional Age and Source of Strata Using Detrital Zircons ................................ ................................ ................................ ............................... 35 Apatite (U Th)/He Themochronology ................................ ................................ ............... 37 Tectonothermal History Using Detrital Apatites ................................ ............................. 38 4 RESULTS ................................ ................................ ................................ ............................. 40 Detrital Zircon U Pb Geochronology And Detrital Apatite (U Th)/He Thermochronology ................................ ................................ ................................ ........... 40 Gatuncillo Formation ................................ ................................ ................................ ... 40 Modern Sands from Rivers Draining t he San Blas Complex ................................ 42 Tonosi Formation ................................ ................................ ................................ ......... 43 Cobachn Formation ................................ ................................ ................................ ... 43 Zircon U Pb Geochronology and Apatite (U Th)/He Thermochronology of Plutonic Rocks ................................ ................................ ................................ ................. 44 Hf Isotopes in Igneous and Detrital Zircons ................................ ................................ .... 44

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7 5 DISCUSSION ................................ ................................ ................................ ...................... 72 Maximum Depositional Age ................................ ................................ ............................... 72 Provenance ................................ ................................ ................................ .......................... 72 Middle Eocene ................................ ................................ ................................ .............. 73 Late Eocene ................................ ................................ ................................ .................. 73 Late Oligocene ................................ ................................ ................................ ............. 74 Late Miocene ................................ ................................ ................................ ................ 75 Cooling Events Of The Volcanic Arc Basement ................................ ............................. 75 Origin Of Detrital Zircons ................................ ................................ ................................ ... 77 Paleogeographic Implications ................................ ................................ ........................... 78 Exhumation between ~47 42 Ma in Central Panama: ................................ ........ 78 Exhumation between ~32 28 Ma in Azuero Peninsula: ................................ ..... 79 Exhumation between ~22 15 Ma in Central Panama and Azuero Peninsula: ................................ ................................ ................................ .................. 80 Exhumation between ~9 0 M a in Azuero Peninsula: ................................ .......... 81 6 CONCLUSIONS ................................ ................................ ................................ .................. 89 APPENDIX A DESCRIPTION OF THE VOLCANICLASTIC BASEMENT COMPLEXES ................ 91 B ISOTOPIC AGES FROM THE GRANITOIDS IN PANAMA ................................ ......... 97 C IGNEOUS AND DETRITAL U Pb RESULTS ................................ ................................ 99 D IGNEOUS AND DETRITAL Hf RESULTS ................................ ................................ .... 131 LIST OF REFERENCES ................................ ................................ ................................ ......... 138 BIOGRAPHICAL SKETCH ................................ ................................ ................................ ..... 145

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8 LI ST OF TABLES Table page 3 1 Samples, locations and lithology of the samples used in this study (X= analyzed, = Not analyzed, B= Barren) ................................ ................................ ..... 39 4 1 Apatite (U Th)/He results for samples from Cerro Montuoso and Parita Intrusives. ................................ ................................ ................................ ........................ 71 5 1 Maximum depositional ages obtained in this study from the youngest U Pb ages of detrital zircon. YSG = Youngest single grain. ................................ .............. 82

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9 LIST OF FIGURES Figure page 2 1 Location of the study area (Fig. 2 2) and major geologic units (Modified from Buchs et al. (2011)). ................................ ................................ ................................ ....... 26 2 2 Major geological features of the study area.. ................................ ........................... 27 2 3 Cooling paths of the intrusives from Central Panama ................................ ............ 28 2 4 Cooling paths of the intrusives from Azuero Peninsula (CM= Cerro Montuoso, VR= Valle Rico) and Petaquilla (PTQ). ................................ ................... 29 2 5 Age elevation relationship for apatite fission track (AFT) and (U Th)/He thermochro nology (AHe) in: (a) Cerro Azul and (b) Mamon batholith .................. 30 2 6 Outcrop located at abandoned quarry on the new highway to Coln. ................ 31 2 7 Outcrop of the Lower Tonosi Formation at Bucar beach.. ................................ .. 32 2 8 Lithic sandstones and siltstones from the Cobachn Formation at Lajas River. ................................ ................................ ................................ ................................ 33 4 1 Detrital zircon U Pb KDE from sample 300332.. ................................ ..................... 46 4 2 Left: Calcareous litharenite (sample 300332). Right: calcareous volcanic conglomerate. ................................ ................................ ................................ ................. 47 4 3 Detrital AHe KDE from sample 300332. ................................ ................................ ... 48 4 4 Detrital zircon U Pb KDE from sample 300335. ................................ ...................... 49 4 5 Conglomeratic litharenites (sample 300335) interlayered with finely grained, slightly calcareous lithareni tes. ................................ ................................ .................... 50 4 6 Detrital zircon U Pb KDE from sample 300333. ................................ ...................... 51 4 7 Quartz rich arenites from Cemex Quarry (sample 300333) ................................ .. 52 4 8 Detrital zircon U Pb KDE from sample 300339. ................................ ...................... 53 4 9 Detrital zircon U Pb KDE from sample 300340. ................................ ...................... 54 4 10 Fine medium gray calcareous litharenites (sample 300340) underlying a ~5m layer of algal and foraminifera limestones. ................................ ........................ 55 4 11 Detrital AHe KD E from sample 300340 ................................ ................................ .... 56

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10 4 12 Detrital zircon U Pb KDE from sample 300334. ................................ ...................... 57 4 13 Detrital AHe KDE from sample 300334 ................................ ................................ .... 58 4 14 Detrital zircon U Pb KDE from sample 070242. ................................ ...................... 59 4 15 Detrital zircon U Pb KDE from sample 070287. ................................ ...................... 60 4 16 Detrital AHe KDE from sample 070287. ................................ ................................ ... 61 4 17 Detrital zircon U Pb KDE from sample 300349. ................................ ...................... 6 2 4 18 Gray, well sorted, fossiliferous litharenites (sample 300349) ............................... 63 4 19 Detrital AHe KDE from sample 300349. ................................ ................................ ... 64 4 20 Detrital zircon U Pb KDE from sample 300351. ................................ ...................... 65 4 21 Fine medium grained litharenite (sample 300351) interbedded with dark calcareous siltstones ................................ ................................ ................................ ..... 66 4 22 Detrital AHe KDE from sample 300351. ................................ ................................ ... 67 4 23 U Pb mean age of crystallization diagram from sample 060072 (Cerro Montuoso Batholith). ................................ ................................ ................................ ...... 68 4 24 U Pb mean age of crystallization diagram from sample 060065 and 060067. .. 69 4 25 Hf values of detrital zircons plotted versus their U Pb ag es ..................... 70 5 1 Detrital zircon age distribution diagrams (KDEs) of the sandstone samples collected in Gatuncillo Tonos and C obachn Formations.. ................................ ... 83 5 2 Detrital provenance from sand sample 070242 in Rio Diablo (San Blas Range). ................................ ................................ ................................ ............................ 84 5 3 A) Detrital zir con U Pb ages in Rio Mamon and Rio Portogand sand samples. B) Detrital AHe ages obtained in 070287 and 300334. .......................... 85 5 4 AHe ages obtained in sandstones from Gatuncillo (300340), Tonos (30034 9) and Cobachn (300351) formations. ................................ ......................... 86 5 5 Simple depiction of partial to complete resetting of the apatite crystals due to burial in strata from Cobachn, Tonos and Gatuncillo formations. ....................... 87 5 6 Outcrop in Cemex Quarry reveal an unconformity caused by the 22 15 Ma exhumation event ................................ ................................ ................................ ........... 88

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11 Abstract of Thesis Presented to the Graduate School of the U niversity of Florida in Partial Fulfillment of the Requirements for the of Master of Science ORIGIN, PROVENANCE AND EXHUMATION OF GATUNCILLO, TONOSI AND COBACHON FORMATIONS: IMPLICATIONS FOR THE TECTONIC EVOLUTION OF THE ISTHMUS OF PANAMA By Diego Armando Ramrez Sarmiento December 2013 Chair: David Foster Major: Geology The Eocene Gatuncillo, Tonos and Cobachn formations constitute the oldest known Cenozoic sedimentary successions in Central Panama and the Azuero Peninsula. New detrit al zircon U Pb ages and detrital apatite h elium cooling ages obtained in these formations combined with previous and unpublished geochronological and thermochronological studies in igneous and sedimentary rocks, suggest a sequence of four exhumation episo des of the Panamanian Volcaniclastic Basement C omplex. These events occurred at (1) 47 42 Ma, (2) 32 28 Ma, (3) 22 15 Ma and (4) 9 0 Ma ; and are related to the tectonic interaction between the Panamanian Arc with the Farallon and South American pla tes and the Gorgona Plateau. The episodes were associated with emergence of land areas based on the presence of unroofed and volcanic zircons deposited in the sedimentary formations since the middle Eocene until the la te Miocene. Lu Hf isotopic data from detrital and intrusive zircons reveal Hf values between +3 and +16, suggesting a n island arc origin for the Panamanian Basement Complex

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12 CHAPTER 1 INTRODUCTION One of the most important geological events in Cenozoic time was the emergence of the Isthmus o f Panama. The timing of Isthmus uplift that separated the Pacific and the Atlantic oceans, constitutes one of the most outstanding questions i n regional and global tectonics, paleoclimate, paleoceanography and paleontology Closure of the Isthmus gateway has been interpreted as the trigger for the onset of the Northern Hemisphere glaciations, the strengthening of the Gulf Stream current, the Great American Interchange of land mammals and the increase in Caribbean molluscan diversity. Multiple studies bas ed on micropaleontologic, biologic, isotopic and elemental data indicate that the Isthmus of Panama fully separated the Caribbean Sea and the Pacific Ocean by ~7 3.5 Ma (Keigwi n (1978); Keigwin (1982); Duque Caro (1990); Coates et al. (1992); Collins et al. (1996); Kameo and Sato (2000); Beu (2001); Coates et al. (2004); Newkirk and Martin (2009)). A recent study by Montes et al. (2012a), however, proposes that land had emerged in the area of the Isthmus from Late Eocene until at least Late Miocene and im plies that closure took place earlier than 10 Ma Montes et al. (2012a) used new and existing geochronologic and geochemical data from the San Blas and the Azuero Marginal Complex and demonstrated that these igneous suites that span the Isthmus are part of a geochemically homogeneous succession of plateau to supra subduction arc rocks, intruded by a suite of Campanian to Eocene intermediate plutonic rocks (Buchs et al., 2010; Montes et al., 2012a; Montes et al., 2012b). T heir evi dence for lateral continuity or emergence of the arc during the

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13 Eocene times is scarce and based only o n thermochronological data from intrusive bodies located in the vicinity of the Canal Basin. Support for an emerging landmass in Eocene time is reported through studies of pollen f ossils (Graham, 1985). Graham (1985) describe that the local paleoenvironmental setting from the vicinity of the Gatuncillo depositional basin included a series of volcanic islands of moderate to low relief, border ed seaward by shallow limestone depositing coralline communities, fringed by mangrove vegetation of Rhiziphora and Pelliceria But according to Herrera (pers. comm.) it is difficult to determine if the fossil pollen found in th ese outcrops was deposited in situ or transported to the place by marin e currents. By studying the oldest known sedimentary successions deposited in Central Panama and the Azuero Peninsula (Gatuncillo, Cobachn and Tonos Formations) this research is focused on deciphering the early history of this orogen. The thermal informa tion of previously exposed bedrock is retained in the detritus in sedimentary basins adjacent to the orogenic highland. Detrital and igneous zircon U Pb, detrital apatite (U Th)/He ages and Hf isotopic data are used to constrain: (1) the maximum deposition al age of the three stratigraphic successions, (2) the provenance and origin of the detrital sediments, and (3) the cooling episodes that brought the sedimentary rocks and the volcanic basement to the surface. This research addresses fundamental question s related to the paleogeography of southeastern Central America during the early stages of the arc, such as: (1) what was the degree of exhumation of the Isthmus of Panama during the Eocene? and (2) are

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14 the Tertiary formations of Central Panama and Azuero Peninsula related to the emergence and erosion of the volcanic basement? The answer to these questions is not only relevant for geological comprehension in order to understa nd the possible effects of the I sthmus closure on the paleoclimate and paleoceano graphy of the region. For example, the calibration of nucleotide sequence divergence rates in the fossil record provides an important method by which to test many hypotheses of evolution. In the absence of an adequate fossil record, geological events, rath er than the first appearances of sister taxa in the geological record are often used to calibrate molecular clocks (Marko, 2002).

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15 CHAPTER 2 GEOLOGICAL BACKGROUND N umerous models for the origin of the Caribbean Plateau have been proposed in the literature over the past 30 years Meschede and Frisch (1998) and James (2009) support a model which South America. By contrast, Pindell (1990), Mann et al. (2007) and Pindell and Kennan (2001, 2009) propose that the Caribbean formed within the Farallon Plate in a location in the Pacific close to the equator: the Galapagos hotspot. Although the debate still continues, regional paleogeogra phic reconstructions tend to support the latter. The more recent paleomagnetism, geochronologic, thermochronologic and geochemistry studies all favor an origin far from its present position (Acton et al., 2000; Sinton et al., 2000; Lissina, 2005; Montes et al., 2012b). In this context, Buchs et al. (2010) showed that the Central American volcanic arc starts forming on the trailing edge of the Caribbean Plateau (or CLIP, Caribbean Large Igneous Province) at ca. 75 65 Ma. The volcanic arc formed because the rate of spreading in the Proto Caribbean started to drop dramatically and the subduction under Costa Rica and Panama accelerated, initiating significant arc magmatism (Pindell and Kennan, 2001) Part of the Central American volcanic arc with Caribbean Plateau basement is preserved in the Osa and Burica peninsulas (southern Costa Rica), Canajagua Range and Western Chain (Azuero Peninsula, western Panama) and the San Blas Darin Range (central and eastern Panama) (Fig. 2 1). In this section I give a brief description of the rock units that make up the Central American arc and the related cover strata.

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16 Volcaniclastic Basement Complexes Originally interpreted a s solely representing uplifted and exposed edges of the southernmost Caribbean Plateau (Hoernle et al., 2002), many oceanic terranes in Costa Rica and western Panama have recently been reinterpreted as representing a complex association of temporally and g eochemically distinct stages of arc construction atop the CLIP (Buchs et al., 2010). According to Buchs et al. (2009, 2010), the Golfito Complex, Osa Igneous Complex and Azuero Marginal Complex ( Appendix A ; Fig. 2 1) record a series of tectono magmatic epi sodes (Protoarc and Arc) produced by the continuous subduction of the Farallon plate underneath the Late Cretaceous Caribbean plateau. Montes et al. (2012a) also argue that, as well as the units described by Buchs et al. (2009, 2010) in Costa Rica and western Panama, the basement rocks fro m central and eastern Panama (San Blas Range) present a succession of volcanic arc complexes ( Appendix A ). Exposures of these rock s in the San Blas Complex are div ided into three main units based on their immobile trace element concentration. From bottom t o top: 1. Lower member (or Group I): interpreted as an oceanic plateau; 2. Middle member (or Group II): interpreted as a protoarc; and 3. Upper member (or Group III): interpreted as an arc. The geochemical signature of these basaltic successions, which sh ow an evolutionary pattern from oceanic plateau to mature arc, can be traced from Costa Rica to eastern Panama This suggests that all these volcanic complexes comprised part of the same volcanic belt during the Late Cretaceous (Recchi and Metti, 1975; Mon tes et al., 2012b).

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17 Previous Geochronologic And Thermochronological Studies On The Basement Complex Radiometric studies have been conducted on the San Blas Basement Complex since the 1970s. Montes et al. (2012a) summarized the previous data and presente d numerous U Pb zircon analyses of plutonic igneous rocks. These authors show that significant magmatic activity started around 70 Ma and peaked around 50 Ma, which is in agreement with the 75 65 Ma age of initiation of arc volcanism proposed by Buchs et al. (2010). The intrusive rocks of San Blas Range give U Pb zircon ages of 54.1 1.2, 54.7 1.2, 58. 5 1.3 and 58.7 1.4 Ma ( Cerro Azul diorite/gabbro ) and 39.4 0.8 and 49.7 1.0 Ma ( Mamoni tonalite/quartzdiorite ) ( Montes et al. 2012a) ( Appendix B ). Farther east, along the San Blas Range, six geographically spaced granitoids gave crystallization ages of 58.3 1.0, 59.0 1.9, 58.6 1.6, 49.7 1.6, 49.5 1.1 and 49.5 0.9 (Montes, pers. comm ). Two granitoids in western Colombia (Mand Batholith) gave U Pb zircon ages of 42.5 1.3 and 43.8 0.8 Ma (Cardona et al., 2010) Overall these results indicate crystallization of multiple plutons occurred in the Central American arc during Late Paleocene Early Eocene time. Wegner et al. (2011) obtained 40 Ar/ 39 Ar ages from some of the plutonic rocks ( Appendix B ) Amphibole a nalysis from Cerro Azul yield ed 49.38 1.04 Ma and amphiboles from Mamoni yielded 47.18 1.29 Ma. An a m phibole older age of 61.49 2.32 Ma was also reported in a microdiorite from Cerro Azul. At the Chuluganti River, a granodiorite intrusive was dated in 68.52 5.02 Ma (amphibole), and another in Chepo River in 49.90 2.16 Ma (amphibole) (Wegner et al., 2011) Most of these plutons were

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18 emplaced at shallow crustal levels so that the amphibole cooling ages are interpreted as emplacement ages. (U Th)/He in zircon (ZHe), apatite fission track (AFT) and (U Th)/He in apatite (AHe) analyses from Panama and Colo mbia were reported by Montes et al. (2012) Farris et al. (2011) and Villagmez and Spikings (2013) ( Appendix B ). ZHe ages range between ca. 51 and 41 Ma in Cerro Azul; AFT analyses yield cooling ages of ca. 50 44 Ma in Cerro Azul and ca. 45 35 Ma in the Mamoni pluton; and AHe ages range fr om ca. 23 to 6 Ma, with predominant ages at ~12 Ma, in the Cerro Azul; ca. 29 19 Ma in Mamoni and ca. 22 19 Ma in Petaquilla. Younger ages were obtained in the Mand Batholith (western Colombia): ZFT analysis yield 41.6 5.4 and 46.4 5.8 Ma; ZHe yield 3 2.8 0.7 Ma; AFT yield 38.1 5.4 and 37.8 5.2 Ma; and AHe yield 3.9 0.2 Ma (Villagmez and Spikings, 2013). In the Azuero Peninsula, granitoid samples (tonalite and granodiorite) yield U Pb crystallization ages ranging between Late Cretaceous (Maastr ichtian) and Early Eocene (Lutetian). In the Western Chain (Cerro Montuoso), ages reported are: 67.6 1.4 67.6 1.0 and 66.0 1.0 Ma ; in Canajagua Range ( Valle Rico ): 49.2 0.9 Ma; and close to the town of Chitr (Parita): 48.1 1.2 and 41.1 0.7 Ma ( Appendix B ). All these ages are in the same range as the suite of intermediate composition granitic plutonic rocks from the San Blas Complex (Montes et al., 2012b) Lissina (2005) reports 40 Ar/ 39 Ar ages of 50 0.3 Ma (plagioclase) and 49.5 0.2 Ma (Plagioclase) in the Cerro Quema granodiorite (Valle Rico) ; and 50.7 0.1 Ma (plagioclase) on one granite in trusive close to the town of Pedas. A diorite in Son Peninsula gave a biotite cooling age of 50 0.2 Ma.

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19 A recent study by Corral (2013) also give amphibole 40 Ar/ 39 Ar ages from intrusive bodies : 65.7 1.4 Ma for the Cerro Montuoso batholith; 67.9 1.3 66.0 1.1 and 65.6 1.3 Ma for the dacites of the Rio Q uema Formation; 54.8 1.2 Ma for the Valle Ric o batholith and 40.8 1.4 Ma for the Parita batholith. Cardona (pers. comm, unpublished data) reports ZnHe ages of 32.94 0.66 and 32.77 0.62 Ma; and AHe ages of 33.22 1.15 and 29.91 0.83 Ma from the Valle Rico Intrusive. In the Cerro Montuoso pluton ZnHe analyzes yielded cooling ages of 48.79 0.98 and 43.01 0.86 Ma (Cardona, pers. comm.) and AHe ages between ~16 and 10 Ma. The Parita pluto n yields AHe cooling ages between 17 8 Ma (this study) No intrusive igneous rocks with Paleocene Eocene range of ages have been described in Costa Rica Appendix B summarizes the previous geochronology and thermochronology results from Panama from the Azuero Peninsula to Western Colombia. Cooling Paths Of The Intrusives In Azuero Peninsula, Central Panama And Western Colombia Figures 2 3 and 2 4 illustrate the cooling path reconstructions of the intrusives located in Central Panama and western Colombi a, and Azuero Pen insula, respectively ( Appendix B ). According to these results, the Cerro Azul, Mamon and Mand plutons cooled along two episodes: (1) rapid at approximate rates of ~81 o C/My, ~180 o C/My and ~134 o C/My from ~850 o C to ~110 o C, respectively, and (2) at much slower rates of ~1 o C/My, ~1.6 o C/My and ~1 o C/My from ~110 o C to ~75 o C, respectively (Figure 2 3). In contrast, Cerro Montuoso, Valle Rico, Parita and Petaquilla cooled on three episodes ( Figure 2 4) but the ages are not consistent in all the int rusives in order to calculate the rates of cooling at higher temperatures. In Cerro Montuoso, the pluton ic rock with most

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20 consistent results, display cooling events between ~850 o C and ~500 o C at a rate of ~269 o C/My; between ~500 o C and ~230 o C at a rate of ~1 3.6 0 C/My and between ~230 o C and ~75 o C at a rate of 4.4 o C/My. In Valle Rico, the pluton cooled between ~500 o C and ~230 o C at a rate of 12.2 o C/My and between ~230 o C and 75 o C at a rate of 118 o C/My; and Petaquilla cooled at a rate of 31.7 o C/My between ~500 o C an d ~230 o C. Low Temperature Cooling Events In Central Panama The Cerro Azul gabbro and Mamoni quartzdiorite, are the only two plutonic bodies in which previous low temperature thermochronology st udies have been performed in Central Panama (Fig 2 5 ). Accord ing to Montes et al. (2012a), these intrusives, located on the eastern hills of the Canal Basin, experienced two main cooling episodes: 1. At 47 42 Ma: This significant cooling episode is recorded by ZHe and AFT data. According to Montes et al. ( 2012a ) this event brought the Cerro Azul and Mamoni granitoids from temperatures of 200 230 0 C to below 110 10 0 C in less than 10 my. 2. At 12 9 Ma: This event, which was only recorded by AHe data from the Cerro Azul pluton, resulted in cooling below ~75 5 0 C. Du ring this episode, the intrusiv e rocks were exhumed over a ver t i cal interval of about 800 m, through temperatures that correspond to the apatite He partial annealing zone (70 or 2 3 km of the crust, at a rate of up to ~1 km/my. Farris et al. (2011) reports an aditional cooling event that might have ocurred between 27 and 18 Ma in the Mamoni intrusive. In this study most of the samples were collected at similar elevations (~200 m) so exhumation associated with this cooling through the AHe partial re tention zone can not be evaluated Eocene Sedimentary Cover Paleocene and early Eocene sedimentary rocks have not been recognized in the Isthmus of Panama (Woodring, 1957) The oldest known Cenozoic sedimentary rocks

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21 comprise the Darin, Gatuncill o, Tonosi and Cobachn formations (Fig. 2 2). Terry (1956) speculated that these units represent a transgression over a predominantly volcanic basement; however, the areal extent of the succession is not well known The next section gives a brief descripti on of the three forearc sedimentary units that were the object of this study: the Gatuncillo, Tonos and Cobachn formations. Gatuncillo Formation The Gatuncillo Formation consists chiefly of a 150 800 m succession of soft, finely bedded, uniformly fin e and even grained yellowish gray or buff colored mudstones, siltstones (slightly calcareous) ( Figure 2 6 ), quartz sandstones, impure bentonites, interbedded lenses of lignite (a few cm to 1 2 m thick) and coralline and foraminiferal limestone (Thompson, 1944; Woodring, 1957; Graham et al., 1985 ) A t the base of the sequence a conglomerate ~30 to 90 cm thick consists largely of altered volc anic pebbl es and cobbles resting on altered volcanic rocks (Reeves and Ross, 1930; Thompson, 1944; Woodring, 1957). According to Wo odring and Thompson (1949) the F ormation unconformably overlies the San Blas Complex basement The Ro Gatn fault, however, terminate s the exposure of Gatuncillo Formation to the north, and the Azota fault defines portions of its western limit s (Graham, 1985) such that the depositional contact is not exposed. M icropaleontolo gical studies on the Gatuncillo F ormation started in 1891, when Douvill wrote that calcareous algae and heterostegine and orbitoid foraminifera were found in limestone at San Juan in the Upper Chagres valley (Woodring, 1957). Since then, Vaughan (1926) and Coryell and Embich (1937) studied the foraminiferal fauna, Co oke (1948) the echinoids, Cole (1949) the larger foraminifera, Woodring (1957 1980) the mollusks and Budd et al. (1992) the corals. On the basis of the stratigraphic

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22 distribution of these fossils in other Caribbean de posits, the authors conclude that Gat uncillo is middle (?) to late Eocene in age. All the taxa present clearly indicate growth in shallow (intermediate photic zone, 20 70 m), warm (>22 o C), open marine, clear tropical waters. The lack of planktonic foraminifera and the excellent preservat ion of shells are consistent with in situ deposition and minimal transport. Larger foraminifera and corals are characteristic of tropical waters with littl e input of terrigenous material, suggesting deposition near islands and away from large rivers The p resence of H. alabamemsis supports a deeper shelf depositional setting (Tripati and Zachos, 2002) nevertheless, lignites with presence of Rhizophora, Conocarpus, Avicenia, Laguncularia and Pelliceria pollen evidence also nearshore deposition in mangrove swamps (Graham, 1985). Tripati and Zachos (2002) interpret these sediments as ha ving been deposited in reef and shallow foreslope settings, in water depths of 20 70 m. Tonosi Formation The Tonosi Formation is exposed over most of the Azuero Peninsula (Buchs et al., 2011) and it is conformed by a basal trangressive sequence of ~40 to 400 m thick of coarse clastic rocks with minor coal seams interbedded with shallow marine limestones (Lower unit), followed by a ~500 to 800 m thick deepening upward section of mainly turbiditic sediments (Upper unit) (Kolarsky et al., 1995) The base unit of the Tonosi Formation is Late Eocene (Buchs et al., 2011) and the upper unit ranges in age between the Late Oligocene and Miocene (Kolarsky et al., 1995) At Punta Bucar, target of the present study, the Lower uni t crops out as a 560 m thick section of basal conglomerate and minor sandstones; with no limestones present ( Figure 2 7 ). It is assumed to directly overlie basement, although at this locality

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23 the base of the section is not exposed and the lowermost beds ar e assumed to be faulted against basaltic basement (Kolarsky et al., 1995) Conglomerate beds range from massively bedded to thinly bedded and exhibit no thinning or finning upward trends. Thinly bedded conglomerate is more common than massive conglomerate, with beds of sand and gravel commonly 4 to 5 cm thick. Beds defi ne both planar parallel stratification and tabular foresets. In decreasing abundance, conglomerate clasts include basalt, sandstone and shale fragments similar in lithology to Oc Formation, and shell fragments (Kolarsky et al., 1995) Minor sandstone and siltstone beds make up less than 5% of the section. They are comm only 5 to 200 cm thick, poorly sorted, fine to coarse grained, and rarely pebbly. Sedimentary structures in sandstone beds include normal grading and planar cross stratification and through cross stratification (Kolarsky et al., 1995) According to Krawinkel et al. (1999) the modal analysis to determine the provenance and tectonic setting of this rocks support erosion of an island arc system, uplifted accreted seamounts and metamorphic rocks (Buchs et al., 2011). The geochemistry of the clinopyroxenes present in the Lower Tonosi sandstones indicates derivation from evolved basaltic magma types like within plate tholeiites, ocean floor basalts or volcanic arc basalts. Therefore, this scenario suggests that the uplifted Azuero Arc Group and Azuero Accretionary Complex provided most of the detrital component of the Tonos Forma tion (Buchs et al., 2011). Dominance of stratified conglomerate over massive conglomerate and the complete absence of mudstone interbeds suggest deposition of the Lower Tonos Formation by traction currents of sheet flow in a high energy shallow water

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24 envi ronment. The presence of rare fossil rich beds and lenses in conglomerate and sandstone is interpreted as the product of storm reworking and supports a shallow water environment of deposition (Kolarsky et al., 1995) Fossil fruits and seeds reported by Herrera et al. (2012) indicate the possible presence of nearby lowlan d rainforests in the Bcaro area; in agreement with the description of man groove swamp palynomorphs found in the Gatuncillo Formation by Graham (1985). This macro and micro flora would be the first record of vegetation that colonized land in the Isthmus o f Panama. No depositional ages from the Bucaro beach se ction have been obtained before; t wo samples of finer grained material were barren of microfossils (Kolarsky et al., 1995) Cobachn Formation The Cobachn Formation is a >300 m thick, folded and faulted sedimentary succession that unconformably rests on top of the Azuero Accretionary Complex and is separated by an unconformity from the overlying Tonosi Formation (Buchs et al., 2011). The Cobachn Formation includes three facies: (1) Facies 1: interbeds of volcaniclastic calcareous lutite, siltstone and sandstone ( F igure 2 8 ). The beds are typically 3 to 50 cm thick and define parallel layers that extend over several hundreds of meters. It has been interpreted as turbiditic deposits. (2) Facies 2: is composed of 50 cm to ~50 m (?) thick chaotic deposits, which are in terbedded with Facies 1 and 3. The deposits are matrix supported and contain abundant fragments of basalt, shallow marine limestone and soft deformed sediments. It has been interpreted as mass flow deposits. (3) Facies 3: Is composed of sandstones with abu ndant rounded and well rounded pebbles of basalt and shallow marine limestone. The sediments are matrix supported. It has been interpreted as slope, near littoral deposits. On the basis of these observations, the

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25 Cobachn Formation represents a shallowing upward sequence deposited on top of the Azuero Accretionary Complex (Buchs et al., 2011). An Early to Middle Eocene age can be determined from reworked larger benthic foraminifera near the base of the section, whereas a Middle Eocene age, results from the analysis of large benthic foraminifera in the matrix of chaotic deposits (Buchs et al., 2011).

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26 Fig ure 2 1 Location of the study area (Fig. 2 2) and major geologic units (Modified from Buchs et al. (2011))

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27 Figure 2 2 Major geological f eatures of t he study area. Red stars show the location of the samples collected for this study. Numbers represent intrusives previously dated (Ages reported in Appendix B ) Gatuncillo Tonosi and Cobachn Fm. limits were defined in Stewart et al. (1980) and Buchs et al (2011)

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28 Figure 2 3. Cooling paths of the intrusives from Central Panama (CA= Cerro Azul and Mamon) and western Colombia (Mand).

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29 Figure 2 4. Cooling paths of the intrusives from Azuero Peninsula (CM= Cerro Montuoso, VR= Valle Rico) and Petaq uilla (PTQ).

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30 Figure 2 5 Age elevation relationship for apatite fission track (AFT) and (U Th)/He thermochronology (AHe) in : (a) Cerro Azul ( Modified from Montes et al., 2012) and (b) Mamon batholith ( Modified from Montes et al., 2012 and Farris et al., 2011)

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31 Figure 2 6 Outcrop located at abandoned quarry on the new highway to Coln. Gray, slightly calcareous siltstones underlying foraminiferal limestones of the Gatuncillo Formation (Photo taken by author)

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32 Figure 2 7 Outcrop of the Lower To nosi Formation at Bucar beach. Basal conglomeratic sandstones and coarse sandstones in planar parallel stratification (Photo taken by author)

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33 Figure 2 8 Lithic sa ndstones and siltstones from the Cob achn Formation at Lajas River (Photo taken by auth or)

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34 CHAPTER 3 METHODS Zircon and apatite grains were separated from rock (sedimentary and igneous) and sediment (sand) samples using standard crushing, pulverizing, washing, sieving (No. 50 mesh), heavy liquids (tetrabromoethane (TBE) and methylene iodide (MeI)) and paramagnetic procedures. The samples used in this s tudy and location information are given in Table 3 1 and Figure 2 2 U Pb Geochronology and Hf Isotopic Analysis For U Pb and Hf analyses, zircon crystals were handpicked and placed onto double sided tape, mounted in an epoxy plug together with FC 1 standards, and polished to expose the central region of the grain. Cathodoluminescence (CL) imaging was performed using an SEM (Scanning Electron Microscope) with a Gatan miniCL detector to decipher the internal structures of surface of the sectioned grains. Before laser ablation, the epoxy plugs were cleaned in an ultrasonic bath with diluted HNO3 to remove common Pb surface contamination. Analyses were carried out at the Department of Geological Sc iences, University of Florida, using a Nu Plasma (Nu Instruments, UK) Laser Ablation Multi Collector Inductively Coupled Plasma Mass Spectrometer (LA MC ICP MS). The mounted zircon grains were ablated with a New Wave 213 nm ultraviolet laser, using a laser spot size of 20 transport into the mass spectrometer. Before each ablation, a zero measurement was taken for 20s in order to take on line corrections for isobaric interferences, es pecially from 204 Hg, a common product of argon gas. Following this blank period, laser ablation commenced for 30s, keeping a constant ablation pit depth, therefore reducing the

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35 existence of elemental fractionation. Ablations occurred in intervals of 10 zir cons, directly preceded and followed by ablation of two FC 1 standard zircons in U Pb analyses. For Hf analyses the ablation time was 120s per crystal, with analysis of one FC 1 standard each 15 unknowns. Detrital and magmatic zircon U Pb data reduction wa s referenced to standard zircon (FC 1) from the Duluth Gabbro dated at 1099.0 0.7 Ma and 1099.1 0.5 Ma (Black et al., 2003). Single ages were calculated in Microsoft Excel using CALAMARI (in house spreadsheet) and then plotted in Kernel Density Plots u sing Density Plotter (Vermeesch, 2012) and Weighted Mean Average plots and inverse Concordia plots using Isoplot/Ex (Ludwig, 2008). Hf isotopic measurements were made following the procedures summarized by Mueller et al. (2008) on zircons previously anal yzed for U Pb. Depleted mantle values et al. (1998); Chondritic Uniform Reservoir (CHUR) values are after Blichert Toft and Albarede (1997), as recommended by Patchett et al. (2004). Correc tions made for background signal, instrumental mass bias, and isobaric interferences of Lu and Yb isotopes on mass 176 are described by Gerdes and Zeh (2009) (Morag et al., 2011). Provenance Maximum Depositional Age and Source of Strata Using Detrital Z ircons Traditionally, U Pb results are plotted on Probability Density Plots (PDP). In this study, interpretations were determined using Kernel Density Estimations (KDE). According to Vermeesch (2012) the Probability Density Plots lacks of theoretical basis and can produce counterintuitive results when data quantity (number of analyses) and/or quality (precision) is high. These are calculated by summing a number of

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36 Gaussian distributions whose means and standard deviations correspond to the individual ages a nd their respective analytical uncertainties. Kernel Density Estimations on the other hand, also involves summing a set of Gaussian distributions, however does not explicitly take into account the analytical uncertainties. In this manner, the provenance s tudy entailed the determination of U Pb ages of 60 to 117 individual zircon grains from each sample, plotted latter on a KDE. Interpretations derived from detrital zircon age populations were based on the view that only clusters of ages record robust sourc es ages. By comparing the ages of the detrital minerals with the ages of the potential sources, it can be determined the ultimate sources of the sediment (Gehrels et al., 2006). To constrain the earliest possible (maximum) depositional ages of the strata, Dickinson and Gehrels (2009) recommend the use of multiple youngest age measures. According to the authors, using the youngest single grain age measured (YSG) and the youngest graphical age peak (YPP) produces the more conservative and statistically robust results. Both measures were analyzed for each one of the samples, however only the YSG ages were taken in count for the analyses. Finally, by combining Lu Hf isotopic data with single detrital zircons of known age, new insights on the provenance and sourc e of the sandstones can be provided (Kinny and Maas, 2003; Morag et al., 2011). The 176 Hf/ 177 Hf of a rock is commonly expressed in terms of Epsilon units, which compare 176 Hf/ 177 Hf of a rock sample with 176 Hf/ 177 Hf of the bulk silicate earth (CHUR): 0 Hf = ((( 176 Hf/ 177 Hf ) 0 sample / ( 176 Hf/ 177 Hf ) 0 CHUR ) 1) x 10 4

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37 Mantle reservoir contributing to crust formation has been depleted gradually with time relative to the CHUR (Chondritic Uniform Reservoir) in terms of Hf and Nd isotopes (Vervoort and Blichert Hf values in zircon are indicative that the U Pb ages represent the extraction age from juvenile material extracted from the mantle at or shortly before being incorporated into the felsic melts with limited crustal contaminatio n whereas negative values are interpreted under the assumption that the parental magmas of the zircons were produced mainly from crustal materials that were originally extracted from the depleted mantle at some earlie r time with limited mixing of juvenile material (Iizuka et al., 2005). Apatite (U Th)/He Themochronology Igneous and detrital apatite crystals were handpicked from the nonmagnetic fraction of the MEI liquid float/TBE sink concentrate using a high power (180x) stereo zoom microscope under refl ected and transmitted light. Each selected grain was inspected for inclusions and digitally measured in at least two different orientations Sample packets were loaded in a stainless stee l planchette along with similarly packed Durango apatite standards (~31.5 Ma; Farley, 2000) and individually heated using a diode laser at 7 Amp for 3 min followed by a second extraction (He re extraction) to ensure complete degassing. The extracted gas w as spiked with a known amount of 99.99% 3 He, purified with a NP 10 getter, and then analyzed using a quadrupole mass spectrometer (QMS) with a Channeltron electron multiplier. Once 4 He measurements were complete, the degassed sample packets were transferre d to teflon vials, mixed with a shot of spike ( 230 Th 235 U 149 Sm) and dissolved with ~5% nitric acid at ~120 C during 3 hours (Shan et al., 2013).

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38 The isotopic ratios of U, Th and Sm were determined using a Thermo Finnigan Element2 Inductively Coupled Pla sma Mass Spectrometer (ICP MS) at the University of Florida. Alpha ejection was corrected using the method of Farley and others (1996), modified by Farley (2002). The method proposed by Rahl et al. (2003) for detrital zircons was not necessary in this stu dy because crystals did not present any signs of abrasion or rounding. Tectonothermal History Using Detrital Apatites Detrital apatite (U Th)/He thermochronologic studies identify the cooling ages of 6 to 14 grains from each sample, providing the thermal information of previously exposed bedrock that now is retained in the sedimentary basin adjacent to the orogenic highland (Bernet and Spiegel, 2004). Helium is produced within apatite grains during alpha decay from Uranium and Thorium isotopes. However, it is only retained at temperatures cooler than ~70 80 0 C. By measuring the (U Th)/He concentrations within each apatite, an age is determined for when that grain was cooled through the partial retention interval Then, the lag time between the cooling age and the time of formation of the sediment or sedimentary rock is the interval of time when the exhumation and erosion occurred (Bernet and Spiegel, 2004).

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39 Table 3 1 Samples, locations and lithology of the samples used in this study (X= analyzed, = Not analyzed, B= Barren) Sample I.D. Coordinates Location Analysis Lithology U Pb AHe Hf 070242 925'11.26"N 7834'17.34"W Diablo River X X Sand 070287 9 5'41.45"N 7755'50.70"W Portogandi river X X Sand 300332 919'52.55"N 7936'48.50 "W Gatuncillo Fm. Road to Santo Domingo X X Calcareous sandstone 300333 9 8'48.70"N 7932'7.15"W Gatuncillo Fm. Cemex Quarry X Quartz arenite 300334 914'15.95"N 79 4'23.29"W Mamoni River X X X Sand 300335 920'21.01"N 7936'47.63"W Gatuncillo Fm. Road to Santo Domingo X Lithic sandstone 300339 916'33.32"N 7943'28.04"W Gatuncillo Fm. New highway to Coln X X Lithic sandstone 300340 912'15.88"N 7939'19.79"W Gatuncillo Fm. New highway, old quarry X X Lith ic sandstone 300342 720'49.70"N 8021'5.47"W Tonosi Fm. Bucar Beach B Conglomeratic sandstone 300344 720'46.28"N 8021'4.79"W Tonosi Fm. Bucar Beach Lithic siltstone 300345 720'42.65"N 8021'5.58"W Tonosi Fm. Bucar Beach Calcareous siltstone 300346 720'37.14"N 8021'6.48"W Tonosi Fm. Bucar Beach B Calcareous siltstone 300347 720'29.29"N 8021'6.59"W Tonosi Fm. Bucar Beach B Calcareous siltstone 300348 720'20.51"N 8021'12.38"W Tonosi Fm. Bucar Beach B Interbedded siltstones 300349 720'4.52"N 8021'17.17"W Tonosi Fm. Bucar Beach X X Calcareous sandstone 300351 712'49.57"N 8042'0.86"W Cob achn Fm. Mouth of Lajas River X X X Lithic sandstone 300352 712'45.07"N 8042'5.47"W Cob achn Fm. Mouth of Lajas River B Conglomeratic sandstone 300353 721'1.12"N 8021'13.79"W Tonosi Fm. Bucar Beach B Conglomeratic sandstone 060065 759'30.40"N 8031'30.90"W Parita X X X Tonalite 060067 759'33.40"N 8031'54.70"W Parita X X Tona lite 060072 743'9.50"N 8049'2.90"W Cerro Montuoso X X X Diorite / Granodiorite

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40 CHAPTER 4 RESULTS Detrital Zircon U Pb Geochronology And Detrital Apatite (U Th)/He Thermochronology All the analytical results are listed in Appendix C and D Gatunc illo Formation A total of 5 sampl es were analyzed for detrital zircon U Pb and two for detrital (U Th)/He ( AHe ) from the Gatuncillo Formation. Samples 300332 and 300335 were collected on the road that connects the old Panama Coln highway with the town of Santo Domingo (see T able 3 1 for coordinates) The first sample (300332) is a well sorted, fine to very fine grained calcareous litharenite overlain by a clast supported, poorly sorted calcareous conglomerate constituted by algae, coral and foraminifera rounded fragments; basalts and daci tes (Figure 4 2). Sr isotopic and U Pb dating studies on the calcareous boulders yield ages of 28 1 and 29 1.9 respectively (Silva, pers. comm.). The litharenite provided 60 detrital zircons with ages ranging between ca. 27 and 70 Ma. The KDE displays 3 clusters of ages with peaks at ca. 28, 38 and 52 Ma (Figure 4 1). The possible maximum depositional ages are: YPP: 28 Ma or YSG: 27 Ma. These ages are in agreement with the isotopic data obtained from the overlaying co nglomerate. AHe analyses yielded 13 single grain cooling ages betwe en ca. 15 and 37 Ma (Figure 4 3). The maximum cluster of ages is present at ca. 22 Ma, however the results also display other crystals with cooling ages between ca. 15 19 and 26 33 Ma. The second sample (300335) is located stratigraphically higher than 300332. It constitutes a ~50cm package of gray conglomeratic litharenites interlayered with finely grained, slightly calc areous litharenites (Figure 4 5). Twenty eight detrital zircons wer e

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41 collected from this sample, which can be grouped in 2 different populations at ca 23 and 50 60 Ma (Figure 4 4). The maximum depositional ages considered for this strata are 21 Ma (YSG) and 23 Ma (YPP). Sample 300333 was collected from a homogeneous pa ckage of quartzose arenites (Figure 4 7) overlying a ~50m outcrop of limestones exploited by Cemex. The contact between the two packages is not clearly exposed in the field, but is interpreted as erosional. Previous Sr isotope ratio studies in the limesto nes yield ages of 40 1 and 37 1 Ma (Silva, pers. comm.). In the sandstones, a total of 141 detrital zircons were analyzed, distinguishing 3 different populations. Peaks in the KDE occur at c a. 32, 45 and 54 Ma (Figure 4 6). The maximum age of depositio n for this sandstone is YPP: ~ 32 Ma or YSG: ~ 27 Ma, evidencing a stratigraphic gap between the deposition of the limestones and the overlying quartzose arenites. Two samples (300339 and 300340) were collected on the new Panama Colon highway. Only 300340 was utilized for detrital AHe thermochronology. Sample 300339 is a medium coarse grained volcanic litharenite interbedded with ~1m volcanic conglomerate strata. This sandstone yield 68 zircon U Pb ages between ca. 41 62 Ma illustrating two representative clusters at ca. 47 a nd 58 Ma in the KDE (Figure 4 8). The maximum depositional age for this sample is about 41 Ma. (YSG) or 47 Ma. (YPP). The sample 300340 was collected in one old quarry near the Chagres River. In the outcrop, a ~3m homogeneous layer o f fine medium gray calcareous litharenites underlie a ~5m layer of algal and fora minifera limestones (Figure 4 10). In this sandstone, fossil fruits are found just below the contact with the limestones. Strontium

PAGE 42

42 isotopic and U Pb ages on the limestones ha ve yield 48 10 and 46 1.9 Ma respectively. The sample collected con tained 101 U Pb detrital zircons with ages distributed between ~ 36 Ma and 72 Ma. Major population s are found a t ca. 44 and 54 Ma. (Figure 4 9). Possible maximum depositional ages are: Y SG: 36 Ma and YPP: 44 Ma. The sample 300340 also yielded 13 AHe ages between ca. 5 28 Ma. The most prominent peak is found at ca. 18 Ma, but one younger (between ca. 5 10 Ma) and older (between ca. 25 29 Ma) are also displayed on the Kernel density p lot (Figure 4 11). Modern S ands from Rivers Draining the San Blas Complex Three sandbar samples were collected on different rivers draining the San Blas Complex. All samples were located inside the river channel and various km. away before its mouth in order to ascertain that all the eroded crystals came from a source inside the river basin. Sample 300334 was collected in the Mamon River ~5km after the Corpus Christi River mouth and ~14km before its mouth into the Bayano River. Nineteen detrital zirco ns yielded highly consistent ages between ca. 40 50 Ma. forming one singl e peak at ca. 42 Ma (Figure 4 12). Apatite Helium KDE for 300334 displays two prominent clusters of cooling ages at ca. 20 and 28 Ma; and two single grain ages at about 8 and 13 M a (Figure 4 13). The other two sand samples were collected on rivers geographically spaced, draining the Caribbean side of the San Blas Complex. S ample 070242 from Rio Diablo yielded 103 U Pb detrital zircon s with ages between ca. 39 and 70 Ma. The Kernel Density Plot displays 4 clusters of ages at ca.

PAGE 43

43 (1) 39, (2) 50 54, (3) 58 62 and (4) 68 72 Ma, with predominant population s in groups 2 and 3 (Figure 4 14). The third sand sample (070287), collected on the Portogand River, contained 72 detrital zi rcons with ages ranging from ca. 3 8 to 52 Ma. The dispersion of U Pb ages was low, forming one singl e peak at ca. 44 Ma (Figure 4 15), very similar in range to the ages obtained in sample 300334, located in central Panam. Sample 070287 displays 15 coolin g ages between ca. 10 and 41 Ma with c lusters at ca. 14, 19 and 32 Ma in the KDE (Figure 4 16) Tonosi Formation Nine litharenite and conglomeratic litharenite samples were collected on Bucar Beach, Azuero Peninsula. O nly one sample contained sufficient d etrital zircon and apatite for U Pb and He analysis. Sample 300349 is a gray, well sorted, fossiliferous litharenite located on the top of the Bucar section (Figure 4 18). Eighty five detri tal zircons were analyzed for U Pb, displaying clusters of ages a t ca. 38 and 51 Ma. (Figure 4 17). The maximum depositional age for this sample was established i n YSG: 34 Ma or YPP: 38 Ma. Helium analyses on the apatites yielded 10 cooling ages between ca. 1 and 21 Ma. Except for one crystal with an apparent age of abo ut 20 Ma, the rest fall within the r ange ca. 1 and 10 Ma (Figure 4 19). Cobachn Formation Sample 300351 was collected at one beach outcrop close to the mouth of the Lajas River, on we st Azuero Peninsula (Figure 4 21). The sandstone is a fine medium graine d litharenite interbedded with dark calcareous siltstones. According to Buchs et al. (2011) this outcrop represents the Facies 1 of this formation. This sample gives U Pb

PAGE 44

44 detrital zircon ages ranging between ca. 42 and 56 Ma, establishing one single repres entative cluster at 46 Ma (Figur e 4 20). The maximum depositional age for this sample is YSG: 42 Ma or YPP: 46 Ma. AHe analyses of sample 300351 yielded cooling ages between ~15 and 28 Ma Five grains display a maximum peak at ca. 17 Ma and o ne single cry stal form another peak at ca. 28 Ma in the KDE plot (Figure 4 22) Zircon U Pb Geochronology and Apatite (U Th)/He Thermochronology of Plutonic Rocks Two samples from the Parita Batholith (060065, 060067) and one from Cerro Montuoso Batholith (060072), in the Azuero Peninsula, were collected for zircon U Pb and apatite (U Th)/He analyses ( Table 4 1 ) Twenty two zircons were analyzed from the Cerro Montuoso sample (Figure 4 23). T he Weighted Mean 238 U/ 206 Pb age of the zircons is 67.89 0.59 Ma with 95% c onfidence and an MSWD of 16. The individuation spot analyses yielded ages ranging from ca. 65 71 Ma. This mean age is in agreement with previous U Pb ages obtaine d for this intrusive ( Appendix B ), however the MSWD of the single grain ages suggest that th e mean does not reflect a single population of magmatic z ircons. Two samples from the Parita pluton (060065 and 060067) yielded weighted mean a ges of crystallization of 36.40 0.11 and 37.28 0.27 Ma with MSWD of 0.44 and 1.3, respectively (Fig. 4 24). T hese ages have 95% confidence and reflect the crystallization age of this pluton. Hf Isotopes in Igneous and Detrital Zircons The total range of zircon initial Hf values for igneous, sa ndstones and sands is between + 3 and +16.

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45 Initial Hf values for magmatic zircons from samples 060072, 060065 and 060067 Hf values for detrital zircons from sandstone samples 300351 and 300339 ranges from +12 to +3 and +16 to Hf values for detrital zircons from sand samples 300334 and 070242 ra nge from +16 to 0 and +13 to +3 Hf versus U Pb a ges are presented in Figure 4 25.

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46 Figure 4 1. Detrital zircon U Pb KDE (blue line ) from sample 300332. Black line represents the Probability Density Plot (PDP). The h istogram is in gray and data points are below the graphic.

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47 Figure 4 2 Left: Calcareous litharenite (sample 30033 2) Right: calcareous volcanic conglomerate.

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48 Figure 4 3. Detrital AHe KDE from sample 300332.

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49 Figure 4 4. Detrital zircon U Pb KDE from sample 300335.

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50 Figure 4 5 Conglomeratic litharenites (sample 300335) interlayered with finely grained slightly calcareous litharenites (Photo taken by author)

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51 Figure 4 6. Detrital zircon U Pb KDE from sample 300333.

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52 Figure 4 7. Quartz rich arenites from Cemex Quarry (sample 300333) (Photo taken by author)

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53 Figure 4 8. Detrital zircon U Pb KDE from sample 300339.

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54 Figure 4 9. Detrital zircon U Pb KDE from sample 300340.

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55 Figure 4 10 Fine medium gray calcareous litharenites (sample 300340) underlying a ~5m layer of algal and foraminifera limestones (Photo taken by author)

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56 Figu re 4 11 Detrital AHe KDE from sample 300340

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57 Figure 4 12. Detrital zircon U Pb KDE from sample 300334.

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58 Figure 4 13. Detrital AHe KDE from sample 300334

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59 Figu re 4 14. Detrital zircon U Pb KDE from sample 070242.

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60 Figure 4 15. Detrital zi rcon U Pb KDE from sample 070287.

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61 Figure 4 16. Detrital AHe KDE from sample 070287.

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62 Figure 4 17. Detrital zircon U Pb KDE from sample 300349.

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63 Figure 4 18 Gray, well sorted, fossiliferous litharenites (sample 300349) (Photo taken by author)

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64 Figure 4 19. Detrital AHe KDE from sample 300349.

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65 Figure 4 20. Detrital zircon U Pb KDE from sample 300351.

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66 Figure 4 21 Fine medium grained litharenite (sample 300351) interbedded with dark calcareous siltstones (Photo taken by author)

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67 Figure 4 22. Detrital AHe KDE from sample 300351.

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68 Figure 4 23. U Pb mean age of crystallization diagram from sample 060072 (Cerro Montuoso Batholith)

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69 Figure 4 24. U Pb mean age of crysta llization diagram from sample 06 0065 and 060067.

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70 Fig ure 4 25 Initial Hf values of detrital zircons plotted versus their U Pb ages Igneous samples: 060065, 060067 (Parita) and 060 073 (Cerro Montuoso). Sandstone samples: 300339 (Gatuncillo Formation) and 300351 (Cobach n F ormation). Sand samples: 070242 ( Rio Diablo) and 300334 (Rio Mamon).

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71 Table 4 1. Apatite (U Th )/He results for samples from Cerro Montuoso and Parita Intrusives. Sample Name Mass ( g ) (U Th)/He age ( Ma ) U (ppm) ** Th (ppm) ** Sm (ppm) ** 060072_1 9.77E 06 10.4 0.2 15.1 38.5 734.2 06 0072_2 4.89E 06 12.5 0.4 5.4 19.1 377.2 060072_3 6.18E 06 10.4 0.5 1.0 2.4 87.3 060072_4 1.32E 06 12.8 0.3 37.7 85.4 1498.3 060072_5 2.22E 06 16.6 0.4 25.5 106.6 2255.7 060072_6 2.55E 06 16.6 0.4 11.6 37.0 1007.8 060065_1 5.29E 05 8.7 0.5 0.1 0.2 8.6 060065_2 1.01E 05 17.5 0.5 1.9 3.0 11.2 analytical error only ** estimated based on the grain morphology combined with the abundance data

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72 CHAPTER 5 DISCUSSION Maximum Depositional Age On the basis of the correlations of fossil assemblages of forami nifera, echinoids, mollusks and corals in several Caribbean deposits, the age of the Gatuncillo Formation is Middle (?) to Late Eocene, the Tonosi Formation is Late Eocene (base unit), and Late Oligocene Miocene (upper unit) ; and the Cobachn Formation i s Early to Middle Eocene (Woodring, 1957; Vaughan, 1926; Coryell and Embich, 1937; Cooke, 1948; Cole, 1949; Budd, 1992; Kolarsky et al, 1995; Buchs et al., 2011) The results of our detrital zircon analyses are consistent with th ese depositional times (Tab le 5 1). Samples from the Gatuncillo Formation the Upper Tonos Formation, and the Cobachn Formation yield maximum depositional ages of 41 and 36 Ma, 34 Ma, and 42 Ma, respectively. The U Pb zircon data from samples 300332, 300333 and 300335 yield age po pulations much younger than Late Eocene and hence these strata are not part of the Gatuncillo Formation. Provenance We analyzed the U Pb ages of ~550 detrital zircons from seven middle Eocene to late Miocene clastic sedimentary samples collected in Centra l Panama and the Azuero Peninsula R esults are organized in this section according to the biostratigraphic age or maximum depositional age of the sample and then compared with the U Pb ages of the intrusive rocks in Panama for provenance interpretation. O ur primary objectives were to : (1) define the age range of the magmatism in the Panamanian basement arc complex (Central American arc), and (2) constrain the

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73 sediment sources (provenance) of the three oldest known Cenozoic sedimentary rock formations in th e Isthmus of Panama: the Gatuncillo, Tonos and Cobachn. Figure 5 1 is a compilation of all U Pb detrital zircon data obtained in this study. Zircon U Pb age distributions based on these zircons display peak populations from 67 to 21 Ma. Our resul ts conf lict with Montes et al. (2012a) contention that magmatic activity ceased throughout the entire arc between 38 and 28 Ma. T he combined age distributions from this study indicate continuous magmatism since the Late Cretaceous until the Late Miocene in the Pa namanian sector of the Central American magmatic arc. The following sections give further explanation of the results through time. Middle Eocene The samples from the Middle Eocene strata collected in the Cobachn (300351) and Gatuncillo (300339) formation s display very similar detrital zircon age distributions (Figure 5 1) These are consistent with provenance sources in the Valle Rico (Azuero) and Mamon (Centra l Panama) intrusives ( Appendix B ); or other plutons of the same age. The second age cluster in sample 300339 can be correlated to the C erro Azul Batholith ( Appendix B ) in Central Panama. No plutons of about 54 58 Ma have been identified in Azuero. This may indicate that Gatuncillo and Cobachn formations shared a common sediment source during the Lutetian. Late Eocene Sample 300340 ( Late Eocene, Gatunc illo Formation ) displays similar provenance as the middle Eocene sample 300339 of Gatuncillo Formation (Figure 5 1) The detrital zircon distribution of 300340 points to the Mamon, Cerro Azul or a s imilar aged pluton ic rocks as the origin of the sediments. Additional detrital zircon ages of ~50 55 Ma, ~60 65 Ma and ~68 72 Ma point to another, as of yet unidentified, plutonic or volcanic

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74 source, which may be located in the Rio Diablo watershed This is based on t he U Pb age distribution of sand sample 070242 (Figure 5 2 ), which indicates the presence of plutonic rocks in the Rio Diablo drainage consistent in age with the unidentified sources Late Oligocene Detrital zircon age distributions indic ate a significant change in the provenance for the Oligocene strata (Figure 5 1) In Central Panama, samples 300332 and 300333 (Unidentified formations) indicate that the Mamon Batholith ( Appendix B ) is no longer the main source of sediments Major peaks suggest Cerro Azul ( Appendix B ) and the unidentified igneous sources from 070242 (Rio Diablo) as the new provenance. S ample 300333 shows a population of zircons with ages between ~28 38 Ma that does not have an obvious plutonic source. Andesitic volcanic rocks and associated intrusives in the Canal Basin overlap this age range (Rooney et al., 2011) and could have contributed these zircons. In sample 300332, three new clusters not present in the older strata are displayed: one coeval to the Parita intrusiv e ( Appendix B ), another coeval to the Petaquilla intrusive ( Appendix B ) or the Bas Obispo volcanism (Rooney et al., 2011) and one last between ~62 70 Ma coeval to the Chulugant intrusive ( Appendix B ). In Azuero, the sample from Upper Tonos Formation (3 00349) includes contribution s from the Valle Rico intrusive ( Appendix B ) or other similar aged plutons. Two additional components are similar in age to the Parita pluton ( Appendix B ) and the unidentified source of ~50 5 5 Ma in 070242 (Rio Diablo). As wi th the samples from central Panama, there is a shift in provenance from the late Eocene to late Oligocene in Azuero.

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75 Late Miocene Sediment sources in the late Miocene are consis tent with sources from the late Oligocene in Central Panama for zircons older than 26 Ma. Samples 060052, DF11 (Cucaracha Formation), 060054 (Culebra Formation) and 300335 (unidentified formation) s how a new population between ~26 18 Ma coeval to the ash layers found in Las Cascadas (Rincn et al., 2012), Culebra, Cucaracha (Monte s et al., 2012) and Pedro Miguel Formations (Wegner et al., 2011). Local volca nism from the Canal Basin is the likely source for the detrital zircons in the Late Miocene strata. Cooling Events Of The Volcanic Arc Basement Apatite crystals were selected f rom igneous and sedimentary samples (sandstones and sands ) to: (1) detect the low temperature cooling ages r ecorded in the intrusive bodies from the Azuero Peninsula (2) identify the AHe record of exposed intrusives that is now retained in the adjacent ri verbed deposits and (3) estimate the timing of strata exhumation inside the Gatuncillo and Tonos basins. The l ow temperature thermochronology analyses of the intrusive ro cks from the Azuero Peninsula reveal similar results to the slow cooling events prev iously identified in Central Panama and western Colombia between 110 o C and 75 o C since ~45 Ma; however the slow cooling of the intrusives started in Azuero at about 30 Ma (Figures 2 3 and 2 4) I n the Cerro Montuoso B atholith, r ecent dat a reveal ZnHe ages of ~ 48 and 43 Ma (Card ona, p ers. comm.; Appendix B ) and AHe ages between ~16 and 10 (this study) coeval with the 47 42 Ma and the ~ 12 9 cooling event s suggested by Montes et al. ( 2012a) for Central Panama In the Valle Rico intrusive, ZnHe ages of ~32 Ma and AHe ages of ~33 to 29 Ma ( Cardona, pers. comm.; Appendix B ) suggest a rapid cooling episode between 20 0 o C and 75 o C ; and i n t he Parita intrusive AHe cooling ages

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76 between 17 8 Ma (this study) are coeval with the ~ 12 9 cooling episode (Montes et al. 2012a) On the other hand, t he Mamon and Portogand rivers located in the San Blas Range, are separated geographically by ~125 km and the detrital zircons collected from their sands yielded U Pb ages between ~40 and ~50 Ma ; coeval to the Mamon Bathol ith crystallization age (Figure 5 3 A ). D etrital AHe age analyse s in the same sands also indicate that the apatite crystals currently eroded by both rivers cooled in their host rock since ~41 Ma until ~9Ma at temperatures less than 75 o C (Figure 5 3B ) This continuous cooling on both samples is in agreemen t with the slow cooling trend found o n the intrusives from Central Panama and western Colombia Figure 2 3 show s that Cerro Azul, Mamon and Mand cooled rapidly between ~850 o C and ~ 110 o C, but after wards the m started to cool down at slower rates. This scenario suggests that once the plutons reached a temperature below 110 o C, due to the ir emplacement into host rock s at temperature of about 100 o C, its temperature was diminished continuously until its exposure o n the surface In this way, the data from Portogand and Mamon riverbeds evidence the existence of plutons with similar crystallization and cooling history to the Mamon Batholith. The d etrital AHe ages in the sandstones from Gatuncillo (300340), Cobachn (300351) and Tonos (300349) formations suggests two cooling events of the strata : (1) at ~ 20 15 Ma and (2) at ~9 0 Ma (Figure 5 4) These Miocene Pleistocene cooling ages in the Eocene sediments imply tha t these formations were buried to temperatur es between 6 0 o C 75 o C or higher, where the ap atite crystals were completely or partially reset. Samples 300340 and 300351 were buried to temperatures close to 75 o C ( Figure

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77 5 5 P ath 1 ) and then cooled to surface temperatures between ~22 15 Ma. This cool ing event in the sediments is coeval to the slow and continuous cooling identified in the Cerro Azul, Mamon, (Central Panama) Cerro Montuoso and Parita (Azuero Peninsula) intrusives during this period of time (Figure 2 4). The outlier crystals in these tw o sandstones can be explained by the presence of unidentified inclusions in the se apatites the proximity of the apatites to another crystal that provided extra alpha particles to the system or because the crystals were not completely res e t and still conta ined He concentrations during their second cooling Unlike the previous two, s ample 300349 was compl etely reset following the path 2 in Figure 5 5 This strata reached temperatures higher than 75 o C and cooled since ~9 Ma to the present without recording th e ~20 15 cooling episode due to the thicker stratigraphic burial in this p art of the basin (Figure 5 5 ) Origin Of Detrital Zircons Hf isotopes are a geochemical tracer with the potential to provide unique petrogenetic information about the composition o f the magma from which the zircons crystallized (Wu, 2010). Application of this method to detrital zircons can assist in the discrimination between provenances (Flowerdew et al., 2007). In this study, t he Lu Hf isotopic composition of the igneous and det rital zircons previously dated by LA ICP MS were used to : (1) provide new insights into the provenance and sou rce of the sandstones and sands, and (2) estimate the mode of crustal formation of the Panam anian volcaniclastic b asement arc c omplex. The combi ned U Pb and 25) include only positive values for the three intrusive samples (060065, 060067, 060072) collected in Azuero, the sandstones from the Middle Eocene formations (300351, 300339) and the sand in Rio

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78 Mamon (300334). This in dicates a juvenile crustal origin typical of island arcs and similar to the Aleutian and the Mariana arc (Tollstrup and Gill, 2005; Yogodzinski et al., 2010). Interestingly, the U Pb and data for samples 300339 (Gatuncillo) and 300351 (Cobachn) overla p (Figure 4 25) and have the same provenance (Figure 5 1). This suggests that the middle Eocene zircon samples shared a common sediment source and origin. Paleogeographic Implications The detrit al and igneous geochronology, low temperature thermochronolog y and Hf isotopic data presented in this research permit s new interpretations regarding the degree of exhumation and lateral continuity of the basement units of the Isthmus of Panama during the Eocene/Oligocene times. The presence of detrital zircon grain s in the oldest known Cenozoic sedimentary strata in Panama indicates that parts of the Panamanian volcanic lastic ba sement complex were exposed and eroding sediments to the Central Panama and Azuero Basins during the middle Eocene In the following section the magmatic and cooling events summarized from the U Pb and AHe data above are compiled and compared with the timing of tectonic events and cha nges in the tectonic setting. Exhumation between ~ 47 42 Ma in Central Panama : The ZnHe thermochronology in Mamon, Cerro Azul (Central Panama) and Cerro Montuoso (Azuero Peninsula) intrusives indicate that cooled through about 200 o C in Lutetian times ( Appendix B Figure 2 3, 2 4 ). Further cooling through the temperature interval between 200 o C and 110 o C occurre d at much faster rates in the plutonic rocks from Central Panama than in that of the Azuero Peninsula (4.4 o C/My) (Figure 2 3, 2 4). Approximately 5 My after emplacement, the cooling paths indicate that Mamon and

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79 Cerro Azul reached a temperature < 110 o C and afterwards started to experience slow cooling along with the originally colder host rock while Cerro Montuoso and Valle Rico, coeval to the Mamon Batholith, were still located deeper in the crust at temperatures of ~200 o C and ~380 o C, respectively. The d etrital zircons in Gatuncillo (300339) and Cobachn (300351) formations provide evidence for initial unroofing of plutons by about 42 Ma This suggests that both the volcanic basement and the plutons were exposed above sea level during the middle Eocene. W e propose that Cerro Azul and Mamon were the only sedimentary so urces for detrital zircons in the Gatuncillo and Cobachn basins An to +12 in the zircons from these two sa ndstones favors a similar juvenile magmatic source (Figur e 4 25) indicating that the Panamanian volcanic basement complex was continuous along Azuero and Central Panama in agreement with the reconstruction of Montes et al (2012b) According to Whattam et al. (2012), this event may have been caused by the coll ision of the Gorgona Plateau with the Panamanian arc at about 40 Ma. Exhumation between ~32 28 M a in Azuero Peninsula : While the plutons in Central Panama continued cooling slowly and close to the surface, a rapid pulse is recorded in the Valle Rico int rusive between ~32 and 28 Ma This event exposed the batholith to erosion and likely provided sediments in conjunction with Mamon, Cerro Azul, and other unidentified plutons to strata of the Gatuncillo Formation (300340) and Upper Tonos (300349) The det rital zircon distribution of sample 300349 is also consistent with contribution s from the Parita intrusive. This suggests that the ex posure of the Valle Rico and Parita plutons had occurred by this time.

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80 The tectonic cause of this event is unknown; however the uplift might be related to the steepening of the subduction of the Farallon slab (Whattam et al., 2012) or the accretion of an oceanic island Exhumation between ~ 22 15 Ma in Central Panama and Azuero Peninsula : According to Farris et al. (2011), a widespread exhu mation pulse is evidenced in Panama during 27 22 Ma by c ompari ng the ZnHe and AHe ages obtained in the Petaquilla and Mamon intrusives respectively, ( Appendix B ) with the thermochronologic results obtained in the northern Andes However this interpretation is incorrect because these data actually demonstrate that the Petaquilla pluton was at approximately 200 o C during this time and the cooling paths of the intrusives presented in this study (Figure 2 3, 2 4) indicate that Mamon was coo ling slowly since the middle Eocene O ur AHe ages from Gatuncillo (300340) and Cobachn (300351) formations, however, indicate that the Eocene strata w ere exhumed betwe en ~22 15 Ma (Figure 5 4) This is also consistent with the stratigraphic relationship s in the Cemex Quarry (Figure 4 6, 4 7) which indicate that the Eocene limestones from Gatuncillo Formation were uplifted to erosion after ~40 Ma, creating an unconformity until the deposition of the continental derived quartzose sandstones from sample 300 333 (Figure 5 6) On the other hand, t he detrital zircon distribution from sample 300332 (Ga tuncillo Formation) (Figure 5 1) includ es grains with ages of ~28 Ma. The most likely source for these zircons is the felsic volcanism in the Bas Obispo Formation This source for detritus is consistent with the hypothesis of Farris et al. (2011) who suggest that the opening of the Canal Basin occurred at about 28 Ma as a result of the large scale oroclinal flexure of t he Panam an ian arc.

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81 Exhumation between ~9 0 Ma in Azuero Peninsula : AHe cooling ages from t he Tonos Formation between ~9 and 0 Ma (300349) (Figure 5 4) indicate that uplift and exhumation continued during Plio P l e i stocene times. This exhumation event is likely associated with the NE directed shorte ning and deformation of the current fold thru st belt by the subsequent onset of the Cocos Ridge subduction (Morell et al., 2012). This latest phase of uplift and exhumation could also have been associated with the end of circulation between the Pacific and Atlantic oceans.

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82 Table 5 1. Maximum depositional ages obtained in this study from the youngest U Pb ages of detrital zircon. YSG = Youngest single grain. Sample Formation Max. Depositional Age (YSG) Ma. 300351 Cobachn 42 300339 Gatuncillo 41 300340 Gatuncillo 36 300349 Upper Tonos 34 300332 Gatuncillo (?) 27 300333 Gatuncillo (?) 27 300335 Gatuncillo (?) 21

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83 Figure 5 1. Detrital zircon age distribution diagrams (KDEs) of the sandstone samples collected in Gatuncillo (300339 and 300340), Ton os (300349) and Cobachn (300351) Formations. Samples: 300332, 300333 and 300335 are from an unidentified formation. Samples 060052 (SI 827, Cucaracha Fm.) and 060054 (SI 829, Culebra Fm.) are from Montes et al. (2012). David Foster provided sample DF11 f rom Cucaracha Fm. Color blocks represent the range of ages of igneous intrusive bodies in Central Panama and Azuero Peninsula (Coordinates, location and refere nces in Figure 2 2, Appendix B and Table 3 1). MDA: Maximum depositional age.

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84 Figure 5 2. Detrital provenance from sand sample 070242 in Rio Diablo (San Blas Range).

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85 Figure 5 3. A) Detrital zircon U Pb ages in Rio Mamon (300334) and Rio Portogand (070287) sand samples. Both samples are coeval to Mamon Batholith. B) Detrital AHe ag es obta ined in 070287 and 300334

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86 Figure 5 4. AHe ages obtained in sandstones from Gatuncillo (300340), Tonos (300349) and Cobachn (300351) formations

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87 Figure 5 5. Simple depiction of partial to complete r eset ting of the apatite crystals due to burial in st rata from Cobachn, Tonos and Gatuncillo formations.

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88 Figure 5 6 Outcrop in Cemex Quarry reveal an unconformity caused by the 22 15 Ma exhumation event (Photo taken by author)

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89 CHAPTER 6 CONCLUSIONS The m aximum depositional ages defined by U Pb in d etrital zircons have proven to be useful for correlating Eocene strata and identifying units incorrectly mapped adjacent to the Panama Canal Basin by previous studies. The presence of zircon populations <30 Ma in samples from the Santo Domingo road and the Cemex Quarry suggest that these strata are not part of Gatuncillo Formation. The detrital U Pb results evidence a Late Oligocene or younger depositional age, and hence indicate the occurrence of another formation not yet identified in the area that could be correlative to the Canal Basin sequences Montes et al. (2012) suggest a gap in the magmatism during ~38 28 Ma. Our sandstone zircon distributions evidence the occurrence of continuous magmatism and plutonism in Central Panama since the Late Cretaceou s until the Late Miocene. Detrital U Pb and Hf results from the middle Eocene samples (300339 and 300351) suggest that Gatuncillo and Cobachn formations shared a common magmatic arc source during the Lutetian. AHe ages in Valle Rico, the most probable s ource for Cobachn due to its crystallization age and proximity, show that it cooled until ~32 Ma, discarding the possible unroofing of the pluton during this period of time. In this way, the Mamon and Cerro Azul intrusives in Central Panama are the most probable sources indicating also that the arc was uplifted and laterally continuous between these two areas. New and previous low temperature thermochronometers analyzed in intrusive and sedimentary rocks (recent sands and middle late Eocene sedimentary rocks) suggests 4 e vents of surface exhumation in Azuero Peninsula and Central Panama at:

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90 (1) 47 42 Ma, (2) 32 28 Ma, (3) 22 15 Ma and (4) 9 0 Ma. These episodes are associated to land emergence of Panama based on the presence of unroofed and volca nic zircons deposited in sedimentary formations from the middle Eocene to the late Miocene Most of the Hf isotopic results display positive isotopic values, indicating that there is little effect of crustal or other lithospheric assimilation within the volcanic plumbing system. These Hf isotopic values are consistent with data from the Aleutian arc and the Mariana arc, suggesting a similar island arc origin for the Panamanian basement complex. These data also exclude the South American continent as a sed iment source for Eocene Miocene basin strata in Panama.

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91 APPENDIX A DESCRIPTION OF THE VOLCANICLASTIC BASEMENT COMPLEXES Table A. Description of volcaniclastic basement complexes located between Costa Rica and Panama Rock Unit Sub unit Lithology Age Geo chemistry Characteristics Origin Correlations Nicoya Complex Coniacian (89 85 Ma) Oceanic plateau (not part of the CLIP) Golfito Complex Volcanic rocks, hemipelagic sediments, and volcano sedimentary deposits. The lavas include basalt, basaltic a ndesite, basaltic trachyandesite, and trachyandesite. Occur as massive to thin pillowed lava flows. Pervasive low T alteration. L. Cretaceous to E. Cenozoic Plateau like. Autochtonous sequence. Composed of: (1) proto arc that developed on the top of the CLIP(extension of the Azuero Plateau in Costa Rica?) in the L. Campanian to Maastrichtian, and (2) younger forearc sediments. Azuero Protoarc Group (Buchs et al., 2010), Middle volcaniclastic Unit (Protoarc)(Montes et al., 2012a) Osa Igneous Complex (1) Inner Osa Igneous Complex 99% of basaltic, massive columnar lava flows and pillow lavas. Intrusive rocks (dolerites and gabbros). Occasionally, lenses and layers, 1 3 m thick, of red cherts and black shales are observed between lava flows. Low T submarin e alteration in the zeolite facies. Devoid of greenschist metamorphism. Strong deformation is locally observed and associated with intensive veining of the rocks. Deformation seems to have predominantly ocurred in brittle mode. Coniacian Santonian (89 84 Ma) (Defined by radiolarian associations). Loss of Argon in Ar/Ar ages. Tholeiitic. Plateau like affinities (oceanic, intra plate). Also, NMORB like and OIB like Orientation of the pillow lavas indicates that the volcanic sequences are in both overtu rned and normal position. Almost devoid of detrital material (indicative of submarine volcanism). Absence of carbonate banks indicates that the lavas probably formed below the CCD. Pacific oceanic Plateau distinct from CLIP. Originated in the Pacific befo re being accreted to the CLIP margin in the Paleocene. Azuero Plateau (Buchs et al., 2010). (Part of the CLIP) Are highly similar but (1) have different sedimentary facies and faunal assamblages (2) IOIC contains NMORB like and OIB like rocks, not observe d in Azuero Plateau (3) different Mg# (4) No protoarc crosscut IOIC. Lower volcaniclastic Unit (Plateau) (Montes et al., 2012a)

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92 Table A Continued Rock Unit Sub unit Lithology Age Geochemistry Characteristics Origin Correlations Osa Igneous Complex Espe ranza Formation Arenite, microbreccia and breccia Crops out within the volcanic sequence. This deposit constitutes a unique ocurrence of detrital material in the Inner Osa Igneous Complex Product of submarine erosion of the plateau like lavas prior to ac cretion. (2) Outer Osa Igneous Complex a. Guerra Unit Metamorphosed/altere d igneous rocks, marble, recrystallized micritic limestones and metamorphosed volcniclastic sediments. Prehnite pumpellyte to greenschist metamorphic facies. Protoliths di fficult to identify. No preserved fossils. Stronger deformation that IOIC. By analogy with other units forming the OOIC and the possible role of the unit in the construction of the Osa IC, probably encompassed between the Late Cretaceous and the Eocene. OI B like, intraplate affinities Highest metamorphic and deformation grades in OIC and Osa melange. Marks the contact between I and O IC. Remained close to the decollement zone for a relatively long time, potentially recording some of the processes that occu r at the interface between the overriding and subducting plates. b. Ganado Unit Pillowed and massive basaltic/basaltic andesitic flows locally intruded by aphyric basaltic dykes, dolerites and gabbros. Low T submarine alteration to zeolite facies in re sponse to hydrothermal circulation. Red radiolarian chert interbedded with coarse lava flows. Coniacian Santonian (89 84 Ma) (Defined by radiolarian associations). Tholeiitic. Plateau like affinities. Discriminative geochemical differences in terms of Nb content with IOIC. Also, NMORB like tholeiites, similar to NMORB of IOIC. Underwent a significant tectonic dismemberment. Lower Nb Y ratios than IOIC, indicating that these 2 units have dissimilar origin. Accreted seamount

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93 Table A Continued Rock Un it Sub unit Lithology Age Geochemistry Characteristics Origin Correlations Osa Igneous Complex c. Riyito Unit Volcano sedimentary sequences including small, well formedpillow lavas, sheet flows and minor occurrences of sediments and hyaloclastites. Low T oceanic alteration. No fossils. Shows indications of dismemberment. Paleocene older (?). Loss of Argon in Ar/Ar ages Tholeiitic. Oceanic origin. Vesiculated hyaloclastites are locally observed between pillow lavas, possibly indicating eruption under s hallower conditions. Various seamount fragments generated very close to a MOR. d. Vaquedano Unit Vesiculated, small shaped pillow basalts and lava flows, reddish pelagic limestones, detrital sediments and hyaloclastites. Limestones locally occur as xeno liths embedded in massive lava flows. Limestones form interbeds within the pillowed and massive lava flows. Low T, oceanic oxidization/alteratio n. Campanian M. Eocene (Foraminifera, age well constrained by fossil assamblages in pelagic limestones). K Ar ages bradly similar to biochronological ages. OIB like affinities Devoid shallow water limestones. Interbedded lavas and limestones. Superficial layers of seamounts peeled off at shallow level during subduction. Azuero Marginal Complex (1) Azuero Plate au Massive and pillowed lava flows with scarse occurrences of interbedded radiolarites. Rare gabbroic intrusives. Coniacian E. Santonian ( 89 85 Ma.)( radiolarite ages), in broad agreement with Ar/Ar ages (93 82 Ma, Lissina, 2005). Tholeiitic. Plateau like affinities. Includes 2 geochemical groups: Trace elements of group I display typical plateau like affinities, whereas group II has a more enriched character. Dykes of the Azuero Protoarc and Azuero Arc crosscut the plateau. Oceanic plateau (part of t he CLIP) Lower volcaniclastic Unit (Plateau) (Montes et al., 2012a), Inner Osa Igneous Complex (Buchs et al., 2009)

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94 Table A Continued Rock Unit Sub unit Lithology Age Geochemistry Characteristics Origin Correlations Azuero Marginal Complex (2) Oc Form ation Foraminifera bearing pelagic and hemipelagic limestones.Overlay s the Azuero Plateau and is locally interbedded with lava flows of the Azuero Protoarc group Campanian Maastrichtian. Larger benthic foraminifera evidence for nearby shallow water envi ronments. Crosscut by basaltic dykes of the Azuero Protoarc Group. Golfito Formation (Limestones of the Golfito Complex)(Buch s et al., 2010) (3) Azuero Protoarc Group Mafic lava flows, locally nterbedded with hemipelagic limestonesof the Ocu Formation. Basaltic to basaltoc trachyandesitic lava flows and dykes. Late Campanian to Maastrichtian (?) Empleced within and on top of the Azuero Plateau through the Late Campanian (75 73 Ma). Autochtonous sequence. Evolved rapidly (possibly in less than 5 Ma) to ward a mature volcanic arc (Azuero Arc Group). Intermediate between the Azuero Plateau and Azuero Arc Group. Primitive island arc developed on top of the Azuero Plateau. Chagres Igneous Complex (Wegner et al., 2010), Golfito Complex (Buchs et al., 2010), M iddle volcaniclastic Unit (Protoarc)(Mon tes et al., 2012a) (4)Azuero Arc Group Intermediate to silic lavas and related intrusives. Volcanic rocks ranging in composition from basalt to dacite. Large intrusives (granodiorite) Late Cretaceous (Maastrichtian ) 40 Ma). Late Campanian to Maastrictian (Using planctonic forams and radiolarians, Corral et al., 2013) Suprasubduction geochemical signatures (Depleted in Nb and Ti, enriched in mobile elements such as Pb and Ba) At least in part emplaced contemporaneousl y with Azuero Protoarc. Extinct volcanic arc. Island arc. Intra oceanic volcanic arc. Upper volcaniclastic Unit (Arc)(Montes et al., 2012a)

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95 Table A Continued Rock Unit Sub unit Lithology Age Geochemistry Characteristics Origin Correlati ons Azuero Accretionary Complex (1) Submarine massive and pillowed lava flows with minor occurrences of pelagic and hemipelagic calcareous sediment and hyaloclastice, (2) Clastic deposits composed of basaltic breccias crosscut by rare basaltic dykes (3) Large gabbroic intrusions. Paleocene E. Eocene (biochronologic data from shallow marine limestones) Typical OIB affinities. Middle Eocene age of accretion Undifferentiated metamorphic rocks Deformed metabasalt, metasediment and ultramafic rocks in th e greenschist to amphibolite facies (Tournon et al., 1989).Are cut by younger unmetamorphosed dolerites (presumably proto arc and early arc dykes) Undefined Azuero Melange (1) Deformed rocks initially pertaining to adjacent units; (2) other volcano s edimentary assemblages, which include abundant vesicullar illow basalt, reddish siliceous pelagic limestone, and minor red chert, black shale and carbonate sediment with basaltic fragments. Some of the pelagic sediments contain radiolarians and early Maas trichtian planktic foraminifers. Former decollement zone at the contact with the Azuero Plateau, which locally contains accreted pieces of seamounts.

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96 Table A Continued Rock Unit Sub unit Lithology Age Geochemistry Characteristics Origin Correlations San Blas Complex (1) Lower Volcaniclastic Unit Drak gray diabase, massive basalt, amygdular pillow basalt interbedded with lenticular volcanic breccia layers and discontinuous layers of stratiform chert, tuffaceous siltstone, and micritic limestone. Cross cut by very fine grained basaltic and andesitic dykes. Late Cretaceous (?) to Eocene (?) (Ar/Ar, Wegner et al., 2011) Tholeiitic. Moderately depleted pattern. small Nb Ta positive anomaly, and no Ti and Zr Hf negative anomalies. Uppermo st layers of and o ceanic Plateau Azuero Plateau (Buchs et al., 2010), Inner Osa Igneous Complex (Buchs et al., 2009) (2) Middle Volcaniclastic Unit Massive basalt and andesite, pillow basalt, amygdular basalt, porphyritic andesite, and diabase sills and dikes. Chert beds and tuffaceous siltstone that are up to 2m thick and continuous for >1km are interbedded with the volcanic layers. Fine grained basaltic and rare medium grained dioritic dikes crosscut the sequence. Late Cretaceous (?) to Eocene (?) (Ar/Ar, Wegner et al., 2011) Tholeiitic. Proto arc Golfito Complex, Azuero Protoarc Group (Buchs et al., 2010) (3) Upper Volcaniclastic Unit Lavas and volcanic breccia. The lavas are stratiform, massive andesitic lavas with centimeter scale layering. Interbedded breccias probably reprecenting brecciated top flows or bases of lava flows. Diabase dikes and sills intrude these layers. Late Cretaceous (?) to Eocene (?) (Ar/Ar, Wegner et al., 2011) Calc alkaline. Arc Azuero Arc Group (Buchs et al., 2010)

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97 APPENDIX B IS OTOPIC AGES FROM THE GRANITOIDS IN PANAMA Table B Isotopic ages from the granitoids in Panama 2. CM 3. VR 4. Parita 5. Pedasi 6. PTQ 7. CA 8. Mamoni 9. CH 10. Chepo 11. SB 1 12. SB 2 13 SB 3 14. SB 4 15. Mand U Pb Zn 67.61.4 5 67.61.0 66.0 1.0 49.2 0.9 5 48.11.2 5 41.1 0.7 28.60.6 7 29.1 0.6 26.10.8 28.30.5 54.11.2 5 54.71.2 58.51.3 58.7 1.4 39.40.8 5 49.7 1.0 58.3 1.0 5 59.0 1.9 5 58.6 1.6 5 49.71.6 49.51.1 49.5 0.9 42.51.3 1 43.8 0.8 Ar/Ar Hbl 65.7 1.4 2 54.81.2 2 Dacites: 67.9 1.3 66.01. 1 65.6 1.3 40.8 1.4 2 30.10.4 7 28.60.4 31.4 0.3 WR 49.4 1.0 8 61.5 2.3 47.2 1.3 8 68.5 5.0 8 49.9 2.1 8 Ar/Ar Biot Ar/Ar Kspar 500.3 4 49.5 0.2 (Plg) 50.7 0.1 4 (Plg) ZFT 41.6 5.4 6 46.4 5.8

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98 Table B. Continued 2. CM 3. VR 4. Parita 5. Pedasi 6. PTQ 7. CA 8. Mamoni 9. CH 10. Chepo 11. SB 1 12. SB 2 13 SB 3 14. SB 4 15. Mand ZnHe 48.80.9 1 43.0 0.8 32.90.6 1 32.70.6 22.30.7 3 20.70.3 23.40.4 19.5 0.3 41.42.0 5 50.91.6 50.11.8 44.21.6 4 2.81.5 40.11.5 47.71.9 43.91.6 40.21.5 41.31.6 48.91.8 48.81.8 51.01.8 50.6 1.9 32.8 0.7 6 AFT 50.19.4 5 85.530 47.3 3.6 44.8 8.2 35.82.4 5 45.43.6 45.44.2 46.32.1 42.64.8 45.7 3.7 38.15.4 6 37.8 5.2 AHe 10.40.2 9 12.50. 4 10.40.5 12.80.3 16.60.4 16.6 0.4 33.2 1.1 1 29.9 0.8 8.7 0.5 9 17.5 0.5 11.40.5 5 6.21.6 12.07.4 12.70.8 23.30.8 12.6 1.2 34.00.7 3 23.80.4 24.11.7 19.40.9 27.0 0.6 22.90.9 20.60.7 18.40.6 3.9 0.2 6 Note: ( 1 : Cardona, pers. com m.; 2 : Corral, 2013; 3 : Farris et al., 2011; 4 : Lissina, 2005; 5 : Montes et al., 2012, Montes et al., 2012b, Montes, pers. comm.; 6 : Villagomez and Spikings, 2013; 7 : Whattam et al., 2012; 8 : Wegner et al., 2011 ; 9: This study ). Locations of the intrusives in Figure 2 2. SB = San Blas, CA = Cerro Azul, CH = Chulugant, CM = Cerro Montuoso, PTQ = Petaquilla, VR = Valle Rico, ZFT = Zircon fission track, ZnHe = zircon (U Th)/He, AFT = Apatite fission track AHe = apatite (U Th)/He

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99 APPENDIX C IGNEOUS AND DETRI TAL U Pb RESULTS Table C U Pb geochronological analyses Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300332_01 0.00800852 7.86147E 05 0.056286108 0.001465041 51.41895316 1.005441452 55.59862 389 2.814525279 0.377489773 0.075175794 300332_02 0.005264743 5.39473E 05 0.061507157 0.006938516 33.8485989 0.691850302 60.60487811 13.23018725 0.092463918 0.441487221 300332_03 0.009982295 0.000229562 0.107543152 0.007236017 64.02888557 2.930019897 103 .7102094 13.22397207 0.342701159 0.382617334 300332_04 0.004434087 6.13773E 05 0.034943004 0.002380523 28.51985806 0.787784535 34.87293752 4.665463572 0.20415226 0.182177927 300332_05 0.008565642 0.00013095 0.103151913 0.018457642 54.98075937 1.673809072 99.67657433 33.69539804 0.088022033 0.448408418 300332_06 0.006037193 6.63748E 05 0.067460143 0.004887645 38.79998627 0.850567902 66.2830022 9.276698693 0.152783997 0.414631429 300332_07 0.006037193 6.63748E 05 0.067460143 0.004887645 38.79998627 0.8505 67902 66.2830022 9.276698693 0.152783997 0.414631429 300332_08 0.008354153 0.000142697 0.083284685 0.005096118 53.62889376 1.824332299 81.22428725 9.53048945 0.28000143 0.339743129 300332_09 0.006611939 0.00021067 0.194150545 0.016961605 42.48163317 2.69 7925952 180.1554385 28.64042721 0.365887857 0.764194556 300332_010 0.008215977 0.000132367 0.060567257 0.003386368 52.74550374 1.692510862 59.70546566 6.473532346 0.288929838 0.116571604 300332_011 0.008331441 0.000103764 0.067181596 0.003490789 53.48369 653 1.326641033 66.01802268 6.631531613 0.240422375 0.189862187 300332_012 0.008664256 0.000154878 0.080397472 0.006674196 55.61101538 1.979444685 78.51457327 12.50590915 0.216503841 0.291710913 300332_013 0.007850608 0.00010161 0.05449443 0.001149927 50 .40902457 1.299724248 53.87495071 2.213233262 0.613599064 0.064332795 300332_014 0.00852358 0.000146235 0.087018872 0.004921225 54.71191691 1.869250844 84.71821435 9.17260694 0.304148887 0.354189446 300332_015 0.008353625 0.00012399 0.059143621 0.0011473 54 53.62551712 1.585194371 58.34163554 2.198595285 0.765290288 0.080836239 300332_017 0.007951739 5.79611E 05 0.064070342 0.001970629 51.05582948 0.741341934 63.05360882 3.757253322 0.237421552 0.190279027 300332_018 0.007698047 9.64326E 05 0.054690365 0 .00147367 49.43317673 1.233691916 54.06359142 2.835370133 0.465239841 0.08564756 300332_019 0.008529197 0.00019429 0.092746969 0.008023174 54.74781573 2.483446473 90.05450396 14.85507984 0.264537442 0.392059105 300332_020 0.008064509 9.18248E 05 0.058838 12 0.002050944 51.77698998 1.174319603 58.04872982 3.92954139 0.327131199 0.108042672 300332_021 0.00830107 0.000115492 0.066883155 0.003693228 53.28953233 1.476632376 65.73404211 7.017404689 0.252733874 0.189316059 300332_022 0.008201177 0.000103632 0.0 66947305 0.003631192 52.65087474 1.325133093 65.79509102 6.899318053 0.233736226 0.19977503 300332_023 0.004423606 8.17798E 05 0.048108028 0.007441198 28.45259272 1.049652875 47.70703713 14.36605553 0.121747695 0.403597573 300332_024 0.008902535 0.000148 224 0.078409751 0.007343088 57.13363501 1.893964164 76.64483997 13.78029021 0.179121801 0.254566452 300332_025 0.007865523 0.000111725 0.079164694 0.010383159 50.50441951 1.429081225 77.35537693 19.44458569 0.110189575 0.347111713 300332_026 0.008060432 6.27574E 05 0.067143607 0.005318793 51.75091744 0.802600261 65.98187928 10.09596888 0.099430833 0.21567985

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100 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300332_027 0.007791 448 4.05889E 05 0.108928489 0.016736704 50.03062734 0.519232621 104.9794126 30.41916858 0.036131945 0.523424392 300332_028 0.004355309 6.13059E 05 0.033772587 0.001883976 28.01426106 0.786930041 33.72404946 3.697368959 0.253114845 0.169309098 300332_028R im 0.004235565 3.48291E 05 0.034693338 0.003147309 27.24566535 0.447128927 34.6279735 6.167453128 0.091953839 0.213189147 300332_029 0.008830242 0.000126096 0.081205627 0.008509552 56.67171522 1.611354922 79.27377426 15.9196234 0.137778139 0.285113952 30 0332_030 0.007833502 0.000103272 0.052124642 0.005095112 50.29961544 1.321006644 51.59060625 9.810134321 0.136274477 0.025023757 300332_031 0.008218206 7.24522E 05 0.079469521 0.006124292 52.75975028 0.926436998 77.64213284 11.48826187 0.11550858 0.320475 258 300332_032 0.004577972 8.70228E 05 0.044540546 0.006067364 29.44320874 1.116772275 44.24522278 11.76127257 0.141501099 0.334544909 300332_032Rim 0.004648205 7.85229E 05 0.040215422 0.003507002 29.89386421 1.007626377 40.03231641 6.834701553 0.1949574 84 0.253256696 300332_033 0.00804646 9.51264E 05 0.062590368 0.002706455 51.66157519 1.216562197 61.64044157 5.165594094 0.274005994 0.161888301 300332_034 0.005733564 0.000111786 0.096566609 0.009763857 36.85418334 1.432899118 93.59735381 18.00105187 0. 194266203 0.606247593 300332_035 0.00794807 6.8874E 05 0.071104664 0.00657442 51.03236492 0.880919944 69.74364115 12.42607512 0.09505543 0.268286484 300332_036 0.00915714 0.000131455 0.17387807 0.021992282 58.7601828 1.679282577 162.7706947 37.69193053 0 .115321045 0.639000233 300332_037 0.004259605 4.1263E 05 0.040350125 0.005602929 27.39997945 0.529712372 40.16378861 10.90703305 0.071771219 0.317793953 300332_038 0.008048405 9.0151E 05 0.07406273 0.007156351 51.67401271 1.152932186 72.54381358 13.48518 87 0.11731453 0.287685467 300332_039 0.008095388 0.000164784 0.055261062 0.00163083 51.97444579 2.107228978 54.612842 3.135820424 0.690053282 0.048310912 300332_040 0.008300724 0.000102894 0.060653512 0.002125598 53.2873222 1.315562837 59.78803825 4.0654 6971 0.354186213 0.108729375 300332_041 0.00831887 4.87652E 05 0.086251003 0.008327486 53.40333437 0.62349881 84.00073238 15.50822766 0.062112682 0.364251562 300332_042 0.008286691 0.000118516 0.063864934 0.003670636 53.19760772 1.515305595 62.85759085 6 .994304504 0.249644579 0.153680454 300332_043 0.009699199 0.00043275 0.108643175 0.008180533 62.22177346 5.524415807 104.7181469 14.92898414 0.593425081 0.405816706 300332_044 0.008246605 0.000109775 0.056619189 0.001842921 52.94132256 1.403606273 55.918 7395 3.538731388 0.409393016 0.053245423 300332_045 0.008027636 0.000116558 0.059982188 0.00228543 51.54119496 1.490661481 59.14519649 4.373603647 0.381584636 0.128564989 300332_046 0.004487177 6.129E 05 0.030108673 0.000907622 28.86056388 0.786622163 30 .11910302 1.788416 0.453499091 0.041785412 300332_047 0.008244379 0.000116736 0.070679711 0.002482344 52.92709053 1.492613799 69.34073579 4.702591112 0.403627628 0.236709996 300332_048 0.008225164 0.000146563 0.066813624 0.00344957 52.80423827 1.87399738 6 65.66786925 6.555610012 0.345829932 0.19588927 300332_049 0.008699021 0.00013985 0.059105623 0.002012267 55.83318998 1.787337255 58.30520843 3.854533801 0.472647015 0.042397901 300332_050 0.004511407 9.47565E 05 0.033249655 0.001331906 29.01605824 1.21 6096441 33.21031589 2.615932293 0.524831677 0.12629382 300332_051 0.004502934 6.6537E 05 0.033185337 0.001786537 28.96168632 0.853948149 33.14711124 3.508298345 0.275224785 0.126268165 300332_052 0.008836899 0.000342922 0.077483476 0.006244709 56.7142505 8 4.381620931 75.77237025 11.73502428 0.482519332 0.251518061

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101 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300332_053 0.008975316 0.000271419 0.142149048 0.01555 5942 57.59864432 3.467657564 134.9493529 27.47075011 0.277861412 0.573183249 300332_054 0.008658092 0.000146856 0.062695405 0.005159958 55.5716191 1.876936458 61.74080125 9.836100664 0.207258434 0.099920669 300332_055 0.008651863 0.000127546 0.064620582 0.001374595 55.5318109 1.630168702 63.57850982 2.620219387 0.693254642 0.126563188 300332_056 0.01075915 0.000150222 0.084301519 0.003784443 68.98525085 1.915967236 82.17688986 7.075106033 0.311639406 0.160527358 300332_057 0.004711504 3.77861E 05 0.0434 14294 0.003883358 30.30000078 0.484860507 43.14987429 7.54365085 0.090951874 0.297796314 300332_058 0.008400194 0.000199844 0.05879025 0.001794136 53.92321627 2.554755203 58.0028253 3.438077805 0.77984069 0.07033466 300332_059 0.008765562 0.000153977 0.0 62360279 0.002186385 56.25841526 1.967732881 61.42056113 4.174900278 0.501462187 0.084045892 300333_01 0.009391003 0.000194792 0.066290424 0.001942146 60.25386249 2.487737443 65.16979566 3.695293857 0.708292445 0.075432693 300333_02 0.0051375 17 0.00013903 0.044823517 0.002313109 33.03271353 1.783152817 44.52024393 4.490665843 0.525041496 0.258029368 300333_03 0.00909245 9.7956E 05 0.078170305 0.003062959 58.34695208 1.251448607 76.41937526 5.760703846 0.275494298 0.236490067 300333_04 0.0086 00047 6.51924E 05 0.070437609 0.004247809 55.20065253 0.833293507 69.11112301 8.04231757 0.12656777 0.201276869 300333_04Rim 0.011264685 0.002268354 0.307604888 0.129030624 72.20854095 28.88640555 272.3089998 191.0991887 0.485369353 0.734828665 300333_05 0.00567786 7.09732E 05 0.081797996 0.005921125 36.4971415 0.909817852 79.82989938 11.08434559 0.173716416 0.542813635 300333_06 0.008317083 7.10051E 05 0.065605279 0.001521303 53.3919079 0.90784479 64.5171844 2.896992178 0.368477182 0.172438965 300333_0 7 0.008460902 4.10443E 05 0.080675861 0.005772819 54.3112852 0.52470942 78.77616284 10.818647 0.068829488 0.310561936 300333_08 0.008643431 7.30754E 05 0.077298572 0.006226053 55.47792315 0.934011141 75.59811661 11.70206898 0.106126484 0.266146756 300333 _09 0.008643431 7.30754E 05 0.077298572 0.006226053 55.47792315 0.934011141 75.59811661 11.70206898 0.106126484 0.266146756 300333_010 0.008569747 5.75773E 05 0.076348035 0.001935146 55.00699753 0.735981647 74.7018597 3.647613821 0.265428451 0.26364621 3 00333_011 0.009653619 0.000402728 0.177550953 0.035340487 61.93077438 5.141461595 165.9425504 60.04733604 0.212411052 0.626793886 300333_012 0.008661695 0.000104105 0.060549565 0.001159602 55.59464928 1.330570924 59.68852809 2.2191085 0.627798861 0.068587 364 300333_013 0.010841895 0.000316389 0.091215335 0.003472989 69.51294309 4.034637766 88.63038042 6.452686499 0.766799188 0.215698469 300333_014 0.008549682 8.09464E 05 0.070297045 0.003841053 54.87875169 1.034706132 68.97778666 7.274541994 0.174054819 0.204399643 300333_015 0.004717834 5.6626E 05 0.061932888 0.01408561 30.34061619 0.726597171 61.01200803 26.75789599 0.056067409 0.502710742 300333_016 0.009133736 0.00011461 0.082367115 0.006195243 58.61068737 1.464148389 80.36391117 11.58995203 0.16790 4359 0.270683986 300333_017 0.007167564 8.25424E 05 0.051974744 0.001823702 46.03880064 1.05655423 51.44594051 3.517307577 0.328684689 0.105103334 300333_018 0.00963637 0.000420108 0.322764432 0.058075276 61.82064073 5.363393929 284.0124007 87.25349685 0 .244823264 0.782331192 300333_019 0.008258739 6.30827E 05 0.063963063 0.001395326 53.01890024 0.806601355 62.9512386 2.661352507 0.350443121 0.157778283

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102 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error 207Pb/235U 2 s error RHO Discordance 300333_020 0.008252088 6.93247E 05 0.05844953 0.001666586 52.97637708 0.886417744 57.67603766 3.194873133 0.295025786 0.081483763 300333_021 0.008643579 6.68092E 05 0.082792998 0.007250441 55.47886744 0.853922108 80.7 6333878 13.55210829 0.089526702 0.313068674 300333_022 0.00834372 6.47697E 05 0.065104568 0.003038859 53.56219788 0.828101322 64.03998415 5.785453389 0.166975447 0.163613193 300333_023 0.004784032 5.17274E 05 0.060872429 0.006881312 30.76532198 0.6636990 97 59.99757924 13.12928912 0.097279939 0.487223945 300333_024 0.00682186 5.92756E 05 0.049352589 0.002088137 43.82580091 0.759005629 48.91196292 4.036860197 0.205964532 0.103986054 300333_025 0.008198775 7.24244E 05 0.081914255 0.011757904 52.63551338 0. 926098747 79.93900923 21.94955147 0.063618875 0.341554094 300333_026 0.006959524 6.75073E 05 0.054813697 0.002073667 44.70713782 0.864287324 54.18231371 3.988178292 0.256932091 0.174875808 300333_027 0.008252966 6.00067E 05 0.062714945 0.003289249 52.981 99012 0.767275999 61.75947021 6.275474204 0.139385512 0.14212363 300333_028 0.006950366 4.27607E 05 0.068709949 0.007062132 44.64851067 0.54747215 67.47107879 13.37466374 0.061345877 0.338257051 300333_029 0.004222651 4.12149E 05 0.032532628 0.001696885 27.16277269 0.529114769 32.50547896 3.334493947 0.187869896 0.164363253 300333_030 0.008348609 7.42362E 05 0.058059162 0.002455875 53.5934519 0.949124843 57.30150311 4.707937606 0.21081592 0.064711238 300333_031 0.007816838 5.46964E 05 0.061232338 0.0018 39307 50.1930285 0.699679512 60.34197969 3.516457883 0.233368974 0.168190557 300333_032 0.00843277 9.22423E 05 0.074907939 0.008791517 54.13145949 1.17922746 73.34249146 16.54094941 0.094896316 0.261935906 300333_033 0.008804396 0.000194445 0.106885714 0 .015931692 56.50656353 2.484752212 103.1073294 29.01951273 0.15030568 0.451963659 300333_034 0.008064898 5.22013E 05 0.0713916 0.006657398 51.77947752 0.667599344 70.01559997 12.57906441 0.070759693 0.26045799 300333_035 0.008101943 6.2825E 05 0.06369286 0.002291143 52.01636548 0.803431346 62.69335302 4.369245207 0.216076286 0.170304937 300333_036 0.008056101 5.96674E 05 0.057551465 0.00179647 51.72322636 0.763086227 56.8141913 3.446574201 0.237712901 0.089607276 300333_037 0.00807459 6.27805E 05 0.0614 43681 0.002466853 51.8414523 0.802883324 60.54416161 4.713895952 0.194230352 0.143741512 300333_038 0.008100325 6.75161E 05 0.055915326 0.000939355 52.00601832 0.863422895 55.24215442 1.80569979 0.49635374 0.058580918 300333_39 0.009176049 8.34119E 05 0. 101398278 0.005778602 58.88097119 1.065559084 98.06125974 10.62623624 0.16032309 0.399549105 300333_040 0.008521938 5.02859E 05 0.065628148 0.002483864 54.70142162 0.642811976 64.53897443 4.727748857 0.156450719 0.152428093 300333_041 0.009325931 0.00019 4753 0.138390874 0.014755103 59.83828511 2.48739278 131.6029562 26.15105814 0.19738074 0.545311999 300333_042 0.008445171 4.60387E 05 0.06682445 0.002459327 54.21072527 0.588565383 65.6781725 4.675854704 0.148654624 0.174600583 300333_043 0.0085019 7.765 74E 05 0.061371281 0.001363107 54.57333863 0.992713097 60.4749047 2.606284129 0.411540137 0.097587026 300333_044 0.007103256 4.03031E 05 0.05274056 0.001323114 45.62719182 0.515928562 52.18481196 2.550591525 0.226520872 0.125661469 300333_045 0.005111645 6.70618E 05 0.057081973 0.004938903 32.86678837 0.860162881 56.36334291 9.465577293 0.152869462 0.416876525 300333_046 0.008554213 6.97864E 05 0.063979542 0.001637876 54.90770924 0.892053316 62.96696398 3.123572509 0.319029031 0.127991795 300333_047 0.0 0859601 6.8287E 05 0.11033046 0.01233854 55.17485323 0.872850833 106.2622423 22.44126914 0.072652816 0.480767091

PAGE 103

103 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300 333_048 0.008267767 8.54694E 05 0.072796411 0.005774824 53.07661922 1.092824718 71.34603293 10.90166986 0.131455373 0.256067688 300333_049 0.00863476 7.14832E 05 0.070137417 0.005597223 55.42250601 0.913668618 68.82634539 10.59345582 0.104887414 0.1947486 72 300333_050 0.004943926 5.02792E 05 0.037137725 0.001303295 31.79104368 0.645015143 37.02379099 2.550184341 0.290280758 0.141334725 300333_050Rim 0.004871179 4.21102E 05 0.03623505 0.002062224 31.32439555 0.540258439 36.13971006 4.037230867 0.152711615 0.133241648 300333_051 0.007099026 3.76378E 05 0.067794961 0.00754665 45.60012148 0.481813065 66.60141966 14.30125061 0.049241395 0.315328086 300333_051Rim 0.007067448 5.18584E 05 0.052704544 0.002899161 45.39799113 0.663870999 52.15007502 5.584784128 0 .134183429 0.129474097 300333_052 0.008593965 7.93928E 05 0.087730481 0.007024184 55.16178415 1.014802671 85.38267641 13.07115503 0.116536397 0.353946415 300333_053 0.008605298 4.77376E 05 0.082458643 0.006693212 55.23421426 0.610187978 80.449767 12.5176 2297 0.069517925 0.313432266 300333_054 0.008613749 0.000102389 0.103373874 0.006902432 55.28822363 1.308697682 99.88084428 12.663752 0.178972713 0.446458187 300333_055 0.008598769 7.14283E 05 0.068116922 0.00234234 55.19248461 0.912999582 66.90751588 4. 448291592 0.242051698 0.175092904 300333b_01 0.008791808 0.000120172 0.066844063 0.003390243 56.42613004 1.535718128 65.69683889 6.442857952 0.270208128 0.141113469 300333b_02 0.009096232 0.000149688 0.094386396 0.004013351 58.37111149 1.912304655 91.576 64414 7.433258657 0.387584001 0.362598269 300333b_03 0.009131759 0.000283432 0.074435105 0.00275761 58.59805579 3.62054146 72.89576559 5.205156416 0.838089942 0.196139099 300333b_04 0.005147835 6.25638E 05 0.059892092 0.004707995 33.09888669 0.802441992 59.05889184 9.000142674 0.155734166 0.439561332 300333b_05 0.009200859 0.000188528 0.069749059 0.002158779 59.03944309 2.408195584 68.4578098 4.093796871 0.662366089 0.137579142 300333b_06 0.010022629 0.000227923 0.121601527 0.00936042 64.28631277 2.9089 8632 116.5170059 16.87674379 0.296492799 0.448266695 300333b_07 0.00926366 9.5419E 05 0.076198946 0.00500061 59.44057204 1.218832522 74.56121261 9.413718517 0.157896079 0.202794993 300333b_08 0.00508476 4.99912E 05 0.049375893 0.002813396 32.69435884 0.6 4123074 48.93451058 5.436959879 0.173360876 0.331875226 300333b_09 0.009192443 0.000127788 0.086846343 0.0043324 58.98568525 1.632386323 84.55705064 8.078563516 0.279359614 0.302415531 300333b_10 0.01048298 0.000470918 0.131208367 0.010153604 67.22371099 6.006890805 125.1765787 18.14569624 0.5814131 0.462968938 300333b_11 0.008773941 0.000147629 0.064114755 0.002135427 56.31195241 1.886596831 63.09598709 4.070977377 0.505600251 0.107519273 300333b_12 0.041174901 0.01878411 1.499545292 0.77192688 260.103 0636 230.5221481 930.15416 546.514889 0.889624911 0.72036564 300333b_13 0.008782312 0.000129287 0.062516564 0.00122352 56.36544694 1.65220887 61.56991691 2.337024887 0.75238322 0.08452943 300333b_14 0.008592736 9.64925E 05 0.063545035 0.001086888 55.1539 2716 1.233364285 62.5522396 2.074172133 0.656724204 0.118274141 300333b_15 0.00869301 0.000109196 0.060706933 0.001167434 55.79477679 1.395592191 59.83917484 2.233756159 0.653405978 0.067587798 300333b_16 0.008992184 0.000114896 0.069232947 0.001551475 5 7.70641072 1.468006356 67.96783344 2.944390951 0.570443087 0.150974692 300333b_16 0.009484598 0.000358318 0.076842975 0.004482793 60.851554 4.575374302 75.16863578 8.435906217 0.648242596 0.190466165 300333b_18 0.008293489 0.000116119 0.058669801 0.00167 1538 53.24106758 1.484659772 57.88731418 3.203694107 0.491794396 0.080263641

PAGE 104

104 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300333b_19 0.008798231 0.0001293 0.0674 10677 0.003706833 56.46716724 1.652340044 66.23595046 7.039735234 0.268024516 0.147484608 300333b_20 0.010344311 0.000620839 0.118966796 0.012249374 66.33903801 7.919734465 114.1291058 22.10895459 0.584105743 0.418736898 300333b_21 0.009296456 0.00011336 5 0.062230463 0.001336389 59.65003431 1.448006008 61.2964845 2.553166304 0.568104028 0.026860434 300333b_22 0.009292462 0.00015718 0.071784265 0.007205031 59.62452565 2.007620635 70.38765104 13.60537824 0.169958237 0.152912126 300333b_23 0.009209852 0.00 0100704 0.077541347 0.003319876 59.0968891 1.28641019 75.82690131 6.24679928 0.25599229 0.220634259 300333b_24 0.00905747 0.000104133 0.072467244 0.002564422 58.12348981 1.33040107 71.03444953 4.849808566 0.325372125 0.181756314 300333b_25 0.007645288 9. 55818E 05 0.05739623 0.00115868 49.09566668 1.222872671 56.66514279 2.223953756 0.619530219 0.133582582 300333b_26 0.008831599 0.000134815 0.062376064 0.00113464 56.68038601 1.722765003 61.43564717 2.167634264 0.839332703 0.077402312 300333b_27 0.0088382 86 0.00011476 0.082732527 0.005434019 56.72311764 1.466494295 80.70663322 10.16600319 0.198621321 0.297169076 300333b_28 0.009283675 0.000124224 0.075918396 0.003085983 59.56840625 1.586718333 74.29649625 5.816075108 0.329740906 0.198233978 300333b_29 0. 008800427 0.000127474 0.066946449 0.001502152 56.48120543 1.629005864 65.79427652 2.856956333 0.645800154 0.141548347 300333b_30 0.008702957 0.00013472 0.063217275 0.001334167 55.85834063 1.721768673 62.23928971 2.546558285 0.733693786 0.102522845 300333 b_31 0.008921197 0.000127569 0.06331644 0.002172928 57.25287081 1.630029972 62.33398417 4.145503024 0.417124262 0.081514336 300333b_32 0.009336363 0.000108 0.068805383 0.001542318 59.9049071 1.379428695 67.56174215 2.928195505 0.516332137 0.11333093 3003 33b_33 0.009250715 0.000104326 0.066687992 0.000992819 59.35788874 1.332611212 65.54829295 1.88915951 0.757658833 0.094440357 300333b_34 0.009321345 7.97143E 05 0.087017697 0.005880129 59.80899524 1.018178543 84.71711735 10.95509426 0.127526878 0.29401522 3 300333b_35 0.008975411 0.000131265 0.068066379 0.001865837 57.59924926 1.677160213 66.85946961 3.544331128 0.533859914 0.138502749 300333b_36 0.009004483 0.000100493 0.067726194 0.001847423 57.78498251 1.283971207 66.53602942 3.510499822 0.409496538 0. 131523431 300333b_37 0.008674568 0.000100162 0.067225292 0.001890997 55.67691563 1.280167204 66.05959562 3.594911288 0.410858655 0.157171413 300333b_38 0.005224976 4.84012E 05 0.045670584 0.003895875 33.59358545 0.620749521 45.34306725 7.551622067 0.1098 23126 0.259124107 300333b_39 0.008718676 0.000132899 0.064661778 0.001503442 55.95879559 1.698471932 63.61779842 2.865539543 0.655846007 0.120390881 300333b_40 0.009085162 0.000107756 0.105392664 0.012682628 58.30039744 1.376656699 101.7368507 23.1659944 6 0.100298894 0.426949065 300333b_41 0.009606118 8.35474E 05 0.094176345 0.003451121 61.62748948 1.066835473 91.38174874 6.394795882 0.237854093 0.32560396 300333b_42 0.009343335 0.00010263 0.070790213 0.002618381 59.94943307 1.310835038 69.4455199 4.959 477222 0.297482671 0.136741533 300333b_43 0.009338368 0.000113404 0.066231315 0.00113092 59.91771196 1.448446026 65.1135093 2.152723481 0.711370641 0.079795996 300333b_44 0.009409649 0.000115276 0.077315526 0.001439233 60.37293768 1.472245589 75.61409579 2.711041602 0.658316182 0.201565038 300333b_45 0.009356394 0.000126104 0.065074638 0.000969418 60.032838 1.610610952 64.01145271 1.847444091 0.904824749 0.062154732 300333b_46 0.009575626 7.66337E 05 0.081089649 0.002646587 61.43280198 0.978584608 79.16 48561 4.965136889 0.245665187 0.223988964

PAGE 105

105 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300333b_47 0.008010797 8.33874E 05 0.062158838 0.004685109 51.43351303 1.0 6647745 61.22801994 8.937416691 0.139187179 0.159967723 300333b_48 0.00867674 0.000147563 0.080341104 0.007560451 55.69079587 1.885943662 78.46159818 14.16150652 0.182064357 0.290215887 300333b_49 0.00710422 7.17387E 05 0.054757311 0.001746273 45.6333676 1 0.918328398 54.12803668 3.359217063 0.317079847 0.156936582 300333b_50 0.00710422 7.17387E 05 0.054757311 0.001746273 45.63336761 0.918328398 54.12803668 3.359217063 0.317079847 0.156936582 300333b_51 0.008953946 6.8948E 05 0.10279949 0.008231302 57.46 210902 0.880987888 99.35215479 15.10059564 0.097323728 0.42163198 300333b_52 0.00843095 8.91789E 05 0.061909283 0.001189075 54.11982007 1.140068744 60.98943911 2.272567317 0.550954115 0.112636206 300333b_53 0.008267043 8.72224E 05 0.057643374 0.000869333 53.07199286 1.115238856 56.90242762 1.668424501 0.699741869 0.067315841 300333b_54 0.008142718 8.53088E 05 0.063731382 0.001580696 52.27708922 1.090907002 62.73012337 3.015308927 0.422731416 0.166635001 300333b_55 0.008572475 0.000119992 0.089300266 0.0 03611941 55.02443103 1.533747476 86.84692119 6.722206425 0.346615933 0.366420476 300333b_56 0.008875964 7.22348E 05 0.06542916 0.001552147 56.96386402 0.923054211 64.34936081 2.956174149 0.343382505 0.114771875 300333b_57 0.007873401 7.61552E 05 0.060066 269 0.002098482 50.55480683 0.974117577 59.22573283 4.015877763 0.277348448 0.146404706 300333b_58 0.007873401 7.61552E 05 0.060066269 0.002098482 50.55480683 0.974117577 59.22573283 4.015877763 0.277348448 0.146404706 300333b_59 0.004924778 4.62839E 05 0.041329454 0.001649191 31.66821884 0.593773644 41.11911666 3.213490585 0.236084855 0.229841947 300333b_60 0.007933833 8.15271E 05 0.056513686 0.000769124 50.94130994 1.042765383 55.8173539 1.477750222 0.755180327 0.087357132 300333b_61 0.008297092 7.841 68E 05 0.062564782 0.001486442 53.26410262 1.002623157 61.6159927 2.83874864 0.398116202 0.13554744 300333b_62 0.008025309 7.28347E 05 0.059982554 0.001771758 51.52631906 0.931505745 59.14554737 3.391414264 0.30766142 0.128821672 300333b_63 0.008295327 9 .26082E 05 0.063185919 0.001706063 53.25281904 1.184066332 62.20934528 3.255933546 0.413823866 0.143973967 300333b_64 0.008182859 4.36404E 05 0.070469093 0.00259677 52.53375035 0.558051759 69.14098552 4.9200657 0.145255712 0.240193787 300333b_65 0.007947 333 5.40675E 05 0.061848532 0.001373482 51.02764775 0.691545271 60.93135116 2.624928264 0.306658805 0.162538713 300333b_66 0.007937363 7.79922E 05 0.070138117 0.005013722 50.96388517 0.997551143 68.82700959 9.491675631 0.138484493 0.259536547 300333b_67 0.007830152 5.7177E 05 0.06287243 0.004558937 50.27818737 0.731401033 61.90992264 8.691416975 0.101750462 0.187881599 300333b_68 0.00791072 5.23813E 05 0.061287943 0.001449431 50.79348827 0.670004016 60.39517866 2.77144256 0.280316338 0.158981074 300333b _69 0.008059801 0.000132426 0.085909319 0.014992481 51.74688446 1.693523897 83.6813054 27.84433818 0.096667974 0.381619536 300333b_70 0.006083008 0.000301237 0.188947787 0.026375226 39.09354337 3.85960856 175.7221076 44.55516776 0.356651389 0.777526323 3 00333_01b 0.008110756 0.00016844 0.046893553 0.002922619 52.0727186 2.153942071 46.52985858 5.661115233 0.334066534 0.119124798 300333_02b 0.008474468 0.000151079 0.050491037 0.001509969 54.3979947 1.931265379 50.01290373 2.916766834 0.596475295 0.08767 9192 300333_03b 0.008509414 0.0002151 0.058183757 0.001746752 54.62136861 2.749470899 57.42105942 3.349268286 0.842234433 0.048757213 300333_04b 0.008132419 0.000114271 0.057906381 0.001214044 52.21123662 1.461255999 57.1548818 2.329035524 0.670428685 0. 086495589

PAGE 106

106 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300333_05b 0.008529648 0.000176283 0.060740147 0.004121454 54.75069981 2.253289097 59.87096825 7.874752547 0.305518643 0.085521724 300333_06b 0.00821992 0.000154894 0.05700554 0.001214018 52.77071046 1.980524508 56.28992621 2.330968793 0.884972092 0.062519459 300333_07b 0.008200651 0.000139401 0.074004989 0.003641023 52.64751187 1.782471396 72.48922825 6.872 580632 0.346174678 0.273719515 300333_08b 0.007985741 0.000120016 0.057340426 0.001876533 51.27328064 1.534945914 56.61155724 3.600759357 0.459649812 0.094296586 300333_09b 0.007888741 0.000118058 0.057126937 0.003561905 50.65292254 1.510051876 56.406529 93 6.830656603 0.240897204 0.102002506 300333_10b 0.008510901 0.000351252 0.061828847 0.002721022 54.63087109 4.489494063 60.91252767 5.197080831 0.938005739 0.103125856 300333_11b 0.007820902 9.87665E 05 0.052305286 0.000965853 50.21902274 1.263395657 5 1.76491853 1.86297869 0.684087415 0.029863773 300333_12b 0.007826828 9.10856E 05 0.058511989 0.003413624 50.25692584 1.165140788 57.73595081 6.538203927 0.200306159 0.12953844 300333_13b 0.007631467 7.1896E 05 0.048988987 0.001818038 49.00724876 0.919859 902 48.56008776 3.516364434 0.254379303 0.009208406 300333_14b 0.007788552 0.00011224 0.04896928 0.002574471 50.01210515 1.43577952 48.54101282 4.977723228 0.274843914 0.030306173 300333_15b 0.008591873 0.000193756 0.056615039 0.00183945 55.14840764 2. 476463076 55.91475138 3.532085698 0.694421263 0.013705574 300333_16b 0.005253428 0.000234127 0.029398342 0.007595366 33.77603618 3.002336082 29.41872024 14.92814373 0.176185257 0.148113715 300333_17b 0.008178166 0.000116212 0.056527432 0.000956425 52.50 374658 1.486019879 55.83056434 1.837432813 0.839989823 0.059587751 300333_18b 0.007948105 0.000114216 0.055968912 0.001613529 51.03258561 1.460822017 55.29368031 3.100501946 0.498824667 0.077062961 300333_19b 0.00827166 5.34507E 05 0.056808829 0.00132676 6 53.1015078 0.683437336 56.10095294 2.547787463 0.277008519 0.053465137 300333_20b 0.006848081 6.9652E 05 0.051086347 0.001244818 43.99367713 0.891843537 50.5881266 2.403523236 0.417731748 0.130355677 300334_01 0.006662728 0.000100337 0.0424 66171 0.001088856 42.80687115 1.284964579 42.22684944 2.119920074 0.587632423 0.013735851 300334_02 0.007116995 0.000146904 0.051774114 0.001235684 45.71513634 1.880425414 51.25227976 2.38433887 0.865025902 0.108037017 300334_03 0.006669606 5.81598E 05 0.041561136 0.003597745 42.85091721 0.744831371 41.34498918 7.00219922 0.10198397 0.036423471 300334_04 0.006465222 6.94972E 05 0.041597231 0.001827952 41.54200951 0.890199754 41.38017457 3.560589495 0.245233065 0.003910929 300334_05 0.004720073 0.0015 00746 0.110163926 0.16470443 30.35498073 19.24297406 106.1099456 280.9122507 0.233707162 0.713928977 300334_06 0.007064755 0.000104312 0.061447248 0.002932507 45.38075198 1.335330349 60.54757373 5.602466645 0.310044102 0.250494294 300334_07 0.006854271 0 .000106184 0.046828326 0.002583164 44.03331033 1.35957794 46.46659687 5.004711458 0.28160502 0.05236636 300334_08 0.006688527 6.7677E 05 0.057748857 0.003133707 42.97207351 0.866693088 57.00368586 6.007187885 0.187237288 0.24615272 300334_09 0.0076479 0. 000178053 0.052570043 0.001758432 49.11237599 2.277905615 52.02034082 3.389610838 0.696364354 0.055900534 300334_10 0.006886442 0.000158501 0.048974622 0.001201698 44.23927433 2.02932385 48.54618364 2.324981828 0.938144537 0.088717773 300334_11 0.0065390 74 5.24264E 05 0.042815938 0.001825258 42.01499992 0.671493861 42.56745511 3.551196033 0.188675163 0.012978347

PAGE 107

107 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 30033 4_12 0.006968301 0.00018765 0.050010589 0.001873867 44.76332512 2.402292465 49.54843049 3.620725681 0.719072159 0.096574308 300334_13 0.006447984 4.30218E 05 0.043741497 0.00214034 41.43160129 0.551088951 43.46822089 4.159898165 0.137059314 0.04685307 30 0334_14 0.006701258 3.76898E 05 0.045406316 0.003605572 43.05359727 0.482668675 45.08643378 6.99164005 0.07197751 0.045087543 300334_15 0.006731341 5.44117E 05 0.045137068 0.002316047 43.24622294 0.69678843 44.82489853 4.495015478 0.158269654 0.035218721 300334_16 0.006230236 4.47497E 05 0.044585306 0.000948703 40.0367999 0.57334732 44.28873007 1.843431083 0.337847959 0.096004789 300334_17 0.007003163 3.08512E 05 0.046867773 0.000779782 44.98649045 0.394974045 46.50485633 1.512019264 0.265008915 0.032649 62 300334_18 0.006293908 4.29252E 05 0.048143732 0.002164218 40.4446832 0.549936502 47.74162423 4.188610353 0.152360255 0.152842329 300334_19 0.006407286 3.74731E 05 0.040446113 0.002328889 41.1709301 0.480033905 40.25746353 4.540268028 0.102402661 0.02 2690614 300334_20 0.006284115 4.10648E 05 0.042593532 0.00338415 40.3819529 0.526106806 42.35088761 6.580647142 0.083395224 0.04649099 070242_01 0.009022114 9.15517E 05 0.058085506 0.002446798 57.89761934 1.169714899 57.32678318 4.690440049 0 .241487751 0.009957582 070242_02 0.008778725 0.000116398 0.059855956 0.000974817 56.34252485 1.487499763 59.02427446 1.866871769 0.814272224 0.04543469 070242_03 0.008561512 0.000154972 0.062703852 0.00260838 54.95436449 1.980853097 61.7488723 4.9781055 89 0.435680656 0.110034525 070242_04 0.008394684 0.000131717 0.062640471 0.002089951 53.88799189 1.683905533 61.68831417 3.98988905 0.47070756 0.126447325 070242_05 0.008572444 0.000160785 0.056561153 0.001285532 55.0242328 2.055125838 55.86296978 2.4692 32934 0.825419148 0.015014185 070242_06 0.008331576 0.000176243 0.059974953 0.002080175 53.48456245 2.253219818 59.1382665 3.981221367 0.61029137 0.09560145 070242_07 0.008355724 0.000106638 0.061739463 0.002859271 53.63893637 1.363351628 60.82705417 5.4 61237004 0.276216836 0.118173038 070242_08 0.008190353 0.000139398 0.053792912 0.00259192 52.58166539 1.782456884 53.19926188 4.988508146 0.353884112 0.011609118 070242_09 0.008702913 0.000168565 0.060395327 0.002573012 55.85806214 2.154273375 59.5408557 2 4.921363186 0.455185439 0.061853219 070242_10 0.008160434 0.000114279 0.056419159 0.001091902 52.39036594 1.461323325 55.72650766 2.097785139 0.723789399 0.059866334 070242_11 0.009971533 0.000168861 0.185471745 0.003731309 63.96019784 2.155354957 172. 749307 6.381536788 0.841910407 0.629751349 070242_12 0.01054155 0.000448789 0.046331397 0.010692045 67.59733868 5.724345153 45.98450414 20.6452352 0.187768226 0.470002557 070242_13 0.008088321 0.000112329 0.055040463 0.000838482 51.92925631 1.436498022 54.40056817 1.613205803 0.911731607 0.045428052 070242_14 0.008308214 0.000253942 0.05838995 0.00181992 53.33521065 3.246546219 57.61888344 3.48876158 0.980737146 0.074344946 070242_15 0.007647163 5.86662E 05 0.05420854 0.004792059 49.10766038 0.75058659 8 53.59964052 9.209759926 0.088059881 0.083806162 070242_16 0.008026064 8.73281E 05 0.061534292 0.001886401 51.53114729 1.116857563 60.63083269 3.605390776 0.355339014 0.150083464 070242_17 0.007807287 0.000106462 0.057412688 0.00105404 50.13193706 1.361 844676 56.6809458 2.023178593 0.742931079 0.115541628 070242_18 0.008336798 3.90445E 05 0.058873384 0.000528708 53.51794217 0.499206067 58.08254397 1.013681358 0.52162203 0.078588186

PAGE 108

108 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/2 35U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 070242_19 0.008228887 0.000110446 0.058439502 0.001806871 52.82804097 1.412219125 57.66641858 3.463605581 0.434503308 0.083902863 070242_20 0.008118215 0.000131644 0.064558374 0.001566843 52.12041502 1.683430467 63.51918037 2.986581843 0.668401653 0.179453911 070242_01B 0.007871647 8.31186E 05 0.04726496 0.001108905 50.54359016 1.063186029 46.89000486 2.14904734 0.450371023 0.077918211 070242_02B 0.009302088 0.000234491 0.060902127 0.00 1748311 59.68600239 2.994946632 60.02600154 3.343672218 0.878330991 0.005664198 070242_03B 0.009212914 0.000147856 0.062867273 0.001634772 59.11644162 1.888675921 61.90499653 3.120917651 0.617471511 0.045045716 070242_05B 0.009500054 0.00042083 0.0633443 81 0.002910902 60.95025027 5.373334944 62.36066389 5.551338953 0.964141281 0.02261704 070242_06B 0.008040823 0.000105186 0.052525547 0.000813052 51.62552288 1.345215956 51.97741757 1.568036274 0.845223891 0.006770146 070242_07B 0.008124043 0.000136128 0. 053399931 0.001348332 52.15767639 1.740759251 52.82055323 2.597548902 0.663893685 0.0125496 070242_08B 0.00804738 8.954E 05 0.056121084 0.000777407 51.66745896 1.145119974 55.43998579 1.494213886 0.803350035 0.068047038 070242_09B 0.008064495 9.89187E 05 0.051656349 0.002175714 51.7768989 1.265035889 51.13858965 4.196786561 0.291805585 0.012481949 070242_10B 0.008269964 6.97154E 05 0.064284521 0.002202595 53.09066529 0.89139738 63.25795734 4.198224695 0.246516823 0.16072748 070242_11B 0.006238324 6.232 64E 05 0.033800262 0.001084761 40.08860891 0.798531216 33.75123098 2.129646923 0.311750109 0.187767312 070242_11C 0.008226867 9.70382E 05 0.058692499 0.001023688 52.81513093 1.240788212 57.90908241 1.962571914 0.676461233 0.087964638 070242_12B 0.008312 481 0.000125616 0.056841502 0.002311239 53.36248423 1.606037092 56.13234354 4.436069648 0.372196961 0.049345157 070242_13B 0.009724122 0.000202166 0.063654045 0.002134537 62.38088627 2.581044845 62.65630289 4.071043399 0.620364042 0.004395673 070242_13C 0.008500734 0.000398514 0.061869071 0.033763695 54.56588894 5.093488602 64.84491449 74.43194693 0.093782072 1.841482935 070242_14B 0.008148378 0.000112697 0.053158507 0.000927382 52.31327874 1.441115179 52.58782724 1.787357849 0.792940784 0.005220761 300339 1_01 0.008516699 0.000159829 0.057750976 0.001150086 54.66793429 2.043016006 57.00571974 2.206727421 0.942447872 0.041009665 300339 1_02 0.007979151 0.00011288 0.064760725 0.001450724 51.23113251 1.443696851 63.7121563 2.764871799 0.63 1772937 0.195897055 300339 1_03 0.009635281 0.000147092 0.072636385 0.001674002 61.81369231 1.878136628 71.19456722 3.166668143 0.66265452 0.131763915 300339 1_05 0.010157543 0.000463229 0.094657631 0.006775835 65.14730962 5.910729159 91.82825545 12.5308 8352 0.637887796 0.290552681 300339 1_06 0.007665006 0.000165065 0.069191024 0.003458114 49.22181004 2.111727018 67.92802331 6.557231317 0.431530817 0.275382859 300339 1_07 0.007905925 0.000142901 0.056505019 0.002582825 50.76282613 1.827752418 55.809025 1 4.958278521 0.396042125 0.090419049 300339 1_08 0.007357089 0.000146364 0.05927182 0.002299374 47.25170901 1.873066624 58.46452422 4.403207634 0.51330482 0.19178836 300339 1_09 0.007791693 0.000161099 0.056712716 0.001782962 50.0321949 2.060736267 56.0 0860824 3.423394588 0.658001426 0.106705264 300339 1_10 0.007411675 0.000126131 0.051534851 0.001020265 47.60100113 1.614062878 51.02128138 1.969321177 0.859738163 0.067036345 300339 1_11 0.009066108 0.000122429 0.065206049 0.003322686 58.17867252 1.5641 23415 64.13671858 6.324366878 0.265721428 0.092896023

PAGE 109

109 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300339 1_12 0.007069518 0.000117641 0.042716628 0.001539955 45 .41124203 1.505942445 42.47075825 2.996809248 0.462055535 0.06923549 300339 1_13 0.009103215 0.000138369 0.064647979 0.002540883 58.41571946 1.767701857 63.60463833 4.840595047 0.387262524 0.081580825 300339 1_14 0.007287938 0.000109904 0.050680797 0.00 5123607 46.80919072 1.406597958 50.19629637 9.878388504 0.150617673 0.067477202 300339 1_15 0.007626437 9.26787E 05 0.054986507 0.006314904 48.97507292 1.185753671 54.3486415 12.11884341 0.107471121 0.098872178 300339 1_16 0.007012692 0.00010553 0.050864 59 0.002809186 45.04749403 1.350994009 50.37388985 5.421155072 0.273245829 0.105737235 300339 1_17 0.00726354 9.40271E 05 0.041746732 0.003154868 46.6530498 1.20343866 41.52589548 6.140448518 0.17237525 0.123468844 300339 1_18 0.007286545 0.000140177 0. 050607246 0.001588474 46.80027229 1.794023713 50.12521758 3.067958792 0.613257479 0.066332785 300339 1_19 0.00732827 0.000134127 0.050827564 0.001172028 47.06728751 1.716528062 50.3381157 2.263613742 0.793940111 0.064977168 300339 1_20 0.007124659 0.0001 23763 0.046741894 0.0009727 45.76418579 1.5842192 46.38276163 1.886146199 0.834912264 0.013336331 300339 1_21 0.008176481 0.000171705 0.047021852 0.002805609 52.4929695 2.195547305 46.65428223 5.434104306 0.352765722 0.125147939 300339 1_22 0.007462577 0.000152595 0.05130965 0.001849658 47.92670176 1.95259612 50.8038106 3.569577543 0.567660065 0.056631753 300339 1_23 0.009197598 0.00015254 0.067517875 0.003345576 59.01861265 1.948532685 66.33791344 6.354098325 0.335377273 0.1103336 300339 1_24 0.009167 733 0.000122586 0.062532039 0.001700994 58.82785204 1.565977798 61.58470477 3.248263267 0.491906247 0.044765218 300339 1_25 0.007605754 0.000128387 0.061468886 0.005149981 48.84275444 1.642615645 60.56827175 9.828445089 0.202667845 0.193591743 300339 1_2 6 0.007183034 8.22361E 05 0.045631051 0.001134449 46.13781084 1.052617939 45.30468083 2.201957772 0.460820607 0.018389491 300339 1_27 0.009047147 0.000138293 0.059071894 0.002229389 58.05754358 1.76682146 58.27287364 4.270135369 0.405526443 0.003695202 300339 1_28 0.007306859 0.000107936 0.052682666 0.001682811 46.9302748 1.381382436 52.12897343 3.243610951 0.462862519 0.099727623 300339 1_29 0.008885808 0.000164304 0.058277821 0.002357535 57.02676158 2.099445082 57.5113109 4.518694891 0.457605588 0.008 425287 300339 1_30 0.007406965 0.000154582 0.045774614 0.002345648 47.57086222 1.978131348 45.44407386 4.549629572 0.407946961 0.046800126 300339 1_31 0.007253644 9.01016E 05 0.050739235 0.004620437 46.58971629 1.15320993 50.2527664 8.909899608 0.137715 332 0.072892507 300339 1_32 0.007263068 0.000107874 0.046038951 0.001492597 46.65002756 1.380654506 45.70068315 2.895495429 0.458538399 0.02077309 300339 1_33 0.007623446 0.000138521 0.059238487 0.002529055 48.95593934 1.772235864 58.43257301 4.84266531 3 0.426168107 0.162180667 300339 1_34 0.00753777 9.64298E 05 0.057517441 0.001706871 48.40780605 1.233852563 56.78152507 3.274921164 0.431477426 0.147472598 300339 1_35 0.0076908 8.31869E 05 0.049982317 0.000994654 49.38681298 1.06425105 49.52109181 1.92 2748404 0.543777563 0.002711548 300339 1_36 0.00733676 0.000122005 0.050597885 0.001391236 47.12161802 1.56138706 50.11617073 2.687291689 0.605107438 0.059752225 300339 1_37 0.007211498 0.000129938 0.049337158 0.001852634 46.31998773 1.663108137 48.89703 232 3.582030053 0.480315077 0.052703497 300339 1_38 0.006994662 8.96741E 05 0.046735529 0.003126623 44.93207735 1.148034254 46.37658721 6.056595687 0.192585932 0.031147394 300339 1_39 0.007369985 0.000124062 0.05472304 0.001764956 47.33423212 1.587657218 54.0950465 3.39523866 0.522323658 0.124980286

PAGE 110

110 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300339 1_40 0.009214654 0.000138523 0.06724717 0.0025787 59.12755606 1.769467722 66.08040929 4.900602914 0.39253853 0.105218072 300339 1_41 0.007891335 9.70171E 05 0.05787039 0.001318039 50.66950916 1.240931196 57.12033808 2.528501524 0.540069252 0.112934012 300339 1_42 0.007217699 0.000125896 0.048449098 0.002396127 46.3 5967507 1.611372612 48.03738728 4.635584671 0.353357957 0.034925134 300339 1_43 0.007707637 0.000140645 0.052441664 0.002655189 49.49452031 1.799263775 51.89649628 5.116676588 0.361085218 0.046283972 300339 1_44 0.007419402 0.000130181 0.050741922 0.0011 31339 47.65044846 1.665881151 50.25536337 2.185249003 0.787160677 0.05183357 300339 1_45 0.008229121 9.75997E 05 0.124941697 0.008062732 52.82953969 1.247965682 119.5362057 14.50234964 0.184709248 0.558045704 300339 1_46 0.007762706 0.000253886 0.0681170 89 0.007718854 49.84678351 3.247576041 66.90767476 14.62201726 0.290193809 0.254991543 300339 1_47 0.00713917 9.18668E 05 0.048301192 0.002011539 45.85706872 1.175934911 47.89414355 3.892815915 0.309561254 0.042532859 300339 1_48 0.007050091 5.62088E 05 0.05554144 0.00402176 45.28688858 0.719573952 54.88257568 7.722407119 0.111149689 0.17484032 300339 1_49 0.00710535 7.44703E 05 0.042690505 0.005109971 45.64059492 0.953293442 42.44532048 9.927475872 0.089290214 0.075279781 300339 1_50 0.007150626 6.170 92E 05 0.053272651 0.001458867 45.93039319 0.789907778 52.69786543 2.81068433 0.315510383 0.128420234 300339 1_51 0.007423829 8.65195E 05 0.049742936 0.004012661 47.67877497 1.107177221 49.28958373 7.747447804 0.145629901 0.03268051 300339 1_52 0.0068064 8.54555E 05 0.038876885 0.002310524 43.7268148 1.094232889 38.72495837 4.511300834 0.212095668 0.129163636 300339 1_53 0.006923961 7.41137E 05 0.054284032 0.00382244 44.47947273 0.948898744 53.67234637 7.349111437 0.153020323 0.171277655 300339 1_54 0. 008698699 0.000110064 0.049189999 0.001878667 55.83113155 1.406673845 48.75463169 3.632829095 0.331819236 0.145145181 300339 1_55 0.007503154 0.000177226 0.032305412 0.007180891 48.18632822 2.267649621 32.28202383 14.07673162 0.109466728 0.492667513 30 0339 1_56 0.007407171 7.50803E 05 0.050192925 0.000721933 47.57217966 0.960813288 49.72472846 1.395456456 0.704872569 0.043289302 300339 1_57 0.006386954 0.000116825 0.045682662 0.008916782 41.04069932 1.496513932 45.35479431 17.24253019 0.096527776 0.095 11883 300339 1_58 0.007750142 0.00014882 0.048210114 0.002501821 49.7664178 1.90375159 47.80592544 4.840920123 0.370725926 0.041009401 300339 1_59 0.009072582 0.00013633 0.057881015 0.001541007 58.22002793 1.741702197 57.13053564 2.955898989 0.564725192 0.019070227 300339 1_60 0.008964901 0.000118333 0.066437287 0.001614506 57.53210358 1.511954334 65.30963043 3.071946654 0.54346203 0.119086983 300339 1_61 0.007817133 0.000118622 0.052872268 0.003036811 50.19491898 1.517373459 52.31183157 5.848632633 0 .265000499 0.040467185 300339 1_62 0.007262454 0.000117886 0.049195984 0.00112298 46.64609627 1.50878308 48.76042351 2.172305067 0.711339861 0.043361544 300339 1_63 0.007112996 9.37871E 05 0.047914892 0.000936271 45.68953809 1.200546684 47.51992333 1.813 508591 0.67498492 0.03851827 300339 1_64 0.006993811 0.000141907 0.048419538 0.001092364 44.92662503 1.816686898 48.00876055 2.114677041 0.899521675 0.06419944 300339 1_65 0.00898643 0.00016239 0.063474385 0.003107534 57.66964952 2.074782987 62.48479032 5.925062951 0.369768314 0.077061006 300339 1_66 0.008854952 0.000144055 0.065828885 0.003577342 56.82960737 1.840783481 64.73021805 6.804294118 0.300114758 0.122054442 300339 1_67 0.008801955 0.000146 0.059643504 0.002133256 56.49096823 1.865738156 58.82 072731 4.083986415 0.464221107 0.039607791

PAGE 111

111 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300339 1_68 0.00724207 0.000189363 0.048685524 0.002257141 46.51564663 2. 423562402 48.26631902 4.366006427 0.564547135 0.036271098 300339 1_69 0.008660442 0.000145824 0.060138084 0.001802943 55.58664107 1.863746165 59.29451449 3.450549749 0.561997756 0.062533161 300339 1_70 0.007029309 0.000164475 0.050937634 0.002293701 45.1 5386239 2.105503657 50.44446153 4.427150187 0.52018111 0.104879683 300335b_01 0.00826561 0.000135257 0.055810637 0.000980684 53.06283184 1.729379371 55.14148424 1.885295105 0.931357365 0.037696707 300335b_02 0.003427968 2.49867E 05 0.02649538 4 0.001989542 22.05959815 0.321033818 26.5513862 3.931998624 0.098154706 0.169173391 300335b_03 0.007741851 8.32855E 05 0.05023673 0.002545055 49.71337704 1.065457939 49.76707833 4.914984356 0.213066214 0.001079053 300335b_04 0.003299228 2.93038E 05 0.01 2713512 0.002084101 21.23249846 0.37654911 12.82706202 4.17468273 0.056556343 0.655289296 300335b_05 0.008807914 0.000118087 0.13270615 0.012374983 56.52904097 1.509049033 126.520045 22.06498151 0.145110901 0.55320091 300335b_06 0.003370727 2.94728E 05 0.026170692 0.001996298 21.69186215 0.378693346 26.2301747 3.946585898 0.115726124 0.17301877 300335b_07 0.008064013 0.000103158 0.055258892 0.000926929 51.77381929 1.319249211 54.61075445 1.782930932 0.76277625 0.051948287 300335_01 0.096525988 0.001599 433 0.809301528 0.013789638 593.9985111 18.79164951 602.0315513 15.41807026 0.972534684 0.013343221 300335_02 0.084637661 0.000529335 0.753766029 0.012052351 523.7283426 6.290340274 570.3782031 13.90752773 0.391352956 0.081787593 300335_03 0.003358626 3. 00082E 05 0.024843945 0.002559011 21.6141188 0.385576947 24.91659228 5.064198194 0.088229544 0.132541137 300335_04 0.09283443 0.0005618 1.021126516 0.018226716 572.2601391 6.625971958 714.4431285 18.23063691 0.339277682 0.199012327 300335_05 0.072563958 0.004516689 0.585948897 0.03789017 451.5696776 54.17742424 468.2535294 47.94443861 0.962823535 0.035629954 300335_06 0.105366358 0.00171044 0.848775887 0.014532005 645.7604985 19.93425482 623.9453114 15.89929403 0.948220834 0.0349633 300335_07 0.0216100 32 0.001526598 0.677409273 0.078682328 137.8188979 19.25082604 525.1807326 93.08590656 0.609530514 0.737578153 300335_08 0.003569669 7.39551E 05 0.014095539 0.005349509 22.96985199 0.950032787 14.21171761 10.68390387 0.060083675 0.616261498 300335_09 0. 008233376 9.20927E 05 0.059585635 0.004453191 52.85674533 1.177547492 58.76527697 8.516517918 0.150735635 0.100544606 300335_10 0.003602828 5.28797E 05 0.028687116 0.002843467 23.18283861 0.679281762 28.7169708 5.605356285 0.149497296 0.192712951 300335_ 11 0.168453526 0.002846102 1.663724086 0.028689089 1003.552518 31.36496499 994.745838 21.75389663 0.979844204 0.008853196 300335_12 0.085451531 0.003876196 0.702288105 0.032108969 528.5635154 45.95737302 540.1292415 37.94609655 0.99222677 0.021412886 30 0335_13 0.092844444 0.001157481 0.743385295 0.00967064 572.3192075 13.64770717 564.3504872 11.23305645 0.958387134 0.014120162 300335_14 0.105122157 0.001066514 0.88570873 0.009858934 644.336224 12.43601048 644.0285659 10.58913212 0.911517447 0.00047770 9 300335_15 0.003620649 2.83682E 05 0.029315017 0.000849026 23.29729745 0.364410131 29.33653009 1.674292429 0.270934056 0.205860496 300335_16 0.003582095 3.63105E 05 0.024878356 0.000439711 23.04966502 0.466451011 24.95068424 0.871043231 0.573731684 0.07 6191066 300335 2_01 0.008082617 7.56552E 05 0.057906286 0.003757494 51.89278292 0.96752165 57.15479009 7.199772483 0.145180731 0.0920659

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112 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s e rror RHO Discordance 300335 2_02 0.008991416 0.000238087 0.12973842 0.012963925 57.70150116 3.041806839 123.8563502 23.16949084 0.266393304 0.534125613 300335 2_03 0.007957712 7.14966E 05 0.05205839 0.001133638 51.09402544 0.914453726 51.5266693 2.186947 843 0.41287272 0.008396503 300335 2_04 0.008101318 6.37669E 05 0.053443895 0.000797644 52.01237008 0.815476606 52.86292747 1.536990375 0.527569848 0.016089865 300335 2_05 0.007973677 0.000114696 0.051140041 0.001482984 51.19612414 1.466930646 50.63999191 2.862908371 0.496403613 0.010982076 300335 2_06 0.008066802 7.96766E 05 0.041459269 0.00587753 51.79165614 1.018963741 41.24568322 11.42793604 0.071722631 0.255686707 300335 2_07 0.008393397 7.20284E 05 0.054532733 0.000592237 53.87976572 0.920857631 53.91183054 1.140122961 0.79027916 0.000594764 300335_01c 0.00379054 4.14724E 05 0.03509395 0.002238853 24.38841242 0.532648606 35.02101257 4.387472085 0.172411503 0.303606303 300335_02c 0.17144781 0.003003699 1.760939237 0.032637892 1020.050462 33.01500 968 1031.141157 23.86429979 0.945337687 0.010755748 300335_02Bc 0.17406388 0.002533943 1.799464074 0.027125143 1034.430041 27.79528175 1045.210678 19.58120529 0.965794702 0.01031432 300335_03c 0.003841219 3.34259E 05 0.033176549 0.001993452 24.71385734 0 .429284328 33.13847539 3.914267603 0.145685825 0.254224672 300335_04c 0.008771952 8.36151E 05 0.06249145 0.00097757 56.29924634 1.068581867 61.54591832 1.867499592 0.609521898 0.08524809 300335_05c 0.008891008 0.000132642 0.061889711 0.001527177 57.05998 86 1.694895902 60.97072478 2.918338285 0.604873343 0.064141212 300335_06c 0.008738567 0.000103309 0.059921313 0.001427498 56.08590601 1.320291862 59.08688459 2.733049891 0.49655173 0.05078925 300335_07c 0.003766117 3.10916E 05 0.039540054 0.004776276 24. 23156931 0.399336056 39.37289028 9.308725729 0.070091334 0.38456209 300335_08c 0.003793885 5.90233E 05 0.033217245 0.001460433 24.40989015 0.758054712 33.17846793 2.868277791 0.354448046 0.264285192 300335_09c 0.003793885 5.90233E 05 0.033217245 0.001460 433 24.40989015 0.758054712 33.17846793 2.868277791 0.354448046 0.264285192 300335_2_01d 0.008360174 0.000110632 0.064894359 0.004874413 53.66738526 1.414408966 63.83957864 9.273881604 0.177249364 0.15933992 300335_2_02d 0.003823925 5.38243E 05 0.0351288 68 0.002692313 24.60280095 0.691263443 35.05526314 5.274786067 0.184749572 0.298170981 300335_2_03d 0.008013982 5.83334E 05 0.056276064 0.00113649 51.45388182 0.746058023 55.58896926 2.183697194 0.360708523 0.074386834 300335_2_04d 0.003690879 3.17182E 0 5 0.030692897 0.001213726 23.74837137 0.407413643 30.69478287 2.389866802 0.217877701 0.226305934 300335_2_05d 0.008161047 6.92542E 05 0.057900026 0.002664411 52.39428594 0.885595172 57.14878191 5.107967156 0.185062995 0.083195054 300335_2_06d 0.00347159 9 2.88899E 05 0.022375248 0.000280179 22.33988749 0.371166515 22.46785909 0.556421833 0.66471698 0.005695763 070287_01 0.006652832 0.000122234 0.045638055 0.007867378 42.74350502 1.565379716 45.311481 15.22151067 0.109066862 0.056673848 07028 7_02 0.006824557 8.66929E 05 0.061933531 0.00733796 43.84306561 1.110056678 61.0126234 13.98362234 0.108924209 0.281409925 070287_03 0.006995396 6.4351E 05 0.073824703 0.006468526 44.93677443 0.823849893 72.31877708 12.19565137 0.106251602 0.378629227 07 0287_04 0.006523214 7.60839E 05 0.037186531 0.004830888 41.91342466 0.974510491 37.07156959 9.436230417 0.091658365 0.13060831 070287_05 0.006488122 8.43354E 05 0.03605179 0.008334369 41.68867922 1.080232046 35.96013065 16.27002198 0.059574048 0.1593027 74

PAGE 113

113 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 070287_06 0.00687523 0.000105523 0.057464435 0.005149011 44.16749481 1.351091802 56.73063273 9.863720099 0.172572 109 0.221452456 070287_07 0.006972282 0.0001161 0.01390789 0.008200056 44.78881129 1.486361811 14.0238222 16.35708439 0.036788262 2.193766338 070287_08 0.006617957 7.61715E 05 0.031793096 0.005317724 42.52017056 0.975540853 31.77800679 10.43888969 0.071 2336 0.338037683 070287_09 0.006913494 0.000164796 0.036838226 0.010383067 44.41246396 2.109859503 36.73054629 20.23424392 0.088642857 0.209142484 070287_10 0.006710973 0.000120156 0.033655773 0.007198385 43.11580405 1.538677992 33.60931283 14.0925361 0.086801489 0.282852888 070287_11 0.007073066 0.000143635 0.047601625 0.012134856 45.43395272 1.838663447 47.21635194 23.38692191 0.083344242 0.037749617 070287_12 0.007235873 0.000112071 0.063046416 0.010102172 46.4759842 1.434402146 62.0761128 19.2063 5527 0.098972586 0.251306467 070287_13 0.007787935 0.000146145 0.018667516 0.00592033 50.00815969 1.869466001 18.77897869 11.7677202 0.063760481 1.662986124 070287_14 0.007674135 9.98633E 05 0.053047394 0.002718449 49.28021059 1.277610139 52.48069965 5. 235416016 0.25465177 0.060984116 070287_15 0.007637266 0.000139716 0.059248186 0.009045646 49.04434912 1.787496625 58.44187055 17.26759644 0.122021511 0.160801175 070287_16 0.006541023 7.40416E 05 0.034495279 0.007001765 42.02748317 0.948337169 34.433601 95 13.6978151 0.05870662 0.22053694 070287_17 0.006787122 0.000101267 0.039473315 0.004824872 43.60338851 1.296710949 39.30770371 9.403820775 0.123826825 0.109283535 070287_18 0.007180243 0.000103648 0.045192167 0.005488851 46.11995024 1.326676896 44.8 7842446 10.6361706 0.120599787 0.027664202 070287_19 0.006810074 0.000137137 0.075061966 0.019711422 43.75033658 1.75594888 73.48797119 36.8952939 0.080480293 0.404659894 070287_20 0.00750323 0.000145985 0.072071407 0.008934694 48.18681298 1.867951269 7 0.65963166 16.85351062 0.158719047 0.318043247 070287_01B 0.007046071 0.000128014 0.045957633 0.005169506 45.26115877 1.638761008 45.6217493 10.01156161 0.163127183 0.007903917 070287_02B 0.007051229 0.00011068 0.057871011 0.004086909 45.29417281 1.41686 2455 57.12093471 7.830013583 0.223262991 0.207047766 070287_03B 0.007445873 0.000161308 0.056476907 0.002900931 47.81982245 2.064114611 55.78200783 5.568261734 0.422443608 0.142737519 070287_04B 0.007332237 0.000139251 0.054214505 0.003029275 47.09267805 1.782088507 53.60538576 5.826721944 0.340651737 0.121493533 070287_05B 0.007354591 9.72468E 05 0.041860537 0.00432128 47.23572106 1.244532004 41.63680816 8.405074365 0.129572825 0.134470272 070287_06B 0.007301314 0.000216563 0.066956833 0.012410887 46. 89479065 2.771480127 65.80415749 23.48443486 0.162672451 0.287358239 070287_07B 0.007803288 0.000150701 0.060132809 0.010263291 50.10635916 1.927717662 59.28946225 19.56457555 0.115611435 0.154885923 070287_08B 0.008079736 0.000161948 0.050271305 0.00302 6627 51.87435877 2.070998547 49.80050422 5.843462498 0.33374279 0.041643244 070287_09B 0.00706812 0.00012804 0.050317127 0.002082713 45.40229622 1.639052104 49.8448009 4.022690576 0.438190164 0.089126741 070287_10B 0.008767111 0.000755561 0.179251449 0. 040277519 56.26831073 9.652733745 167.4077283 68.19945291 0.386546405 0.663884629 070287_11B 0.007243444 0.000114168 0.048757661 0.003663136 46.52443806 1.461238578 48.33616005 7.080409045 0.210858049 0.037481711 070287_12B 0.009422494 0.00053103 0.22815 0072 0.037253301 60.45496651 6.78056717 208.6597936 60.68009452 0.34737105 0.71027017 070287_13B 0.00742754 0.000139357 0.067920313 0.005017892 47.70251643 1.783277709 66.72060596 9.519233692 0.254994155 0.28504072

PAGE 114

114 Table C Continued Grain N ame 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 070287_14B 0.007103525 9.3679E 05 0.045603876 0.002947166 45.62891701 1.19917361 45.2782926 5.715627302 0.204980976 0.007743764 070287_15B 0.007380986 0.0 00161245 0.035234823 0.006303947 47.40463024 2.063445416 35.15918708 12.32799891 0.124679254 0.34828573 070287_16B 0.007187093 0.000139092 0.058442768 0.011731324 46.16379408 1.780308698 57.66955113 22.38317915 0.09930904 0.199511819 070287_17B 0.007220 494 0.000111984 0.056911511 0.005805253 46.37755952 1.433318951 56.19959991 11.12321734 0.153505947 0.174770646 070287_18B 0.007620678 0.00011254 0.103072687 0.012607226 48.93822964 1.439862359 99.60365298 23.07720438 0.122497145 0.508670333 070287_19B 0 .007219931 0.000104479 0.04181846 0.006149461 46.37395598 1.337261968 41.59580259 11.95100009 0.100529261 0.114871047 070287_20B 0.007574744 0.00021676 0.033336784 0.005435775 48.64436304 2.773251947 33.29593086 10.65412076 0.177825521 0.460970208 0702 87_21B 0.007097737 0.000104303 0.051245969 0.005317721 45.59186822 1.335169853 50.74230637 10.2462021 0.143105024 0.101501853 070287_22B 0.007844177 0.000128986 0.064077155 0.010993577 50.36789147 1.649893933 63.06011048 20.87228034 0.098319184 0.20127175 3 070287_23B 0.007067884 0.00012804 0.053363424 0.010404484 45.4007825 1.639048977 52.78536446 19.95924481 0.095728108 0.139898285 070287_24B 0.007392236 0.000161256 0.055182638 0.006637563 47.47661706 2.063560964 54.53738283 12.73375589 0.183072033 0.12 9466531 070287_25B 0.007239953 0.000114164 0.049578394 0.002796539 46.50209659 1.461184079 49.13042312 5.403384803 0.28033829 0.053496924 070287_26B 0.007062242 0.000117173 0.063062664 0.003885147 45.36466948 1.49995577 62.09163111 7.407882043 0.27016758 3 0.269391564 070287_27B 0.007181857 0.000128173 0.044342585 0.00525978 46.13027998 1.640568646 44.05277939 10.20166533 0.152157339 0.047159353 300340_01b 0.009204092 8.27332E 05 0.066334334 0.001148989 59.0600926 1.05685931 65.21160617 2.18 6888018 0.519159642 0.094331576 300340_02b 0.005396519 0.000547647 0.076878804 0.015106824 34.69354999 7.02067751 75.20241725 28.28887259 0.518875419 0.538664431 300340_03b 0.008490112 0.000227051 0.152942957 0.019314367 54.49799102 2.902263405 144.49971 2 33.73633989 0.213556436 0.622850522 300340_04b 0.011183593 0.000121996 0.209718874 0.014722027 71.69160507 1.55533172 193.3069317 24.56358152 0.156399416 0.629130707 300340_05b 0.007922289 0.000250662 0.061404128 0.002540775 50.86747999 3.205836619 60. 50632626 4.855164726 0.765047494 0.159303115 300340_06b 0.008076944 0.000226964 0.084656082 0.016743194 51.85650756 2.902347516 82.50884508 31.10666803 0.144917231 0.371503655 300340_07b 0.009291441 9.54647E 05 0.086424507 0.006577372 59.61800369 1.21938 1761 84.16289483 12.25686457 0.136096779 0.291635538 300340_08b 0.007208487 7.81042E 05 0.051131072 0.000880688 46.3007172 0.999706573 50.6313292 1.700673977 0.62925605 0.08553226 300340_09b 0.009426446 0.000369653 0.049003936 0.050006496 60.48020405 4.7 20353742 48.5745577 94.56612019 0.053206868 0.245100458 300340_10b 0.009157114 0.000115176 0.062468173 0.003690091 58.76002153 1.471336657 61.52367419 7.040538602 0.213760939 0.04492015 300340_11b 0.007192943 8.27463E 05 0.049752929 0.000975795 46.20123 325 1.059136966 49.29924937 1.886719851 0.586776294 0.06284104 300340_12b 0.007714158 0.000167649 0.092153601 0.009193266 49.53623188 2.144680572 89.50302377 17.02168342 0.219260775 0.446541248 300340_13b 0.009231621 5.68431E 05 0.084542351 0.003831703 5 9.23593217 0.726121377 82.40237733 7.161716132 0.136508432 0.281138068

PAGE 115

115 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300340_14b 0.007227007 6.771E 05 0.060604178 0.003388622 46.41924279 0.866652098 59.740811 6.477610536 0.168360629 0.22298941 300340_15b 0.00729242 6.77502E 05 0.068422569 0.00270226 46.83787358 0.867110313 67.19801602 5.129480459 0.235796472 0.302987255 300340_16b 0.006716528 7.20402E 05 0.0577619 15 0.00339138 43.15137361 0.922542593 57.01621979 6.50026486 0.183518937 0.243173718 300340_17b 0.007772882 0.000179498 0.075427058 0.008164635 49.91187464 2.296112204 73.83272009 15.3585517 0.214871386 0.323987054 300340_18b 0.009602715 0.000227305 0.08 2740739 0.003287033 61.60576331 2.902308513 80.71433404 6.155439428 0.596303062 0.236743212 300340_19b 0.013933608 0.000714902 0.444563305 0.040443289 89.19891795 9.086947761 373.4461012 56.0709674 0.565076497 0.761146474 300340_19Bb 0.01046384 0.0002630 41 0.140912172 0.007837464 67.1016122 3.355679593 133.8492168 13.90188702 0.452684938 0.498677588 300340_20b 0.000630511 0.002737471 0.07931804 0.346140342 4.063123184 35.22221587 77.49964208 564.8574196 0.998434822 0.947572362 300340_21b 0.007150143 8.3 8898E 05 0.051969018 0.00097696 45.92730164 1.073818913 51.44041321 1.884994274 0.624324513 0.107174714 300340_22b 0.008891806 9.52462E 05 0.060594006 0.001286577 57.06508374 1.217073286 59.73107359 2.461847592 0.5047547 0.044633215 300340_23b 0.00755249 2 5.87902E 05 0.058171854 0.002754515 48.50199723 0.752243757 57.40963837 5.279127986 0.165069958 0.155159332 300340_24b 0.00673525 0.000155565 0.054070764 0.002625373 43.27125269 1.992034472 53.46693735 5.051481682 0.47631495 0.190691391 300340_25b 0.00 677367 0.000167416 0.072648374 0.004973402 43.51725312 2.143698629 71.20591559 9.393537228 0.361957621 0.388853401 300340_26b 0.007214676 8.27571E 05 0.05534005 0.001963469 46.34032754 1.059252952 54.68883901 3.774556138 0.323785564 0.152654758 300340_27 b 0.009406284 0.000274672 0.093785638 0.011121801 60.35144761 3.507710057 91.01913013 20.54386117 0.247905614 0.336936669 300340_28b 0.007668977 0.000167637 0.087687063 0.008101288 49.24721415 2.144624688 85.3421475 15.06869487 0.237901637 0.422943814 300340_01 0.008527509 9.92988E 05 0.082019765 0.003327542 54.73702735 1.269314535 80.03802182 6.23532807 0.287586733 0.316112191 300340_02 0.011383032 0.000529731 0.161256948 0.019675188 72.96288587 6.750881268 151.7951008 34.11732803 0.38304885 8 0.519333065 300340_03 0.005942233 6.99253E 05 0.039008222 0.002070638 38.1914988 0.89614968 38.85331022 4.042877675 0.222435908 0.017033591 300340_04 0.007001012 0.000210114 0.046425869 0.001425151 44.97272512 2.68976248 46.07617328 2.763724478 0.97776 5474 0.023948346 300340_05 0.006756407 0.000331035 0.155981406 0.024207243 43.4067197 4.238502134 147.171982 42.08470396 0.317841776 0.705061255 300340_06 0.007498408 0.000298134 0.166087572 0.019024804 48.15596463 3.814495007 156.0099395 32.86305676 0.3 48660638 0.691327586 300340_07 0.005713503 6.54975E 05 0.038057345 0.000565652 36.72560563 0.839595874 37.92367607 1.106235505 0.771415516 0.031591622 300340_08 0.007574234 0.000265161 0.095894298 0.012680782 48.64109963 3.392420198 92.9746577 23.3622471 6 0.266587108 0.476834862 300340_09 0.006984829 0.000155269 0.049920065 0.001805821 44.86912792 1.987754255 49.4608926 3.489658974 0.614924787 0.092836268 300340_10 0.00840119 0.000144797 0.05892796 0.001310938 53.92958714 1.85109491 58.13487462 2.512377 25 0.774946636 0.072336743 300340_11 0.027338271 0.009697919 0.993198538 0.423139766 173.8622729 121.1316038 700.3154169 390.9283028 0.836030774 0.751737191

PAGE 116

116 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s err or *207Pb/235U 2 s error RHO Discordance 300340_12 0.006685766 0.000122371 0.050649936 0.001841101 42.95439454 1.567085289 50.16647346 3.555307625 0.503989456 0.143762924 300340_13 0.006804117 0.000177142 0.050448862 0.002659569 43.71219827 2.268158187 4 9.97213957 5.134817531 0.494509538 0.125268627 300340_14 0.007980601 0.000122856 0.064184439 0.00340098 51.24040852 1.57127953 63.16247375 6.479358142 0.291263171 0.188752348 300340_15 0.006659378 8.43154E 05 0.044975122 0.000663602 42.78541835 1.0797921 54 44.66755889 1.289144422 0.858209803 0.042136633 300340_16 0.006341532 0.000242961 0.070471425 0.004905849 40.74975208 3.112241564 69.14319741 9.285038936 0.551195631 0.410646982 300340_17 0.008640339 0.000188586 0.056921636 0.001292006 55.45816217 2.4 10277811 56.20932669 2.480814145 0.961684737 0.013363699 300340_18 0.007192485 0.000232121 0.053331456 0.001980046 46.19830094 2.970890884 52.75455082 3.813645251 0.869514828 0.124278375 300340_19 0.006559927 0.000275991 0.043783129 0.002344408 42.148549 53 3.534519236 43.50871904 4.55589369 0.786203544 0.031261998 300340_20 0.007516499 0.00028714 0.05197221 0.002172818 48.27171282 3.673780279 51.44349474 4.189949133 0.913991674 0.061655646 300340_21 0.006901526 0.000122446 0.047366135 0.001740934 44.335 84635 1.567710358 46.98808999 3.372570487 0.483175761 0.056445019 300340_22 0.006111854 0.000106894 0.060674425 0.002519233 39.27836126 1.369672368 59.80805753 4.817357646 0.421772984 0.343259706 300340_23 0.00661111 8.21316E 05 0.045922182 0.001151341 4 2.47632548 1.051876924 45.5873355 2.234104646 0.495827987 0.068242857 300340_24 0.006739035 0.00021006 0.047761859 0.001742569 43.2954915 2.68977489 47.3716382 3.374460008 0.854628106 0.086046142 300340_25 0.008035739 0.000122879 0.062452393 0.002636745 51.5930118 1.571481623 61.5085938 5.033361249 0.362757524 0.161206449 300340_26 0.007121078 0.000133437 0.050261125 0.001325205 45.7412678 1.70805206 49.79066246 2.560646554 0.710960058 0.081328395 300340_27 0.006685763 0.000133296 0.043694425 0.00100482 9 42.95437355 1.70698219 43.4224287 1.954104344 0.867128629 0.01077911 300340_28 0.008725558 0.000112345 0.093669443 0.004180541 56.00277182 1.435790301 90.91126409 7.747391631 0.289106727 0.383984236 300340_29 0.006330456 7.65941E 05 0.041556956 0.00109 1061 40.67880208 0.981234102 41.34091431 2.126065282 0.461183221 0.016015907 300340_30 0.007734886 0.000353174 0.09132122 0.008233992 49.66882818 4.517525838 88.72889682 15.26379207 0.507529484 0.440218126 300340_31 0.008203107 0.000144726 0.050895935 0. 003061577 52.66321583 1.850548226 50.40417468 5.90733272 0.294129065 0.044818533 300340_32 0.006867263 0.000210086 0.046706407 0.001530975 44.11648963 2.689765562 46.34833849 2.967998488 0.933472926 0.048153805 300340_33 0.006929257 0.000331057 0.077206 589 0.010228755 44.51337486 4.238061289 75.51142098 19.19144994 0.36240929 0.410508049 300340_34 0.008910277 0.000243466 0.061171539 0.002004434 57.18310307 3.110767652 60.28380916 3.832077277 0.83414427 0.051435139 300340_35 0.005741887 6.87423E 05 0.04 0393463 0.001266786 36.90752888 0.881164425 40.20608339 2.471037271 0.382168788 0.08204118 300340_36 0.008408329 0.000210437 0.058301794 0.001871794 53.97522111 2.690140141 57.53431014 3.588414529 0.779828232 0.061860288 300340_37 0.006728404 0.000122386 0.044128877 0.001191662 43.22742063 1.567206463 43.84498606 2.316270681 0.673867921 0.014085201 300340_38 0.006332866 0.000133188 0.046295524 0.001793974 40.69424013 1.70619663 45.9496934 3.478784816 0.543206903 0.114374066 300340_39 0.009694756 0.00066 1651 0.085629959 0.008330419 62.19340647 8.445600753 83.42006901 15.52250972 0.7025411 0.254455106

PAGE 117

117 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300340_40 0.00613 4853 0.000107993 0.066786591 0.004131753 39.42571332 1.383721275 65.64214064 7.84973499 0.28540085 0.399384101 300340_41 0.009314231 0.00028747 0.104592309 0.007964765 59.76355856 3.671452089 101.0014372 14.58974692 0.406304488 0.408290018 300340_42 0.00 7615919 0.000243191 0.058764165 0.003303079 48.90777939 3.111239185 57.97781085 6.325297804 0.568761582 0.156439702 300340_43 0.006406577 7.55566E 05 0.044048445 0.002877169 41.16638831 0.967868976 43.76677015 5.588365629 0.181487418 0.059414525 300340_4 4 0.007169264 0.000133454 0.055836787 0.004269975 46.04968348 1.708177314 55.16663145 8.195769054 0.244492204 0.165262002 300340_45 0.009050892 0.000199652 0.061913527 0.001538727 58.08146687 2.550650076 60.99349708 2.940327987 0.887741539 0.04774329 300 340_46 0.009096835 0.000155953 0.096603988 0.007149549 58.37496282 1.992331762 93.63196319 13.19637887 0.232687343 0.376548768 300340_47 0.007080625 0.000111617 0.067425813 0.003762364 45.48234086 1.428821736 66.25034776 7.14490989 0.28328098 0.313477704 300340_48 0.008719793 0.000144915 0.066812419 0.002096519 55.9659332 1.852018317 65.66672189 3.986779315 0.530006741 0.147727622 300340_49 0.006422724 9.39549E 05 0.048115661 0.001781955 41.26981576 1.20351845 47.71443142 3.449502929 0.395486576 0.135066 383 300340_50 0.006399033 0.000144154 0.043280428 0.00288788 41.11806919 1.846544594 43.01960233 5.613265185 0.338528087 0.044201551 300340_51 0.008418251 0.000144803 0.059573673 0.002507663 54.03864791 1.851142981 58.75381487 4.800234198 0.40919717 0.08 025295 300340_52 0.008057577 0.000188424 0.152884373 0.008709094 51.73266084 2.409602531 144.448119 15.28234018 0.41126218 0.64185992 300340_53 0.007962134 0.000397224 0.205463612 0.036651306 51.12230537 5.079716716 189.7291436 60.82094133 0.282154866 0. 730551119 300340_54 0.007477902 0.00013356 0.062507718 0.003487063 48.02476251 1.709011767 61.56146407 6.653557079 0.320927879 0.219889208 300340_55 0.006875518 0.000166195 0.057977826 0.003134831 44.16933821 2.127848909 57.22344873 6.00804038 0.44775573 8 0.228125197 300340_56 0.008365927 0.000112173 0.060946775 0.001482713 53.70416143 1.434108787 60.06873117 2.835945823 0.551444479 0.105954789 300340_57 0.008340656 0.000166615 0.063780619 0.002358277 53.54260935 2.130124456 62.77711924 4.496758764 0.54 0717189 0.147099931 300340_58 0.008574739 0.000123107 0.094164268 0.004436064 55.03890268 1.573557465 91.37054189 8.216261592 0.305405314 0.397629679 300340_59 0.006636742 0.000106001 0.042513611 0.001615696 42.64046579 1.357528416 42.27305418 3.14470236 5 0.42076551 0.00869139 300340_60 0.00690467 0.000155247 0.049175365 0.001311224 44.35597089 1.987624793 48.74046966 2.536269619 0.843445084 0.089956022 300340_61 0.008237876 0.000155654 0.057900107 0.002367727 52.88551432 1.9902 57.14886038 4.539827094 0.46257852 0.074600719 300340_62 0.007282853 0.000155355 0.052717143 0.002170532 46.77664782 1.988264135 52.16222667 4.18258769 0.518604953 0.103246721 300340_63 0.008288534 0.00015567 0.059941465 0.002149564 53.20939095 1.99031549 59.10618835 4.1140189 1 0.524170448 0.099766159 300340_64 0.00833239 0.000155685 0.056200332 0.001138758 53.48976671 1.990416512 55.51616997 2.188210404 0.922227923 0.036501136 300340_65 0.006903592 0.000111548 0.045753813 0.000915768 44.34906926 1.42818279 45.42387797 1.7774 76635 0.807458594 0.023661756 300340_66 0.007049433 0.000199145 0.060722429 0.005542922 45.28268032 2.54923664 59.85400809 10.58382357 0.310733504 0.24344782 300340_67 0.008692316 9.61653E 05 0.090797388 0.006428826 55.79034062 1.229060008 88.24142246 11 .9329763 0.157265773 0.367753385

PAGE 118

118 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300340_68 0.006958454 0.000166217 0.05186018 0.001796561 44.70028678 2.127950592 51 .33536059 3.465382271 0.689895164 0.12924958 300340_69 0.006063869 0.000122168 0.047877578 0.002944411 38.97091026 1.565450043 47.48376872 5.697920118 0.328440146 0.179279334 300340_70 0.006872002 0.000155237 0.054709714 0.002240362 44.14682496 1.9875729 66 54.08221756 4.308858256 0.552140158 0.183709046 300340_71 0.008397349 0.000155707 0.057156644 0.001354035 53.90503173 1.990567913 56.43506245 2.599264804 0.782926745 0.04483083 300340_72 0.009697924 0.001322633 0.076669442 0.011129215 62.21363393 16.8 7710447 75.00500168 20.88262276 0.940263495 0.170540197 300340_73 0.0063167 0.000102611 0.051734775 0.002305267 40.59068879 1.314528757 51.21430308 4.446079674 0.365157321 0.207434518 300340_74 0.006787983 0.000122406 0.04609168 0.001032223 43.60889968 1 .56737772 45.75186288 2.002753413 0.805408004 0.046838818 300340_75 0.00690711 0.000133367 0.049131738 0.001402743 44.37159296 1.707512301 48.69824952 2.713286397 0.676598989 0.088846244 300340_76 0.007415103 0.000188259 0.082286313 0.009554936 47.622938 87 2.409022758 80.28811034 17.84898027 0.220287065 0.406849424 300340_77 0.008362612 0.000562414 0.217846204 0.034543743 53.68296666 7.188739251 200.1054848 56.79722063 0.426205954 0.73172666 300340_78 0.00675744 0.000166165 0.055669091 0.003284447 43.41 3337 2.127709781 55.00535661 6.308085335 0.417559132 0.210743468 300340_79 0.00700974 0.00016623 0.064472677 0.004440424 45.02859846 2.128015106 63.43744275 8.453247044 0.345255109 0.29018894 070287_01 0.034106407 0.006722796 1.99040133 0.502 676923 216.1908005 83.54318426 1112.20185 315.5158204 0.782764732 0.805619097 070287_01Rim 0.005903494 4.54485E 05 0.061399246 0.005036555 37.9432528 0.582489308 60.50165561 9.613119234 0.095035689 0.372855959 070287_02 0.005970088 7.20948E 05 0.05439992 7 0.003610195 38.37000009 0.923927154 53.78395304 6.940979359 0.182912628 0.286590183 070287_04 0.006022428 8.94407E 05 0.036265107 0.002116123 38.70537974 1.146151982 36.16916017 4.142522761 0.255332081 0.070121052 070287_05 0.006383749 0.00014415 0.05 17332 0.003052719 41.02016955 1.846518233 51.21278295 5.885583802 0.383457278 0.199024791 070287_06 0.006132065 0.000100362 0.049624948 0.003128657 39.40785676 1.285956416 49.17545776 6.043871008 0.260482456 0.198627556 070287_07 0.006452067 8.3133E 05 0 .054668777 0.002198806 41.45775713 1.064870004 54.04280838 4.229180925 0.320904235 0.232871896 070287_08 0.006066853 7.10685E 05 0.046567509 0.003038397 38.99003043 0.910687253 46.21359524 5.886884035 0.180467112 0.15630822 070287_10 0.00618282 6.04227E 05 0.03970092 0.003279112 39.73302753 0.774184703 39.52999806 6.39442846 0.119509374 0.005136086 070287_11 0.006287978 6.58265E 05 0.046109213 0.002608881 40.40670017 0.843332008 45.76888055 5.057945176 0.185828328 0.117157779 070287_12 0.006426111 0.00 0155118 0.064867093 0.004639965 41.2915073 1.986919777 63.81358143 8.829023668 0.338436738 0.352935435 070287_13 0.006446091 0.000144167 0.048826329 0.003462624 41.41947989 1.846626558 48.4026365 6.693045056 0.316344513 0.144272236 070287_14 0.006799473 0.000177141 0.058526585 0.003472455 43.68246227 2.268154339 57.74995088 6.650607212 0.439870253 0.243593084 070287_15 0.00677834 0.000122403 0.052728346 0.00167863 43.54715675 1.567349848 52.17303165 3.235419463 0.567608229 0.165332062 070287_16 0.006081 035 9.70759E 05 0.047087244 0.002889106 39.08089852 1.243918376 46.71769293 5.595256439 0.261039049 0.163466857

PAGE 119

119 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 0702 87_17 0.006601758 0.000188069 0.048195177 0.006979393 42.41643726 2.408537724 47.79145698 13.47632577 0.19877613 0.112468212 070287_18 0.006279423 0.000122236 0.048757065 0.001860934 40.35189621 1.565988785 48.33558294 3.60005246 0.510494969 0.165172038 070287_19 0.006215189 8.95233E 05 0.04924409 0.002028919 39.94039896 1.146990827 48.80697554 3.922893136 0.350159416 0.181666175 070287_20 0.006404413 0.000144156 0.050393948 0.002358538 41.15253092 1.846553904 49.91906055 4.554506376 0.481531331 0.175614 876 070287_21 0.00642004 0.000122165 0.050856117 0.001904614 41.25262379 1.564864908 50.36570345 3.677124168 0.508564847 0.180938199 070287_22 0.006541924 8.78365E 05 0.063491326 0.002912926 42.03325563 1.125014902 62.50096416 5.554427846 0.29329002 0.32 7478285 070287_23 0.006413539 0.000111363 0.046351539 0.003268271 41.21098557 1.426515648 46.00404966 6.332874382 0.247249396 0.104187873 070287_24 0.006622965 0.000122269 0.057990319 0.004856858 42.55224602 1.565875742 57.2354382 9.300721885 0.22161104 0.256540225 070287_25 0.006404138 0.000154689 0.046444096 0.003253777 41.1507709 1.981473747 46.09385911 6.304278037 0.345733232 0.107239626 070287_26 0.006983212 0.00010632 0.046761522 0.002369216 44.85877716 1.361147457 46.40180092 4.590962463 0.301201 018 0.033253532 070287_27 0.006940103 0.00011059 0.048111854 0.000961364 44.58281047 1.415865399 47.71074298 1.861739624 0.797643426 0.06556034 070287_28 0.0065945 0.00014391 0.050892577 0.003124408 42.36995584 1.843062675 50.40093043 6.02840492 0.356296 581 0.159341792 070287_29 0.006770141 0.000154838 0.06536217 0.003874769 43.49466219 1.982661186 64.28551798 7.372212762 0.386591735 0.3234143 070287_30 0.008190191 0.000428123 0.212360302 0.031339107 52.58063176 5.473538426 195.5214966 51.82497684 0.356 209925 0.731074932 070242_01 0.007226093 5.81605E 05 0.049611083 0.001074159 46.41339729 0.744428625 49.16204511 2.077093403 0.372027653 0.055909957 070242_02 0.007428026 3.92128E 05 0.048993966 0.000400064 47.70562942 0.501809715 48.56490702 0.774303505 0.646588594 0.017693385 070242_03 0.007663199 9.29308E 05 0.05058753 0.000678146 49.21025079 1.188935523 50.10616306 1.310355113 0.904709437 0.017880281 070242_04 0.007491121 9.91768E 05 0.049490477 0.001181207 48.10933768 1.269058952 49.045 37127 2.284236193 0.554989167 0.019085055 070242_05 0.00763577 9.60923E 05 0.053541516 0.001207359 49.03477981 1.229415309 52.95701222 2.325807805 0.558343239 0.074064458 070242_06 0.007581917 8.86326E 05 0.050392652 0.000691972 48.69025299 1.134039621 4 9.91780728 1.337308719 0.851425097 0.024591511 070242_07 0.00802809 6.31633E 05 0.05531323 0.001435053 51.54409865 0.80781654 54.66303548 2.759493943 0.303617404 0.057057513 070242_08 0.007476112 9.0664E 05 0.05294871 0.001392309 48.01330549 1.16015197 5 2.38554536 2.683361785 0.461527426 0.083462715 070242_09 0.007577384 8.02078E 05 0.051441435 0.001055199 48.6612504 1.026254165 50.93107709 2.036897813 0.516285935 0.044566634 070242_10 0.007426945 8.32277E 05 0.052718847 0.001384871 47.69870968 1.065051 974 52.16387034 2.669619473 0.42693821 0.085598723 070242_11 0.010408247 0.000428584 0.348622525 0.034998625 66.74694699 5.467399471 303.6691233 52.02632624 0.411495495 0.78019844 070242_12 0.007849508 0.000155325 0.123753513 0.029511898 50.40198973 1.98 6761796 118.4632281 52.64082294 0.086422916 0.574534727 070242_13 0.007638918 7.92169E 05 0.055022839 0.001279531 49.05491789 1.01351528 54.38360767 2.461295462 0.446243727 0.097983382

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120 Table C Continued Grain Name 206Pb/238U 1s error *207Pb /235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 070242_14 0.007695606 6.99247E 05 0.056522061 0.001227106 49.41756169 0.894582478 55.82540272 2.3571608 0.418813206 0.114783606 070242_15 0.007551958 7.08083E 05 0.052878611 0.00149932 48.49857941 0.906015637 52.31794849 2.889647758 0.331069865 0.073003036 070242_16 0.008100909 0.000155448 0.068236913 0.003560935 52.00975402 1.987844449 67.02157074 6.757895765 0.368415134 0.223984854 070242_17 0.008100909 0.000155448 0.068236913 0.0035 60935 52.00975402 1.987844449 67.02157074 6.757895765 0.368415134 0.223984854 070242_18 0.00766961 6.98974E 05 0.052209874 0.000808686 49.25126119 0.89425599 51.67285405 1.560085789 0.588565015 0.046863927 070242_19 0.008131502 8.80466E 05 0.054654166 0. 00085012 52.20537154 1.125928245 54.02874226 1.636188128 0.696282944 0.033748162 070242_20 0.007708224 6.89088E 05 0.05159186 0.000680172 49.49827207 0.881574945 51.07632619 1.313012299 0.678223765 0.030895999 070242_21 0.008857524 9.14985E 05 0.06455235 7 0.002625389 56.84604232 1.169226889 63.51344198 5.001837735 0.254562522 0.104976198 070242_22 0.009908994 0.000168002 0.080060657 0.001650499 63.56102783 2.144516067 78.19799306 3.100797155 0.822578856 0.187178272 070242_23 0.009044882 0.000142308 0.06 382361 0.001209365 58.04307676 1.818117108 62.81815072 2.307166289 0.830481302 0.076014239 070242_24 0.009258584 0.00014236 0.062695206 0.00164123 59.40815049 1.818394086 61.74061123 3.133742685 0.587671154 0.037778388 070242_25 0.00880962 8.89601E 05 0. 085609859 0.006150783 56.53994398 1.136844063 83.40127005 11.47273856 0.141581719 0.322073346 070242_26 0.008901044 0.00011556 0.059473959 0.000970627 57.12411282 1.476614526 58.65825968 1.859521606 0.795642581 0.026153978 070242_27 0.00904908 0.00010419 8 0.072850545 0.00331245 58.0698925 1.331245407 71.39726547 6.26005762 0.253881045 0.186665034 070242_28 0.009171968 0.000129611 0.080314591 0.002046388 58.85489963 1.655708156 78.43668021 3.842949039 0.554916003 0.249650808 070242_29 0.009142871 9.53856 E 05 0.061589552 0.000993435 58.66903997 1.218551996 60.68368635 1.899404516 0.646975577 0.033199143 070242_30 0.009310686 0.000111879 0.059981095 0.002463061 59.74092145 1.429003921 59.14414998 4.713145846 0.293190509 0.010090118 070242_31 0.009197899 8.03241E 05 0.065075281 0.001594616 59.02053608 1.02609213 64.01206486 3.038007236 0.356715086 0.077977937 070242_32 0.009338802 0.000155122 0.059011053 0.002270239 59.92048694 1.981235401 58.21454353 4.348544189 0.432263544 0.02930442 070242_33 0.00932 6322 0.000103026 0.062197472 0.001010876 59.84078323 1.315912261 61.2649493 1.931630526 0.679862693 0.023246017 070242_34 0.00909278 0.000124505 0.058325334 0.002006279 58.34906104 1.590605258 57.55689446 3.845905655 0.398523828 0.013763192 070242_35 0. 00951981 0.000155163 0.076645662 0.00285681 61.07640264 1.981410015 74.9825764 5.381097353 0.437772802 0.185458735 070242_36 0.008860703 8.39468E 05 0.058662702 0.001081609 56.86635588 1.072726142 57.88050565 2.073617469 0.514069071 0.017521439 070242_37 0.008829706 0.000128249 0.058403753 0.003817499 56.66829172 1.638865308 57.63212527 7.311110244 0.223137481 0.016723894 070242_38 0.009155318 9.28688E 05 0.06090411 0.002997495 58.74854951 1.186385521 60.02789939 5.729376093 0.206801446 0.021312588 0702 42_39 0.008952509 0.000107966 0.058541642 0.001805014 57.45292586 1.379513538 57.7643937 3.459717071 0.391545162 0.005392039 070242_40 0.008838017 9.52772E 05 0.057265904 0.001200498 56.72139998 1.217534596 56.5399938 2.3044562 0.514504507 0.003208458 0 70242_41 0.009350684 0.000128388 0.062854537 0.001009582 59.9963734 1.639797213 61.89282945 1.927966124 0.854946052 0.030640965

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121 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO D iscordance 070242_42 0.009224268 0.000101727 0.062165859 0.000877469 59.18896845 1.299457199 61.23473155 1.676864659 0.78144163 0.033408542 070242_43 0.010129321 0.000142583 0.078944395 0.003430607 64.96721255 1.81967833 77.14808679 6.446444032 0.3245163 82 0.157889518 070242_44 0.010611157 6.61963E 05 0.070651235 0.000670691 68.04134308 0.844441728 69.31373169 1.27167539 0.657259657 0.018356949 070242_45 0.009737953 0.000155214 0.067423488 0.002245211 62.46918358 1.981633686 66.24813638 4.266796432 0.47 9073458 0.057042402 070242_46 0.009250276 0.0001182 0.064099779 0.001902013 59.35508604 1.509830624 63.08169713 3.62644543 0.431020716 0.059075949 070242_47 0.010695537 0.000168183 0.082359236 0.002679418 68.57954353 2.145166194 80.35651993 5.020765787 0 .483752589 0.146559065 070242_48 0.009582125 0.000155178 0.065531661 0.001345119 61.47429494 1.981472433 64.44703742 2.561876381 0.789147546 0.046126907 070242_49 0.009391779 0.000116974 0.065053407 0.001439016 60.25881588 1.493959199 63.99121271 2.74182 0481 0.563313699 0.058326709 070242_50 0.009410875 0.000167894 0.063889842 0.002085581 60.38076935 2.144194305 62.88136242 3.976884171 0.546919757 0.03976684 070242_51 0.00971885 0.00016796 0.062784044 0.001295246 62.34723055 2.144384991 61.82548628 2.47 3320939 0.837861168 0.008438984 070242_52 0.009509052 0.000193456 0.068342421 0.003060579 61.0077068 2.470378912 67.12184789 5.809110308 0.45486589 0.091090178 070242_53 0.009386431 0.000167888 0.068836193 0.001981437 60.22466256 2.144180317 67.59101073 3.761012189 0.62170628 0.10898414 070242_54 0.009358837 0.000129662 0.062520793 0.001121704 60.04843743 1.656044983 61.5739582 2.142641278 0.772376014 0.024775422 070242_55 0.01107753 0.000206534 0.113538098 0.011405107 71.01543032 2.633276181 109.19120 86 20.69271711 0.187036461 0.349623187 070242_56 0.009789896 0.000180737 0.065062649 0.001313766 62.80078044 2.307335814 64.00002309 2.503299893 0.91440499 0.01873816 070242_57 0.009318332 0.000155117 0.061904656 0.001675514 59.78975419 1.981216281 60.98 501498 3.201533361 0.615339357 0.019599254 070242_58 0.009515403 0.000142423 0.072608267 0.00191259 61.04825962 1.818746904 71.16795108 3.617691945 0.568537242 0.142194503 070242_59 0.009333538 0.000167877 0.064883307 0.00183633 59.88686573 2.144150626 6 3.82904117 3.498744796 0.635835008 0.061761471 070242_60 0.009709891 0.000193493 0.06426073 0.001397788 62.29003505 2.47036788 63.23526033 2.665300489 0.916253087 0.014947757 070242_61 0.010653339 0.00019368 0.110842626 0.005419189 68.31039542 2.47044893 6 106.7304801 9.882400415 0.372511887 0.35997294 070242_62 0.009742223 5.35243E 05 0.077034777 0.003149776 62.49644257 0.683381389 75.34946489 5.929984895 0.134956932 0.170578814 070242_63 0.009649312 0.000155193 0.065301361 0.001272654 61.90327242 1.981 541055 64.22756352 2.424468771 0.825414619 0.036188374 070242_64 0.009691849 0.000206271 0.060344722 0.004439108 62.17484604 2.633532824 59.49239947 8.483576844 0.290338426 0.045088895 070242_65 0.010080723 0.000219125 0.066879404 0.001711616 64.6570716 7 2.796548321 65.73047229 3.255222061 0.849544037 0.016330335 070242_66 0.009792898 0.000155227 0.071885226 0.001544476 62.81994413 1.981692301 70.48328918 2.923869807 0.737970087 0.108725701 070242_67 0.009854799 0.000155242 0.069252929 0.001383071 63.2 1509017 1.981759434 67.98680778 2.624951205 0.788956142 0.070185934 070242_68 0.009584611 0.000142441 0.066229789 0.001215976 61.49016789 1.818845703 65.11205607 2.314538529 0.809604411 0.055625462 070242_69 0.010793287 0.000308828 0.081432721 0.00259037 69.20295953 3.938415427 79.48700917 4.858258074 0.899697704 0.129380257

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122 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 070242_70 0.009739933 0.000180727 0.0668217 04 0.001669991 62.48182489 2.307319998 65.67555933 3.17629157 0.742696745 0.048628964 300349_01 0.006781159 0.00011352 0.049098681 0.001348722 43.56520865 1.453600864 48.66625695 2.608944779 0.609732018 0.104816943 300349_02 0.006576948 0.000 114619 0.049104836 0.001151069 42.25755024 1.467975676 48.67221427 2.226805877 0.743682355 0.131793142 300349_03 0.007622894 9.21847E 05 0.052075824 0.001123762 48.95240299 1.179437486 51.54349436 2.167870368 0.560662323 0.050269998 300349_04 0.007043254 0.000251223 0.04729147 0.001847409 45.24312573 3.215813823 46.91570588 3.578907618 0.91330373 0.035650751 300349_04Rim 0.005398917 6.34162E 05 0.041809067 0.002072133 34.70892009 0.813172003 41.58664791 4.034928165 0.23769727 0.165383078 300349_06 0.007 260762 0.000106808 0.052003816 0.001366743 46.63527396 1.367011749 51.47399901 2.636486598 0.560033428 0.094003286 300349_07 0.005678647 5.786E 05 0.060854758 0.004565512 36.50218694 0.741722031 59.98066674 8.720444131 0.136890133 0.391434125 300349_08 0 .006501563 7.72336E 05 0.04892317 0.00124609 41.77476316 0.989257814 48.49638113 2.410937072 0.466721509 0.138600403 300349_09 0.006361826 0.000160058 0.04624437 0.001822118 40.87974688 2.050319844 45.90005278 3.533485724 0.638962746 0.10937473 300349_10 0.005917406 9.2947E 05 0.039492497 0.000785608 38.03240149 1.191206817 39.32643959 1.534115767 0.789787487 0.032905041 300349_11 0.006044718 5.68479E 05 0.043300279 0.001491063 38.84820726 0.728482666 43.03892203 2.900108431 0.273587729 0.097370347 3003 49_12 0.005730232 0.000125852 0.055009585 0.007288267 36.83282901 1.613187695 54.37085188 13.98008845 0.167662542 0.322562959 300349_13 0.006579846 0.000125975 0.049249673 0.001238917 42.27611083 1.6133997 48.81237861 2.396320095 0.761313793 0.133905947 300349_14 0.00633594 8.84992E 05 0.045966024 0.001344719 40.71393409 1.13373519 45.62989469 2.60899169 0.477829371 0.107735524 300349_15 0.007805054 0.000182988 0.061222285 0.002668412 50.11765906 2.340673918 60.33236128 5.099633633 0.53843492 0.169307184 300349_16 0.008172358 0.000148942 0.058464261 0.001228095 52.46661025 1.904514286 57.69016864 2.354732919 0.867768604 0.090545036 300349_17 0.006892453 0.000114674 0.061778582 0.004102799 44.27776064 1.468217713 60.86446268 7.831526444 0.251455442 0.272 518664 300349_18 0.00793896 0.000160266 0.057415095 0.0017764 50.97410019 2.049775961 56.68325796 3.408540898 0.652813215 0.100720353 300349_19 0.005757265 8.83822E 05 0.057155484 0.006209628 37.00609483 1.132887219 56.43394798 11.89302036 0.142859164 0. 344258267 300349_20 0.007858007 0.000126191 0.0538981 0.001068727 50.45634933 1.614122891 53.30060549 2.058191719 0.810053511 0.053362549 300349_21 0.007330043 0.000137451 0.049228148 0.001218777 47.07863398 1.759055478 48.79154913 2.357436091 0.75764190 6 0.0351068 300349_22 0.008048833 0.000171648 0.063318037 0.001662361 51.67674755 2.195102792 62.33550909 3.17220207 0.812506743 0.170990206 300349_23 0.008142484 0.000171661 0.054887273 0.001909229 52.27559462 2.195065972 54.25313338 3.671952338 0.60647 9867 0.036450222 300349_24 0.008090406 0.000376653 0.065834495 0.005354536 51.94259298 4.816093479 64.73556273 10.17609877 0.57337027 0.197618885 300349_25 0.005906305 9.06777E 05 0.046466138 0.001662634 37.96126451 1.162138095 46.11524516 3.223774268 0. 429535188 0.176817463 300349_26 0.005626889 9.40281E 05 0.043529955 0.003696343 36.17042088 1.205409258 43.26241539 7.180210399 0.197998126 0.163929694

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123 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *2 07Pb/235U 2 s error RHO Discordance 300349_27 0.008014642 0.000160277 0.056378974 0.001765783 51.45810351 2.049764581 55.6878847 3.391506849 0.638858236 0.075955142 300349_28 0.008477669 0.000912591 0.091004384 0.018616418 54.41845769 11.66131932 88.4340 7967 34.35802936 0.52873525 0.384643817 300349_29 0.006388028 0.000125945 0.043802734 0.000976449 41.04757686 1.613333019 43.52778937 1.898742532 0.884588371 0.056979979 300349_30 0.007675709 9.21976E 05 0.056281983 0.001374955 49.29027757 1.179541528 55 .59465831 2.641581364 0.491987937 0.113399038 300349_31 0.005942777 0.000106567 0.047184959 0.002278354 38.19498641 1.365710703 46.81243999 4.413302863 0.372025895 0.184084692 300349_32 0.009176086 0.000217287 0.063737213 0.002167768 58.88120436 2.775579 031 62.7356889 4.134034801 0.696589047 0.061440061 300349_33 0.007859499 0.000228519 0.092732439 0.018846267 50.46589192 2.922853106 90.04100351 34.72409041 0.145980822 0.439523218 300349_34 0.00750133 0.00018295 0.068803668 0.004401561 48.17466176 2.340 898618 67.56011356 8.345530561 0.382098751 0.286936341 300349_35 0.007685909 8.88151E 05 0.050986109 0.000650338 49.35552914 1.136256812 50.49129329 1.25616251 0.906027722 0.022494257 300349_36 0.007148973 0.000126066 0.051999243 0.001618157 45.91981162 1.613661927 51.46958588 3.121111019 0.567044112 0.107826286 300349_37 0.006421957 9.64445E 05 0.043241688 0.000869045 41.26490336 1.235408518 42.98189977 1.690886351 0.747451008 0.039946964 300349_38 0.008163203 0.000126248 0.080110322 0.004464555 52.408 07002 1.614366997 78.24468089 8.376293122 0.278284593 0.330202776 300349_39 0.009588466 0.000399548 0.087650773 0.011797318 61.51478142 5.101207697 85.30827078 21.90720407 0.311448639 0.27891187 300349_40 0.009799707 0.000707369 0.166974541 0.038506225 6 2.8634153 9.028023492 156.7819446 65.92329383 0.316177457 0.599039191 300349_41 0.005895739 9.29429E 05 0.038466381 0.000749419 37.89355342 1.191180269 38.32367918 1.464918023 0.809326812 0.011223499 300349_42 0.006212371 0.000137288 0.058309938 0.004103 822 39.9223451 1.758921191 57.54212322 7.859101054 0.314967659 0.306206604 300349_43 0.005638136 5.3356E 05 0.056033014 0.00395333 36.24251613 0.684012632 55.35531322 7.58772903 0.135144742 0.345274843 300349_44 0.007119848 0.000148782 0.04797248 0.00105 8357 45.73339314 1.904457391 47.57571908 2.049750103 0.947297974 0.03872408 300349_45 0.010971815 0.00094688 0.407792244 0.069196226 70.34139671 12.06943617 347.2664158 97.43629676 0.510711343 0.797442559 300349_46 0.007964973 7.65156E 05 0.072170946 0.0 02268676 51.14046489 0.9786385 70.75389824 4.292271307 0.306035705 0.277206399 300349_47 0.005782014 9.51902E 05 0.046590701 0.002104886 37.16471484 1.220118271 46.23609535 4.079934767 0.365014491 0.196196942 300349_48 0.005851401 8.61345E 05 0.061976626 0.005823862 37.60940974 1.103974331 61.0538258 11.10569715 0.157997172 0.383995855 300349_49 0.006929069 0.00011468 0.051127312 0.001256131 44.5121696 1.468247899 50.62769651 2.425258617 0.673909692 0.120794097 300349_50 0.00839164 0.000433666 0.1438260 57 0.02667108 53.86853535 5.543277764 136.4390628 46.80623146 0.281259963 0.605182459 300349_51 0.006920856 0.000148754 0.046375355 0.001513063 44.45959631 1.904478077 46.02715891 2.934226366 0.65913453 0.03405734 300349_52 0.005980463 7.71089E 05 0.0463 33626 0.001919916 38.43648046 0.98817252 45.98666711 3.722646576 0.31173119 0.16418208 300349_53 0.005824998 8.95287E 05 0.050472624 0.002213804 37.44020184 1.147504739 49.99510751 4.274989722 0.351010893 0.251122686 300349_54 0.008001841 0.000114887 0.0 55789832 0.001295137 51.37623995 1.469325219 55.12147696 2.489486599 0.618735441 0.06794515

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124 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300349_55 0.005994831 0. 000112253 0.05683815 0.00294283 38.52854896 1.438504001 56.12912302 5.646646795 0.362355011 0.313572939 300349_56 0.007887333 0.000114863 0.05347178 0.000876552 50.64391311 1.469192487 52.88980273 1.68893061 0.888488019 0.042463566 300349_57 0.007928909 9.56465E 05 0.055455193 0.000987535 50.90982274 1.223355945 54.79961017 1.899097725 0.677590517 0.070982027 300349_58 0.005644863 6.01003E 05 0.053351881 0.004342289 36.28563322 0.770465581 52.77423868 8.353904487 0.131984178 0.312436633 300349_59 0.0106 57851 0.000718807 0.152417869 0.019094679 68.33917341 9.166177133 144.0371919 33.37081901 0.539881196 0.525544948 300349_60 0.006430113 0.000107785 0.052145631 0.001758708 41.31713796 1.380652625 51.61086167 3.391509995 0.4974315 0.199448786 300349_61 0. 005922491 0.000102023 0.039780834 0.002312346 38.06499338 1.307507511 39.60803606 4.510933825 0.297160551 0.038957818 300349_62 0.008699074 0.000217229 0.065844376 0.002639601 55.83352749 2.776149598 64.7449754 5.022790326 0.623363467 0.13763922 300349_6 3 0.005971528 9.86273E 05 0.039658319 0.003304328 38.37922128 1.263933842 39.48839449 6.443786259 0.199411187 0.028088587 300349_64 0.006479179 8.40058E 05 0.042712251 0.00061387 41.6314005 1.076020423 42.46649635 1.195149175 0.902211722 0.019664816 3003 49_65 0.007658639 0.000160225 0.052365439 0.001267291 49.18107825 2.049829827 51.82295579 2.443916581 0.86464299 0.050978905 300349_66 0.006117258 0.000111137 0.08092092 0.00558849 39.31298587 1.424030321 79.00637785 10.47172352 0.264033549 0.502407439 3 00349_67 0.005976315 8.27635E 05 0.051986593 0.002632695 38.40990016 1.060639215 51.45737666 5.07557631 0.274167988 0.253558913 300349_68 0.005813271 6.23984E 05 0.038683345 0.000822269 37.3650437 0.799791243 38.53578657 1.606928469 0.505233084 0.03038066 6 300349_69 0.006692028 6.37799E 05 0.051506751 0.002431837 42.99449466 0.816784432 50.99414815 4.690924795 0.202533111 0.156873951 300349_70 0.006535689 0.000104401 0.04637872 0.001426326 41.99332242 1.337171203 46.0304242 2.766125977 0.519794351 0.0877 05075 300349_71 0.006041009 8.9571E 05 0.071445791 0.004627958 38.82443623 1.147800905 70.06695406 8.75227185 0.229814029 0.44589519 300349_72 0.006537179 6.48554E 05 0.045731107 0.000898902 42.00286423 0.830684746 45.40183284 1.744791125 0.504971276 0.0 74864128 300349_73 0.008160498 0.000194408 0.058643658 0.001947092 52.39077811 2.485863324 57.86224114 3.731431567 0.717852707 0.094560164 300349_74 0.007735784 0.000112567 0.05219702 0.000901838 49.67457154 1.440042905 51.66045055 1.739735158 0.84235424 7 0.038440993 300349_75 0.007173876 5.61218E 05 0.053172642 0.001870683 46.07919661 0.718371154 52.60145464 3.60373643 0.222861971 0.123993872 300349_76 0.008056657 0.00011037 0.055855166 0.000990573 51.72678129 1.411490321 55.18430526 1.90421633 0.77262 0571 0.062654118 300349_77 0.007025787 0.000171515 0.058583447 0.002881263 45.13131362 2.195630753 57.80449176 5.519571418 0.496982298 0.2192421 300349_78 0.005997487 7.14652E 05 0.051036033 0.00340899 38.54556494 0.91583373 50.53952249 6.575709534 0.179 345623 0.237318379 300349_79 0.008032135 0.000878365 0.100413102 0.06231847 51.56996869 11.22912444 97.15266132 111.8618829 0.185045149 0.469186248 300349_80 0.008236439 0.000171675 0.06271024 0.002709752 52.87632902 2.195030969 61.75497488 5.171295957 0 .4829132 0.143772156 300349_81 0.008429432 9.23922E 05 0.057805654 0.001208568 54.11012007 1.181147003 57.05820374 2.318756244 0.524505311 0.051668007 300349_82 0.008055589 0.000105845 0.056763109 0.001191381 51.71995259 1.35362657 56.05702682 2.28805300 2 0.626260275 0.077368966

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125 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300349_83 0.012217227 0.001140787 0.598248775 0.082085615 78.27756962 14.52179568 476.0975 879 101.7043376 0.68198379 0.835585032 300349_83Rim 0.006342176 6.3674E 05 0.060367272 0.005835581 40.753875 0.815712424 59.51399216 11.14482736 0.105252676 0.315221958 300349_84 0.00702298 9.65683E 05 0.047763432 0.001166931 45.11335006 1.236256788 47.3 7316272 2.260362379 0.563105147 0.047702381 300349_85 0.006030133 7.26021E 05 0.052238438 0.004945602 38.75475318 0.930371667 51.70041656 9.521913119 0.128534223 0.250397661 300349_86 0.006036293 9.18362E 05 0.075173698 0.005741963 38.79421846 1.17683296 5 73.59349017 10.8158966 0.200267046 0.472858015 300349_87 0.006343823 0.000160055 0.052273543 0.001922264 40.76442556 2.050329442 51.73428999 3.706174608 0.686489073 0.212042427 300349_88 0.008636455 0.000946809 0.166994858 0.040968101 55.4333414 12.096 45462 156.799621 70.06495842 0.450048494 0.646470182 300349_89 0.005990708 3.35577E 05 0.075087862 0.00610569 38.50212504 0.430056732 73.51242835 11.50001206 0.070065507 0.476250127 300351_01 0.007356941 3.4185E 05 0.053382261 0.000992622 47. 25076134 0.437500601 52.80352168 1.912630563 0.250152432 0.105158902 300351_02 0.007417634 3.42376E 05 0.054974501 0.001086481 47.63912979 0.438147413 54.33708721 2.090231723 0.23382708 0.123266773 300351_03 0.007375403 4.59054E 05 0.059626821 0.00202856 1 47.36890203 0.587485255 58.80474185 3.883806287 0.183434865 0.194471389 300351_04 0.007773858 9.66004E 05 0.079665476 0.007674093 49.91811321 1.23574545 77.82642744 14.38257941 0.130383913 0.358596882 300351_05 0.008577153 0.000211002 0.165215074 0.023 517915 55.05433222 2.696910184 155.2499569 40.57740317 0.174852836 0.645382625 300351_06 0.007435344 7.57849E 05 0.075175175 0.006944402 47.75245055 0.969802561 73.59488435 13.07358493 0.111668486 0.351144431 300351_07 0.007316981 3.67028E 05 0.056667381 0.000777833 46.99504496 0.469742058 55.96504732 1.494259018 0.365623917 0.160278652 300351_08 0.007252226 4.31764E 05 0.05051107 0.000465788 46.58064387 0.552628124 50.03226588 0.900179234 0.645716993 0.068987921 300351_09 0.007722793 0.000897419 0.0642 58402 0.008153043 49.59146873 11.47611515 63.23303928 15.49716603 0.916599345 0.215734855 300351_10 0.00715264 3.65726E 05 0.051776635 0.000971202 45.94328063 0.468151343 51.25471387 1.874231672 0.2728539 0.10362819 300351_11 0.00728343 2.4458E 05 0.0506 27763 0.00081033 46.78034124 0.313038294 50.14504523 1.565608925 0.210029774 0.067099431 300351_12 0.007465154 3.55458E 05 0.064969189 0.002042622 47.94319442 0.4548673 63.91092295 3.891102608 0.15190059 0.249843498 300351_13 0.007288487 4.58497E 05 0.07 0674099 0.00616646 46.81270173 0.586822367 69.33541414 11.66188658 0.073360153 0.324837065 300351_14 0.007318181 3.1642E 05 0.063982089 0.00112777 47.0027284 0.404971712 62.9693946 2.151266286 0.245548401 0.253562327 300351_15 0.007238264 4.71497E 05 0.0 50207074 0.000808066 46.49128801 0.603491494 49.73840796 1.561862925 0.40494103 0.065283954 300351_16 0.007199116 1.94431E 05 0.050489875 0.000759407 46.24074128 0.248874567 50.01178066 1.467450387 0.179777503 0.075403022 300351_17 0.045086987 0.00033487 5 0.341208206 0.00332546 284.2784934 4.13042542 298.0717375 5.028698451 0.762168882 0.046274914 300351_17B 0.045429273 0.000255128 0.353413811 0.004367525 286.389406 3.145903456 307.2699252 6.542487256 0.454593985 0.067954972 300351_18 0.007160532 5.2471 5E 05 0.058119702 0.003172018 45.99379064 0.671656947 57.3595971 6.078390781 0.135050269 0.19815004

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126 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300351_19 0.0069 7507 3.9039E 05 0.050192452 0.001443073 44.80665975 0.499811138 49.72427186 2.788425379 0.195079632 0.098897619 300351_20 0.007860718 3.21601E 05 0.05304536 0.000581909 50.47369196 0.411380725 52.47873821 1.121826244 0.373095017 0.03820683 300351_21 0.00 7226656 2.90944E 05 0.049216144 0.000468822 46.41699748 0.372400677 48.77993331 0.907159086 0.422766949 0.048440735 300351_22 0.007761763 4.61604E 05 0.062704139 0.002777948 49.8407482 0.590521826 61.74914648 5.301302161 0.134876535 0.192851221 300351_23 0.007179608 4.84507E 05 0.061732099 0.00474434 46.11588335 0.620178652 60.82001216 9.053785419 0.088918406 0.241764648 300351_24 0.007205929 4.57973E 05 0.054313657 0.001859017 46.28434551 0.586199655 53.70087607 3.577410273 0.186172098 0.138108185 3003 51_25 0.007480403 0.000168907 0.157906238 0.014340861 48.04076331 2.161271181 148.8612111 24.99562876 0.249901694 0.677278164 300351_26 0.007132476 3.9153E 05 0.048760423 0.000786808 45.81422202 0.501192184 48.33883395 1.522886988 0.340411455 0.052227407 300351_27 0.007080208 2.89495E 05 0.051078388 0.001204843 45.47966797 0.370600054 50.58043789 2.326400338 0.173678327 0.100844716 300351_28 0.007615898 3.82273E 05 0.060241093 0.001827807 48.90764662 0.489108148 59.39316546 3.497756268 0.165864388 0.1765 44199 300351_29 0.007226948 2.78874E 05 0.050126994 0.000856694 46.4188633 0.356950841 49.6609841 1.65594008 0.22602833 0.06528507 300351_30 0.008722511 8.18028E 05 0.092963927 0.004937782 55.98330278 1.045474144 90.25607187 9.153448643 0.177325154 0.379 728127 300351_31 0.007371679 2.92401E 05 0.052639623 0.001179625 47.34507473 0.374211344 52.08745705 2.274357972 0.177323134 0.091046532 300351_32 0.007113478 3.02109E 05 0.049993077 0.001104926 45.69262149 0.386734669 49.5314964 2.135779453 0.192472522 0.077503714 300351_33 0.007679933 6.63024E 05 0.085220176 0.003200031 49.31730009 0.848255409 83.03674821 5.979084443 0.230441169 0.40607862 300351_34 0.007386139 2.92547E 05 0.056325944 0.001039277 47.43760103 0.374393363 55.63691448 1.996906527 0.21492 3709 0.147371822 300351_35 0.007283993 3.92648E 05 0.051364603 0.000979062 46.78394229 0.502547776 50.85688117 1.890134292 0.283070549 0.080086289 300351_36 0.007510854 3.30647E 05 0.050270175 0.000368438 48.2355965 0.423099117 49.79941181 0.71223714 0.6 00735557 0.031402285 300351_37 0.007334158 4.58789E 05 0.054147213 0.0021333 47.10496864 0.587169756 53.54057395 4.105343761 0.159340856 0.120200529 300351_38 0.00737955 3.93364E 05 0.059696203 0.002266543 47.39543731 0.503415816 58.87122145 4.338667275 0.140938785 0.194930288 300351_39 0.007132119 2.77892E 05 0.049407161 0.000845806 45.81193597 0.355727866 48.96476378 1.636024691 0.227843986 0.064389728 300351_40 0.006701351 0.000104614 0.073835623 0.010356281 43.05419066 1.339675429 72.32910224 19.490 27882 0.113319465 0.404745955 300351_41 0.007380049 3.67535E 05 0.049229221 0.000397608 47.39863324 0.470360839 48.79258702 0.769378156 0.61669755 0.028568966 300351_42 0.00704724 3.52017E 05 0.048499689 0.001135767 45.26863939 0.45065105 48.08637947 2.1 98485127 0.21363359 0.058597468 300351_43 0.007327661 3.41597E 05 0.050263788 0.000925408 47.06339561 0.437190147 49.79323744 1.788468692 0.253462567 0.054823546 300351_44 0.00702487 3.39034E 05 0.047010489 0.000491385 45.12544695 0.43404063 46.64326343 0.952810772 0.461854214 0.032540958 300351_45 0.007127358 3.78473E 05 0.048499247 0.000726827 45.78146504 0.484480776 48.08595074 1.407182016 0.354535176 0.047924303 300351_46 0.007089748 3.14326E 05 0.048487455 0.000428264 45.54073221 0.402382414 48.074 53205 0.829273238 0.502067927 0.052705658

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127 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 300351_47 0.00738882 8.67942E 05 0.078071887 0.005441212 47.45475891 1.110 731489 76.32668874 10.22332386 0.169540745 0.378267816 300351_48 0.007196194 3.15295E 05 0.048454687 0.000649641 46.22203674 0.403580762 48.04279998 1.257844694 0.326979785 0.037898774 300351_49 0.007288367 4.32008E 05 0.053022163 0.001392389 46.8119335 0.552920836 52.45637121 2.683328727 0.226085083 0.107602519 300351B_01 0.058587695 0.0026664 0.42464023 0.019352966 367.0189962 32.43294179 359.3454275 27.39977055 0.998636774 0.021354296 300351B_01B 0.051526718 0.000666981 0.389845285 0.005309999 323.8 775565 8.175037144 334.2394512 7.743504592 0.950401165 0.031001411 300351B_02 0.007606945 8.54899E 05 0.053366292 0.00109569 48.85037338 1.093803736 52.78812912 2.111155969 0.547622784 0.074595478 300351B_03 0.007702142 7.7265E 05 0.052118071 0.000819923 49.45936683 0.988480874 51.58426565 1.581893197 0.637832233 0.041192771 300351B_04 0.007497095 7.03212E 05 0.051081205 0.001011483 48.14756187 0.899832555 50.58315876 1.953221218 0.473944693 0.048150352 300351B_05 0.007460684 8.54381E 05 0.050349515 0.0 00896516 47.91459159 1.093300319 49.87610947 1.732514508 0.643344811 0.039327804 300351B_06 0.007822365 0.000100769 0.062051608 0.003014311 50.22838355 1.289003717 61.12551171 5.755257253 0.2658664 0.178274633 300351B_07 0.007616771 0.000100705 0.0511232 61 0.000903255 48.91323293 1.288457667 50.62378432 1.744246395 0.748495433 0.033789481 300351B_08 0.00760797 5.81148E 05 0.053465 0.001473448 48.85692877 0.743561448 52.88326842 2.838239461 0.277558182 0.076136362 300351B_09 0.007732629 8.41567E 05 0.052 77655 0.001094617 49.65439061 1.076612613 52.21952235 2.110270601 0.52499143 0.049122083 300352_01 0.007158588 0.000126993 0.05157041 0.002032346 45.98135095 1.625509079 51.05561515 3.920828808 0.450658875 0.099386996 300352_02 0.007165364 0.000106126 0. 048089459 0.00091577 46.02471967 1.358414916 47.68904806 1.773520996 0.77793612 0.034899593 300352_03 0.007160837 0.000124208 0.050009382 0.001302373 45.99574648 1.589857847 49.54726346 2.51716026 0.666324248 0.071679377 300352_04 0.007218219 9.92003E 05 0.047698274 0.001031881 46.36300387 1.26970362 47.31001925 1.999021302 0.635509012 0.020017227 300352_05 0.009188846 0.000141404 0.061414321 0.001819716 58.9627123 1.80631711 60.51607623 3.478439969 0.519726218 0.025668616 300352_06 0.007514384 0.000168 913 0.050270978 0.001538761 48.25817855 2.16127575 49.80018763 2.972963995 0.734673845 0.030963921 300352_07 0.007123712 9.91729E 05 0.04865147 0.000967882 45.758125 1.269471717 48.23334801 1.873393182 0.699983724 0.05131767 300352_08 0.006739004 0.00010 0454 0.044980593 0.001274389 43.29529302 1.286361407 44.67287442 2.474953586 0.526481331 0.030837089 300352_09 0.006896005 8.94005E 05 0.052625927 0.003672718 44.30049729 1.144643728 52.0742464 7.072856397 0.186755456 0.149282028 300352_10 0.006935294 0. 000100508 0.047758288 0.001464449 44.55202447 1.286797002 47.36817773 2.83626981 0.47300829 0.05945243 300351B_10 0.007503846 6.62214E 05 0.053909772 0.002083497 48.19075432 0.847367475 53.31184971 4.010499126 0.228889499 0.096059233 060065_0 1 0.005842208 3.96502E 05 0.043049601 0.001482271 37.55049402 0.508208075 42.79493459 2.883713708 0.197600303 0.122548162 060065_02 0.006134216 5.90937E 05 0.040262552 0.000405776 39.42163304 0.757193274 40.07831813 0.791947664 0.955909344 0.016385046 06 0065_03 0.006050781 8.97213E 05 0.078103562 0.005390812 38.88705198 1.149715931 76.35651983 10.12856712 0.215810417 0.490717334

PAGE 128

128 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO D iscordance 060065_04 0.005769953 7.85449E 05 0.058989391 0.007483112 37.08741322 1.006784032 58.19377433 14.2987662 0.109138157 0.36269105 060065_05 0.005746444 5.62683E 05 0.040424027 0.000633215 36.93674073 0.721269615 40.23591036 1.235511723 0.6252822 63 0.08199565 060065_06 0.005797806 6.1836E 05 0.043432435 0.002741926 37.26592762 0.79259486 43.16752619 5.329166549 0.169843657 0.136713847 060065_07 0.005808737 2.86527E 05 0.045733732 0.001551628 37.33598409 0.36726375 45.40438149 3.010803269 0.14587 6253 0.177700855 060065_08 0.005908374 6.88059E 05 0.056132944 0.004001074 37.97452696 0.881833205 55.45138688 7.678466869 0.164399711 0.315174442 060065_09 0.005678977 3.96228E 05 0.038065711 0.000723084 36.50430265 0.507939205 37.93185882 1.414003334 0 .367556005 0.037634754 060065_10 0.008557367 0.00036365 0.377424352 0.038121299 54.92787042 4.647712138 325.1247273 55.43655607 0.422060249 0.831056005 060065_11 0.005715129 3.41146E 05 0.103808646 0.02663867 36.73602764 0.437313079 100.2808457 48.424822 64 0.02698216 0.63366855 060065_12 0.005796966 4.24065E 05 0.038319979 0.000700153 37.26054311 0.543559537 38.1805286 1.36884221 0.400614913 0.024095672 060065_13 0.005878774 5.62841E 05 0.04941771 0.00215405 37.78483783 0.721377117 48.97497016 4.1638970 46 0.220264022 0.228486761 060065_14 0.005935185 3.4158E 05 0.053249934 0.001779762 38.14633415 0.437773431 52.67596631 3.428480811 0.172670483 0.275830387 060065_15 0.005654634 3.4103E 05 0.041850273 0.00273506 36.34826839 0.43719005 41.62680557 5.32390 0829 0.093226278 0.126806204 060065_16 0.00571349 5.34856E 05 0.040288927 0.000869158 36.72551908 0.685623118 40.10406075 1.695903745 0.434214829 0.084244378 060065_17 0.005655412 4.93134E 05 0.037510129 0.001701647 36.35325579 0.632177417 37.38829949 3. 327814107 0.192857178 0.027683626 060065_18 0.00568823 4.37735E 05 0.040951321 0.001535819 36.56361391 0.561142256 40.75035676 2.99383154 0.205725187 0.102741256 060065_19 0.005808303 4.51761E 05 0.03995934 0.000550694 37.33320607 0.579052673 39.78232956 1.07502175 0.564539173 0.061563099 060065_20 0.005764995 3.55002E 05 0.04343887 0.00198901 37.05563986 0.455051624 43.17378872 3.867179261 0.135142843 0.141709798 060067_01 0.005743102 3.8253E 05 0.050241616 0.002080047 36.91531878 0.4903477 24 49.77180234 4.017834846 0.161475264 0.258308579 060067_02 0.005576313 3.40881E 05 0.038080893 0.001235908 35.84621137 0.437033033 37.94670812 2.416209366 0.188816841 0.055353859 060067_03 0.005684929 2.72596E 05 0.040561044 0.002216779 36.54245074 0.3 4945126 40.36961464 4.32145926 0.088526468 0.094803082 060067_04 0.005626447 2.58842E 05 0.039467342 0.001758106 36.16758954 0.331837906 39.30186947 3.431665771 0.103917037 0.079748876 060067_05 0.005657331 2.7253E 05 0.040371695 0.001160156 36.36555266 0.349375802 40.18483917 2.263203567 0.168045477 0.095042971 060067_06 0.005654087 3.41029E 05 0.044073638 0.002125338 36.34476189 0.437188945 43.79126945 4.129457302 0.12577147 0.170045483 060067_07 0.00587357 6.46267E 05 0.0620404 0.007058946 37.7514827 3 0.828301633 61.11479715 13.45232565 0.098346251 0.382285723 060067_08 0.005665174 3.27302E 05 0.044517812 0.003617456 36.41582662 0.419587472 44.22312431 7.020600503 0.072274988 0.176543331 060067_09 0.00615089 9.94926E 05 0.08980591 0.006008381 39.528 46373 1.274795602 87.31811941 11.16481934 0.242710247 0.547305141 060067_10 0.005524067 3.54559E 05 0.038061365 0.001059581 35.5112835 0.454592852 37.92760794 2.071703531 0.230950562 0.063708854

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129 Table C Continued Grain Name 206Pb/238U 1s er ror *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 060067_11 0.005676894 2.72577E 05 0.03845697 0.001075455 36.49094899 0.349429251 38.31447684 2.101923926 0.172096013 0.047593704 060067_12 0.005569418 2.58699E 05 0.038073858 0.000526577 35.80201345 0.331673984 37.93982774 1.02982078 0.336042326 0.056347496 060067_13 0.005693016 3.27358E 05 0.048085912 0.001878651 36.59428747 0.419647398 47.68561223 3.636622682 0.14774158 0.232592689 060067_14 0.005553675 3.54612E 05 0.041760 246 0.002516485 35.70109303 0.454647974 41.53906673 4.899371784 0.106829116 0.140541764 060067_15 0.005669409 3.13584E 05 0.038541335 0.000484336 36.44296984 0.401999737 38.39695998 0.946802464 0.440308905 0.050889189 060067_16 0.005651868 3.27276E 05 0. 038057542 0.000872746 36.33053702 0.419558951 37.92386947 1.706561138 0.252829341 0.042013974 060067_17 0.005652598 3.96185E 05 0.037420617 0.001172338 36.33521801 0.507896659 37.30069727 2.29345725 0.224164268 0.025883679 060067_18 0.005647922 2.18341E 05 0.038799035 0.00055002 36.30524161 0.279909707 38.64886961 1.074903799 0.272899899 0.060638979 060067_19 0.005526515 2.99572E 05 0.038972097 0.001052952 35.52697681 0.384092423 38.81800831 2.056943807 0.201013731 0.08478105 060067_20 0.005680601 2.999 05E 05 0.041439694 0.002041954 36.51471338 0.384460215 41.22659855 3.977628268 0.107852648 0.114292358 060072_01 0.010354252 3.60255E 05 0.078342681 0.001763931 66.40246351 0.459687072 76.5816915 3.319002942 0.154850817 0.132919864 060072_02 0.010412848 5.5395E 05 0.082458688 0.00227087 66.77630422 0.70679553 80.449809 4.255627057 0.193564289 0.169963173 060072_03 0.010753474 5.5579E 05 0.071972778 0.000524456 68.94905052 0.708904787 70.56621828 0.993245746 0.709360764 0.022917025 060072_04 0.013540986 0.000286177 0.123131855 0.004376268 86.70229099 3.639708962 117.9013929 7.897075238 0.595050417 0.2646203 060072_05 0.013730789 6.99879E 05 0.490116673 0.008190555 87.90933689 0.890059964 404.96946 11.13115053 0.305240333 0.78292354 060072_06 0.010442595 4.14466E 05 0.069861662 0.000567547 66.96607585 0.528813121 68.5646788 1.076952928 0.488662249 0.023315255 060072_07 0.01026204 6.97364E 05 0.069900074 0.000680508 65.81411137 0.889906691 68.60113272 1.291188954 0.698124487 0.040626462 06007 2_08 0.011384271 0.000143915 0.076447054 0.001062111 72.97078194 1.834401313 74.79526151 2.002631138 0.90998183 0.024392983 060072_09 0.01060416 4.02119E 05 0.075185476 0.001269234 67.99671177 0.512977829 73.60461241 2.395741657 0.224869796 0.076189527 0 60072_10 0.010298555 8.58472E 05 0.07066144 0.001682368 66.04709456 1.095449221 69.32340904 3.188347566 0.350439058 0.047261301 060072_11 0.01096835 9.49005E 05 0.077021498 0.000846538 70.31930744 1.210165024 75.33694664 1.595473053 0.787311508 0.06660263 6 060072_12 0.01082418 7.87095E 05 0.098819136 0.007135591 69.39997142 1.003849603 95.68087152 13.14423345 0.101745081 0.274672457 060072_13 0.010477843 5.97171E 05 0.069717917 0.000750402 67.19094093 0.761891289 68.42825105 1.424000043 0.529646194 0.018 081861 060072_14 0.012017305 0.000166389 0.290788182 0.020563394 77.00425572 2.119511902 259.1664388 32.09527281 0.196799964 0.702877209 060072_15 0.010362978 6.97786E 05 0.068900696 0.00062282 66.45813479 0.890357154 67.65228277 1.182868466 0.744989311 0.017651259 060072_16 0.010627 5.83608E 05 0.106706859 0.003777842 68.14240091 0.744477626 102.9432553 6.920044067 0.155624029 0.338058616 060072_17 0.01046473 5.1172E 05 0.06997321 0.000980491 67.10728623 0.652881137 68.67053594 1.859985176 0.349163934 0.02276449

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130 Table C Continued Grain Name 206Pb/238U 1s error *207Pb/235U *1s 206Pb/238U 2 s error *207Pb/235U 2 s error RHO Discordance 060072_18 0.011999099 8.50114E 05 0.283006279 0.005867471 76.88829292 1.082961782 253.0266825 9.26550013 0.342005225 0.696125752 060072_19 0.010571874 4.84296E 05 0.079967173 0.001816715 67.79076993 0.617828273 78.11010831 3.413100288 0.201966221 0.132112714 060072_20 0.010739687 4.43857E 05 0.111227097 0.005264192 68.86112478 0.566145385 107.0818332 9.5971 00763 0.088007085 0.356929904 060072_21 0.010886597 3.64673E 05 0.084294052 0.000906198 69.798006 0.465080271 82.16989698 1.696416318 0.311739727 0.150564762 060072_22 0.010674738 4.84935E 05 0.107025402 0.002497366 68.44688416 0.618580205 103.2354553 4. 575864123 0.19501631 0.336982784 060072_23 0.010281182 5.39012E 05 0.070575 0.000700532 65.93624614 0.687826614 69.24143285 1.32833176 0.528298196 0.047734233 060072_24 0.01049111 8.15104E 05 0.071210063 0.000677664 67.27557369 1.039913848 69.84354722 1. 284222887 0.816509014 0.036767513 060072_25 0.007381906 3.11151E 05 0.049947499 0.000446645 47.41051169 0.398203272 49.48742169 0.863656141 0.471475534 0.041968442 060072_26 0.010773342 4.71658E 05 0.082557925 0.001000319 69.07576215 0.601585587 80.54288 729 1.875533222 0.361487885 0.142372909 060072_27 0.010951237 5.28641E 05 0.099220582 0.001907206 70.21018564 0.674145013 96.05174855 3.520254607 0.25140167 0.269037923 060072_28 0.010413946 6.83479E 05 0.085088717 0.002451581 66.78330954 0.872057534 82. 91374848 4.582776506 0.228197264 0.194544804 060072_29 0.023708278 0.001276824 1.360129612 0.11925512 151.0449382 16.07008773 871.8819554 100.0992987 0.615236823 0.826759876 060072_30 0.014425117 9.47496E 05 0.424567574 0.022185145 92.32298739 1.20412485 5 359.2936452 31.38030329 0.126454009 0.743043083

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131 APPENDIX D IGNEOUS AND DETRITAL Hf RESULTS Table D Hf isotopic analyses. Sample 176Lu/177Hf 1 s error 176Hf/177Hf 1 s error e(0) 2 s error t(Ga) 2 s error 176Hf/177Hf(t) e(t) Error 060065_03 0.0008606 22 0.0000095 0.283077 0.000016 10.32586594 1.131601747 0.0389 0.0011 0.28 11.17 1.16 060065_04 0.00160185 0.00021 0.283056 0.000011 9.583252294 0.777976201 0.0371 0.0010 0.28 10.37 0.81 060065_05 0.00491353 0.000035 0.282895 0.000019 3.889881005 1.343777 074 0.0369 0.0007 0.28 4.59 1.36 060065_06 0.00167724 0.000013 0.283072 0.000012 10.14905317 0.84870131 0.0373 0.0008 0.28 10.94 0.87 060065_07 0.00276099 0.000022 0.28303 0.000021 8.663825875 1.485227293 0.0373 0.0004 0.28 9.43 1.49 060065_08 0.0023791 5 0.000027 0.282996 0.000019 7.461499019 1.343777074 0.0380 0.0009 0.28 8.25 1.37 060065_09 0.00386648 0.00013 0.282981 0.000016 6.9310607 1.131601747 0.0365 0.0005 0.28 7.65 1.15 060065_10 0.000871307 0.000037 0.283033 0.000015 8.769913539 1.060876638 0 .0000 0.0000 0.28 8.77 1.06 060065_11 0.000884926 0.000054 0.283062 0.000013 9.795427622 0.919426419 0.0367 0.0004 0.28 10.59 0.93 060065_12 0.00200123 0.00015 0.283041 0.000014 9.052813975 0.990151529 0.0373 0.0005 0.28 9.83 1.01 060065_13 0.00378916 0 .000041 0.282969 0.000019 6.506710045 1.343777074 0.0378 0.0007 0.28 7.25 1.36 060065_15 0.00136711 0.000011 0.28302 0.000016 8.310200329 1.131601747 0.0363 0.0004 0.28 9.08 1.14 060065_16 0.00466346 0.00017 0.282956 0.00002 6.046996835 1.414502184 0.036 7 0.0007 0.28 6.75 1.44 060065_18 0.00174686 0.000049 0.283004 0.000016 7.744399455 1.131601747 0.0366 0.0006 0.28 8.51 1.15 060065_20 0.00226763 0.000034 0.282949 0.000019 5.799458953 1.343777074 0.0371 0.0005 0.28 6.57 1.36 060067_01 0.00 226428 0.000016 0.283057 0.000015 9.618614849 1.060876638 0.0369 0.0005 0.28 10.38 1.07 060067_04 0.00332007 0.000017 0.283026 0.000018 8.522375656 1.273051965 0.0362 0.0003 0.28 9.25 1.28 060067_06 0.00345326 0.000069 0.283068 0.000018 10.00760295 1.273 051965 0.0363 0.0004 0.28 10.73 1.29 060067_08 0.00298945 0.000073 0.283065 0.000019 9.901515285 1.343777074 0.0364 0.0004 0.28 10.64 1.36 060067_09 0.00137953 0.000096 0.283041 0.000017 9.052813975 1.202326856 0.0395 0.0013 0.28 9.89 1.24 060067_10 0.0 0346495 0.000016 0.283019 0.00002 8.274837774 1.414502184 0.0355 0.0005 0.28 8.98 1.43 060067_11 0.00257991 0.00013 0.283075 0.000016 10.25514083 1.131601747 0.0365 0.0003 0.28 11.00 1.15 060067_12 0.00488642 0.00004 0.283033 0.000019 8.769913539 1.34377 7074 0.0358 0.0003 0.28 9.45 1.35 060067_14 0.00183695 0.000024 0.283044 0.000018 9.158901639 1.273051965 0.0357 0.0005 0.28 9.91 1.28 060067_15 0.00559047 0.000056 0.283055 0.000022 9.54788974 1.555952402 0.0364 0.0004 0.28 10.22 1.57 060067_16 0.00321 233 0.0000058 0.28304 0.00002 9.017451421 1.414502184 0.0363 0.0004 0.28 9.75 1.42 060067_17 0.00350832 0.000024 0.283052 0.000012 9.441802076 0.84870131 0.0363 0.0005 0.28 10.16 0.86 060067_18 0.00228935 0.000044 0.282991 0.00002 7.284686246 1.414502184 0.0363 0.0003 0.28 8.04 1.42

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132 Table D Continued Sample 176Lu/177Hf 1 s error 176Hf/177Hf 1 s error e(0) 2 s error t(Ga) 2 s error 176Hf/177Hf(t) e(t) Error 060067_19 0.00394359 0.0000087 0.283085 0.000019 10.60876638 1.343777074 0.0355 0.0 004 0.28 11.31 1.35 060067_20 0.0015958 0.000043 0.283085 0.0000079 10.60876638 0.558728363 0.0365 0.0004 0.28 11.38 0.57 060072_02 0.00363986 0.000094 0.282911 0.000027 4.455681878 1.909577948 0.0668 0.0007 0.28 5.78 1.93 060072_03 0.00401 909 0.00026 0.283024 0.000016 8.451650547 1.131601747 0.0689 0.0007 0.28 9.80 1.17 060072_05 0.059749 0.0011 0.295882 0.0097 463.1433775 686.0335591 0.0000 0.0000 0.30 463.14 686.03 060072_06 0.00530033 0.00036 0.282925 0.0001 4.950757643 7.072510918 0.0 670 0.0005 0.28 6.20 7.12 060072_07 0.00450136 0.00011 0.282726 0.000038 2.086390721 2.687554149 0.0658 0.0009 0.28 0.82 2.72 060072_09 0.00447498 0.0001 0.282803 0.000037 0.636525983 2.61682904 0.0680 0.0005 0.28 1.95 2.64 060072_13 0.00594335 0.0002 4 0.282948 0.000085 5.764096398 6.01163428 0.0672 0.0008 0.28 6.99 6.05 060072_14 0.0044717 0.00032 0.282918 0.000042 4.703219761 2.970454586 0.0000 0.0000 0.28 4.70 2.97 060072_16 0.00375163 0.00026 0.282962 0.000023 6.259172163 1.626677511 0.0681 0.000 7 0.28 7.60 1.67 060072_17 0.00140699 0.000033 0.283029 0.000021 8.62846332 1.485227293 0.0671 0.0007 0.28 10.06 1.50 060072_18 0.102079 0.0038 0.266283 0.13 583.5528759 9194.264194 0.0000 0.0000 0.27 583.55 9194.26 060072_19 0.00281676 0.000098 0.283 126 0.00013 12.05863112 9.194264194 0.0678 0.0006 0.28 13.44 9.22 060072_20 0.00619307 0.00036 0.282749 0.000067 1.273051965 4.738582315 0.0689 0.0006 0.28 0.03 4.78 060072_23 0.00542854 0.00029 0.282955 0.000029 6.01163428 2.051028166 0.0659 0.0007 0. 28 7.24 2.09 060072_24 0.00444509 0.00033 0.282967 0.000034 6.435984936 2.404653712 0.0673 0.0010 0.28 7.73 2.46 070242_01 0.0046991 0.00036 0.28292 0.000028 4.77394487 1.980303057 0.0464 0.0007 0.28 5.66 2.02 070242_02 0.0114905 0.0003 0.2 82531 0.000042 8.982088866 2.970454586 0.0477 0.0005 0.28 8.29 3.00 070242_04 0.00917214 0.000053 0.282654 0.000039 4.632494651 2.758279258 0.0481 0.0013 0.28 3.86 2.79 070242_05 0.0114905 0.0003 0.282531 0.000042 8.982088866 2.970454586 0.0490 0.00 12 0.28 8.27 3.02 070242_06 0.00822276 0.00026 0.282745 0.000036 1.414502184 2.546103931 0.0487 0.0011 0.28 0.60 2.59 070242_07 0.00659779 0.000079 0.28306 0.000095 9.724702513 6.718885372 0.0515 0.0008 0.28 10.65 6.74 070242_08 0.00601823 0.000049 0 .282931 0.000028 5.16293297 1.980303057 0.0480 0.0012 0.28 6.04 2.01 070242_12 0.00199553 0.000048 0.283048 0.000015 9.300351857 1.060876638 0.0504 0.0020 0.28 10.35 1.11 070242_14 0.0120711 0.00039 0.282397 0.000059 13.72067118 4.172781442 0.0494 0.000 9 0.28 13.02 4.22 070242_15 0.00300284 0.000093 0.283143 0.000027 12.65979454 1.909577948 0.0485 0.0009 0.28 13.64 1.94 070242_18 0.00884767 0.00011 0.28275 0.000038 1.237689411 2.687554149 0.0493 0.0009 0.28 0.43 2.72 070242_19 0.00307022 0.00013 0. 283058 0.000033 9.653977403 2.333928603 0.0522 0.0011 0.28 10.71 2.37 070242_21 0.00207834 0.000014 0.28301 0.000017 7.956574783 1.202326856 0.0568 0.0012 0.28 9.14 1.23

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133 Table D Continued Sample 176Lu/177Hf 1 s error 176Hf/177Hf 1 s error e(0) 2 s error t(Ga) 2 s error 176Hf/177Hf(t) e(t) Error 070242_22 0.00364353 0.000079 0.283031 0.000018 8.699188429 1.273051965 0.0636 0.0021 0.28 9.96 1.33 070242_24 0.00180464 0.00003 0.283077 0.000017 10.32586594 1.202326856 0.0594 0.0018 0.28 11.58 1.25 070242_25 0.00148468 0.000011 0.283079 0.000015 10.39659105 1.060876638 0.0565 0.0011 0.28 11.60 1.09 070242_26 0.00913619 0.00006 0.28268 0.000032 3.713068232 2.263203494 0.0571 0.0015 0.28 2.79 2.30 070242_27 0.00285182 0.000042 0.283077 0.0000 13 10.32586594 0.919426419 0.0581 0.0013 0.28 11.51 0.95 070242_29 0.00663715 0.0000054 0.282881 0.000025 3.394805241 1.76812773 0.0587 0.0012 0.28 4.44 1.80 070242_30 0.0052919 0.000033 0.282916 0.00002 4.632494651 1.414502184 0.0597 0.0014 0.28 5.75 1. 45 070242_31 0.00916286 0.000012 0.28268 0.000028 3.713068232 1.980303057 0.0590 0.0010 0.28 2.76 2.01 070242_32 0.00249784 0.000038 0.283084 0.000024 10.57340382 1.69740262 0.0599 0.0020 0.28 11.81 1.75 070242_33 0.0143903 0.00014 0.28244 0.000054 1 2.20008133 3.819155896 0.0598 0.0013 0.28 11.44 3.86 070242_34 0.00495398 0.000045 0.282982 0.000015 6.966423254 1.060876638 0.0583 0.0016 0.28 8.07 1.10 070242_35 0.00320476 0.000093 0.283028 0.000019 8.593100766 1.343777074 0.0611 0.0020 0.28 9.82 1.4 0 070242_36 0.00796976 0.000025 0.282912 0.000026 4.491044433 1.838852839 0.0569 0.0011 0.28 5.45 1.87 070242_38 0.00149073 0.000024 0.283086 0.000013 10.64412893 0.919426419 0.0587 0.0012 0.28 11.89 0.95 070242_40 0.00501929 0.000018 0.282977 0.000022 6.789610481 1.555952402 0.0567 0.0012 0.28 7.86 1.59 070242_41 0.0190919 0.0003 0.282562 0.000096 7.885849674 6.789610481 0.0600 0.0016 0.28 7.31 6.85 070242_42 0.00824372 0.00012 0.282877 0.00002 3.253355022 1.414502184 0.0592 0.0013 0.28 4.25 1.45 0 70242_43 0.00304414 0.00011 0.28301 0.000028 7.956574783 1.980303057 0.0650 0.0018 0.28 9.27 2.03 070242_46 0.00742864 0.00019 0.282943 0.00002 5.587283625 1.414502184 0.0594 0.0015 0.28 6.61 1.46 070242_48 0.00471076 0.000029 0.283 0.000017 7.602949237 1.202326856 0.0615 0.0020 0.28 8.78 1.25 070242_50 0.00174827 0.000039 0.283118 0.000013 11.77573068 0.919426419 0.0604 0.0021 0.28 13.05 0.97 070242_52 0.00433879 0.000014 0.282983 0.000022 7.001785809 1.555952402 0.0610 0.0025 0.28 8.18 1.62 070242_53 0.00444693 0.000014 0.283035 0.000016 8.840638648 1.131601747 0.0602 0.0021 0.28 10.00 1.18 070242_55 0.00644335 0.00016 0.282896 0.000084 3.92524356 5.940909171 0.0710 0.0026 0.28 5.20 6.02 070242_57 0.00603589 0.0000071 0.282978 0.000027 6.824973036 1 .909577948 0.0598 0.0020 0.28 7.91 1.96 070242_59 0.00401872 0.00012 0.2831 0.000021 11.1392047 1.485227293 0.0599 0.0021 0.28 12.31 1.55 070242_60 0.00995365 0.00056 0.282751 0.000033 1.202326856 2.333928603 0.0623 0.0025 0.28 0.23 2.44 070242_62 0.0 0949111 0.00013 0.282765 0.000066 0.707251092 4.667857206 0.0625 0.0007 0.28 0.29 4.69 070242_64 0.00225511 0.00012 0.283103 0.000016 11.24529236 1.131601747 0.0622 0.0026 0.28 12.53 1.20 070242_65 0.00801131 0.000065 0.282847 0.000034 2.192478385 2.404 653712 0.0647 0.0028 0.28 3.29 2.48 070242_67 0.00797811 0.000071 0.282776 0.000029 0.318262991 2.051028166 0.0632 0.0020 0.28 0.75 2.10

PAGE 134

134 Table D Continued Sample 176Lu/177Hf 1 s error 176Hf/177Hf 1 s error e(0) 2 s error t(Ga ) 2 s error 176Hf/177Hf(t) e(t) Error 300351_01 0.00267678 0.000062 0.282977 0.000015 6.789610481 1.060876638 0.0473 0.0004 0.28 7.76 1.08 300351_02 0.00168727 0.000059 0.283101 0.000019 11.17456725 1.343777074 0.0476 0.0004 0.28 12.18 1.36 300351_03 0. 00313398 0.000047 0.282985 0.000018 7.072510918 1.273051965 0.0474 0.0006 0.28 8.03 1.29 300351_04 0.00134078 0.000034 0.283056 0.000011 9.583252294 0.777976201 0.0499 0.0012 0.28 10.65 0.81 300351_05 0.00652731 0.00008 0.282869 0.000025 2.970454586 1.76 812773 0.0551 0.0027 0.28 3.96 1.84 300351_06 0.00237227 0.000078 0.283 0.000014 7.602949237 0.990151529 0.0478 0.0010 0.28 8.59 1.02 300351_07 0.00543529 0.000077 0.282928 0.000018 5.056845307 1.273051965 0.0470 0.0005 0.28 5.93 1.29 300351_08 0.008973 77 0.00018 0.282847 0.000028 2.192478385 1.980303057 0.0466 0.0006 0.28 2.95 2.00 300351_10 0.00394046 0.00019 0.28297 0.000025 6.542072599 1.76812773 0.0459 0.0005 0.28 7.44 1.79 300351_13 0.00253864 0.00012 0.283037 0.000018 8.911363757 1.273051965 0.0 468 0.0006 0.28 9.87 1.29 300351_17 0.000746142 0.000033 0.28254 0.000016 8.663825875 1.131601747 0.2843 0.0041 0.28 2.48 1.24 300351_19 0.00213605 0.00019 0.283074 0.000035 10.21977828 2.475378821 0.0448 0.0005 0.28 11.15 2.50 300351_20 0.00493289 0. 00029 0.282921 0.000034 4.809307424 2.404653712 0.0505 0.0004 0.28 5.77 2.43 300351_23 0.00150814 0.000023 0.283026 0.000021 8.522375656 1.485227293 0.0461 0.0006 0.28 9.50 1.50 300351_24 0.00358314 0.000027 0.282936 0.000034 5.339745743 2.404653712 0.04 63 0.0006 0.28 6.26 2.42 300351_25 0.000738564 0.000063 0.283093 0.000025 10.89166681 1.76812773 0.0480 0.0022 0.28 11.94 1.82 300351_26 0.00554552 0.0000042 0.282923 0.000023 4.880032534 1.626677511 0.0458 0.0005 0.28 5.73 1.64 300351_32 0.00184665 0.0 00045 0.283018 0.000016 8.23947522 1.131601747 0.0457 0.0004 0.28 9.20 1.14 300351_33 0.0022869 0.00005 0.282994 0.000017 7.39077391 1.202326856 0.0493 0.0008 0.28 8.41 1.23 300351_35 0.0061765 0.0004 0.282854 0.000054 2.440016267 3.819155896 0.0468 0.00 05 0.28 3.29 3.86 300351_36 0.00456128 0.00003 0.283026 0.000027 8.522375656 1.909577948 0.0482 0.0004 0.28 9.45 1.92 300351_37 0.00250048 0.000068 0.283 0.000018 7.602949237 1.273051965 0.0471 0.0006 0.28 8.57 1.29 300351_39 0.00486845 0.00017 0.282896 0.000027 3.92524356 1.909577948 0.0458 0.0004 0.28 4.80 1.93 300351_40 0.000621998 0.000021 0.283034 0.000018 8.805276093 1.273051965 0.0431 0.0013 0.28 9.74 1.31 300351_43 0.00388493 0.00016 0.282967 0.000018 6.435984936 1.273051965 0.0471 0.0004 0.28 7.36 1.29 300351_44 0.0046224 0.000077 0.282923 0.000023 4.880032534 1.626677511 0.0451 0.0004 0.28 5.74 1.64 300351_45 0.00295063 0.000016 0.283003 0.000018 7.709036901 1.273051965 0.0458 0.0005 0.28 8.64 1.29 300351_46 0.00408734 0.00011 0.282961 0.00 0018 6.223809608 1.273051965 0.0455 0.0004 0.28 7.11 1.29 300351_47 0.00243356 0.000088 0.282946 0.000025 5.693371289 1.76812773 0.0475 0.0011 0.28 6.67 1.80 300351_49 0.00187268 0.000029 0.283025 0.000016 8.487013102 1.131601747 0.0468 0.0006 0.28 9.47 1.15 300339_1_01 0.00272354 0.000049 0.283083 0.000011 10.53804127 0.777976201 0.0547 0.0020 0.28 11.65 0.83

PAGE 135

135 Table D Continued Sample 176Lu/177Hf 1 s error 176Hf/177Hf 1 s error e(0) 2 s error t(Ga) 2 s error 176Hf/177Hf(t) e( t) Error 300339_1_02 0.0013063 0.000039 0.283113 0.000017 11.59891791 1.202326856 0.0512 0.0014 0.28 12.69 1.24 300339_1_03 0.00769312 0.00023 0.28299 0.000048 7.249323691 3.394805241 0.0618 0.0019 0.28 8.31 3.46 300339_1_04 0.00262551 0.00019 0.28294 0 .000022 5.481195962 1.555952402 0.0000 0.0000 0.28 5.48 1.56 300339_1_06 0.00357786 0.000079 0.283089 0.000023 10.7502166 1.626677511 0.0492 0.0021 0.28 11.73 1.68 300339_1_07 0.00213511 0.000076 0.283048 0.000021 9.300351857 1.485227293 0.0508 0.0018 0. 28 10.36 1.53 300339_1_08 0.00366665 0.0001 0.283074 0.000036 10.21977828 2.546103931 0.0473 0.0019 0.28 11.16 2.60 300339_1_09 0.00181994 0.000081 0.28302 0.000012 8.310200329 0.84870131 0.0500 0.0021 0.28 9.36 0.90 300339_1_10 0.00685337 0.0002 0.2830 26 0.000022 8.522375656 1.555952402 0.0476 0.0016 0.28 9.36 1.61 300339_1_11 0.0071064 0.00029 0.283115 0.00002 11.66964302 1.414502184 0.0582 0.0016 0.28 12.69 1.47 300339_1_12 0.00149733 0.000022 0.28307 0.000015 10.07832806 1.060876638 0.0454 0.0015 0 .28 11.04 1.10 300339_1_13 0.00642725 0.000034 0.283116 0.000027 11.70500557 1.909577948 0.0584 0.0018 0.28 12.76 1.95 300339_1_14 0.00161005 0.00002 0.283071 0.000017 10.11369061 1.202326856 0.0468 0.0014 0.28 11.10 1.24 300339_1_15 0.00108186 0.00011 0.283005 0.000021 7.77976201 1.485227293 0.0490 0.0012 0.28 8.83 1.52 300339_1_16 0.00214085 0.000037 0.283173 0.000016 13.72067118 1.131601747 0.0450 0.0014 0.28 14.66 1.17 300339_1_17 0.00181137 0.000023 0.283074 0.000018 10.21977828 1.273051965 0.0467 0.0012 0.28 11.20 1.30 300339_1_18 0.00347708 0.00016 0.283086 0.000035 10.64412893 2.475378821 0.0468 0.0018 0.28 11.58 2.53 300339_1_19 0.00329629 0.00011 0.283097 0.000023 11.03311703 1.626677511 0.0471 0.0017 0.28 11.98 1.67 300339_1_20 0.00351469 0.000051 0.283031 0.000018 8.699188429 1.273051965 0.0458 0.0016 0.28 9.61 1.31 300339_1_21 0.00157167 0.000074 0.283034 0.000021 8.805276093 1.485227293 0.0525 0.0022 0.28 9.92 1.54 300339_1_22 0.00122372 0.000041 0.283037 0.000016 8.911363757 1.1316017 47 0.0479 0.0020 0.28 9.94 1.18 300339_1_23 0.00345798 0.00006 0.283129 0.000017 12.16471878 1.202326856 0.0590 0.0019 0.28 13.34 1.25 300339_1_24 0.00662392 0.00013 0.283114 0.000018 11.63428046 1.273051965 0.0588 0.0016 0.28 12.68 1.32 300339_1_25 0.0 015038 0.000032 0.28308 0.000018 10.4319536 1.273051965 0.0488 0.0016 0.28 11.47 1.31 300339_1_26 0.00318503 0.000084 0.283018 0.000018 8.23947522 1.273051965 0.0461 0.0011 0.28 9.17 1.30 300339_1_27 0.00610346 0.000087 0.283095 0.000025 10.96239192 1.76 812773 0.0581 0.0018 0.28 12.02 1.82 300339_1_28 0.00629073 0.000088 0.282975 0.000028 6.718885372 1.980303057 0.0469 0.0014 0.28 7.57 2.02 300339_1_29 0.00439585 0.000072 0.283115 0.000016 11.66964302 1.131601747 0.0570 0.0021 0.28 12.77 1.19 300339_1_ 30 0.00249954 0.000098 0.283043 0.00002 9.123539084 1.414502184 0.0476 0.0020 0.28 10.10 1.47 300339_1_31 0.00189924 0.000094 0.283033 0.000019 8.769913539 1.343777074 0.0466 0.0012 0.28 9.75 1.38 300339_1_32 0.00295491 0.000097 0.283094 0.000016 10.9270 2937 1.131601747 0.0467 0.0014 0.28 11.87 1.17 300339_1_33 0.00312232 0.00021 0.282996 0.000021 7.461499019 1.485227293 0.0490 0.0018 0.28 8.45 1.54 300339_1_34 0.00627842 0.0003 0.282928 0.000085 5.056845307 6.01163428 0.0484 0.0012 0.28 5.93 6.06

PAGE 136

136 Table D Continued Sample 176Lu/177Hf 1 s error 176Hf/177Hf 1 s error e(0) 2 s error t(Ga) 2 s error 176Hf/177Hf(t) e(t) Error 300339_1_35 0.00269833 0.00015 0.283074 0.000013 10.21977828 0.919426419 0.0494 0.0011 0.28 11.23 0.95 300339_1_36 0. 000975821 0.000055 0.283058 0.000022 9.653977403 1.555952402 0.0471 0.0016 0.28 10.67 1.60 300339_1_37 0.00114089 0.000019 0.283086 0.000018 10.64412893 1.273051965 0.0463 0.0017 0.28 11.64 1.31 300339_1_38 0.00166504 0.000016 0.283134 0.000014 12.341531 55 0.990151529 0.0449 0.0011 0.28 13.29 1.02 300339_1_39 0.00148359 0.000012 0.283064 0.000014 9.866152731 0.990151529 0.0473 0.0016 0.28 10.87 1.03 300339_1_40 0.00797928 0.000074 0.283085 0.000027 10.60876638 1.909577948 0.0591 0.0018 0.28 11.61 1.96 300339_1_41 0.00334023 0.000095 0.283116 0.000019 11.70500557 1.343777074 0.0507 0.0012 0.28 12.72 1.38 300339_1_42 0.00215757 0.000055 0.282987 0.000014 7.143236027 0.990151529 0.0464 0.0016 0.28 8.11 1.03 300339_1_43 0.00183083 0.000053 0.28304 0.00001 9 9.017451421 1.343777074 0.0495 0.0018 0.28 10.06 1.39 300339_1_44 0.005329 0.00015 0.283041 0.000029 9.052813975 2.051028166 0.0477 0.0017 0.28 9.94 2.10 300339_1_45 0.00198772 0.000049 0.283003 0.000083 7.709036901 5.870184062 0.0528 0.0012 0.28 8.81 5.90 300339_1_46 0.00332373 0.00021 0.283119 0.00002 11.81109323 1.414502184 0.0498 0.0032 0.28 12.81 1.50 300339_1_49 0.00109581 0.000053 0.283044 0.000015 9.158901639 1.060876638 0.0456 0.0010 0.28 10.14 1.09 300339_1_54 0.00735514 0.000077 0.283148 0 .000038 12.83660732 2.687554149 0.0558 0.0014 0.28 13.81 2.73 300339_1_56 0.00412682 0.00021 0.283045 0.000019 9.194264194 1.343777074 0.0476 0.0010 0.28 10.12 1.38 300339_1_57 0.00094793 0.000014 0.283065 0.000014 9.901515285 0.990151529 0.0410 0.0015 0 .28 10.79 1.03 300339_1_59 0.00667205 0.000022 0.283189 0.000032 14.28647205 2.263203494 0.0582 0.0017 0.28 15.32 2.31 300339_1_60 0.00473171 0.000058 0.283122 0.000029 11.9171809 2.051028166 0.0575 0.0015 0.28 13.02 2.09 300339_1_61 0.0010626 0.00004 0 .282988 0.00002 7.178598582 1.414502184 0.0502 0.0015 0.28 8.26 1.45 300339_1_64 0.00326718 0.000095 0.283145 0.000035 12.73051965 2.475378821 0.0449 0.0018 0.28 13.63 2.52 300339_1_65 0.00548952 0.000069 0.283208 0.000015 14.95836059 1.060876638 0.0577 0.0021 0.28 16.03 1.11 300339_1_67 0.00791866 0.00018 0.283139 0.000029 12.51834433 2.051028166 0.0565 0.0019 0.28 13.48 2.11 300339_1_68 0.00216008 0.00007 0.283028 0.000015 8.593100766 1.060876638 0.0465 0.0024 0.28 9.56 1.12 300339_1_69 0.00563762 0. 000074 0.283075 0.000023 10.25514083 1.626677511 0.0556 0.0019 0.28 11.28 1.68 300334_01 0.0015878 0.00014 0.283077 0.00002 10.32586594 1.414502184 0.0428 0.0013 0.28 11.23 1.45 300334_02 0.00143172 0.0000046 0.283087 0.000022 10.67949149 1. 555952402 0.0457 0.0019 0.28 11.65 1.60 300334_03 0.000914887 0.000013 0.28313 0.000015 12.20008133 1.060876638 0.0429 0.0007 0.28 13.13 1.08 300334_04 0.0018822 0.000081 0.283098 0.000016 11.06847959 1.131601747 0.0415 0.0009 0.28 11.94 1.16 300334_06 0.000603479 0.000017 0.283101 0.000014 11.17456725 0.990151529 0.0454 0.0013 0.28 12.16 1.02 300334_07 0.00172397 0.00015 0.283033 0.000027 8.769913539 1.909577948 0.0440 0.0014 0.28 9.70 1.95 300334_08 0.000924361 0.000005 0.283061 0.00002 9.760065067 1 .414502184 0.0430 0.0009 0.28 10.69 1.44

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137 Table D Continued Sample 176Lu/177Hf 1 s error 176Hf/177Hf 1 s error e(0) 2 s error t(Ga) 2 s error 176Hf/177Hf(t) e(t) Error 300334_09 0.0012685 0.000042 0.28308 0.000018 10.4319536 1.273051965 0.0 491 0.0023 0.28 11.48 1.33 300334_10 0.00288888 0.00012 0.282763 0.00011 0.777976201 7.77976201 0.0442 0.0020 0.28 0.12 7.83 300334_11 0.00132689 0.000054 0.283169 0.000018 13.57922096 1.273051965 0.0420 0.0007 0.28 14.48 1.29 300334_12 0.00141127 0.00 0048 0.283237 0.000081 15.98387468 5.728733844 0.0448 0.0024 0.28 16.94 5.79 300334_13 0.000969623 0.000019 0.283077 0.000016 10.32586594 1.131601747 0.0414 0.0006 0.28 11.22 1.15 300334_15 0.00128647 0.000021 0.283094 0.00003 10.92702937 2.121753275 0.0 432 0.0007 0.28 11.85 2.14 300334_16 0.0027259 0.00006 0.283099 0.000019 11.10384214 1.343777074 0.0400 0.0006 0.28 11.92 1.36 300334_17 0.00343475 0.00014 0.283135 0.000021 12.37689411 1.485227293 0.0450 0.0004 0.28 13.27 1.50 300334_18 0.000823962 0.0 00029 0.283133 0.000021 12.306169 1.485227293 0.0404 0.0005 0.28 13.18 1.50 300334_19 0.00115218 0.000028 0.283005 0.00002 7.77976201 1.414502184 0.0412 0.0005 0.28 8.66 1.43

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138 LIST OF REFERENCES Acton, G. D., Galbrun, B., and King, J. W., 2000, Paleolatt itude of the Caribbean Plate since the late Cretaceous: Proceedings of the Ocean Drilling Program, Scientific Results, v. 165, p. 149 173. Barckhausen, U., Ranero, C. R., Cande, S. C., Engels, M., and Weinrebe, W., 2008, Birth of an intraoceanic spreading center: Geology, v. 36, no. 10, p. 767 770. Bernet, M., and Spiegel, C., 2004, Introduction: Detrital thermochronology: Geological Society of America Special Papers, v. 378, p. 1 6. Beu, A. G., 2001, Gradual Miocene to Pleistocene uplift of the Central Ame rican Isthmus: Evidence from tropical american Tonnoidean gastropods: Journal of Paleontology, v. 75, no. 3, p. 706 720. Black, L. P., Kamo, S. L., Williams, I. S., Mundil, R., Davis, D. W., Korsch, R. J., and Foudoulis, C., 2003, The application of SHRIMP to Phanerozoic geochronology; 171 188. Blichert Toft, J., and Albarede, F., 1997, The Lu Hf isotope geochemistry of chondrites and the evolution of the mantle crust syste m: Earth and Planetary Science 258. Buchs, D. M., Arculus, R. J., Baumgartner, P. O., Baumgartner Mora, C., and Ulianov, A., 2010, Late Cretaceous arc development on the SW margin of the Caribbean Plate: Insights from the G olfito, Costa Rica, and Azuero, Panama, complexes: Geochem. Geophys. Geosyst., v. 11, no. 7, p. Q07S24. Buchs, D. M., Baumgartner, P. O., Baumgartner Mora, C., Bandini, A. N., Jackett, S. J., Dise rens, M.O., and Stucki, J ., 2009, Late Cretaceous to Miocene seamount accretion and melange formation in the Osa and Burica Peninsulas (Southern Costa Rica): episodic growth of a convergent margin: Geological Society, London, Special Publications, v. 328, no. 1, p. 411 456. Buchs, D. M., Baumgartner, P. O., Baumgart ner Mora, C., Flores, K., and Bandini, A., 2011, Upper Cretaceous to Miocene tectonostratigraphy of the Azuero area (Panama) and the discontinuous accretion and subduction erosion along the Middle American margin: Tectonophysics, no. 512, p. 31 46. Budd, A. F., Stemann, T. A., and Stewart, R. H., 1992, Eocene Caribbean reef corals; a unique fauna from the Gatuncillo Formation of Panama: Journal of Paleontology, v. 66, no. 4, p. 570 594.

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139 Cardona, A., Valencia, V., Garzon, A., Montes, C., Ojeda, G., Ruiz, J ., and Weber, M., 2010, Permian to Triassic I to S type magmatic switch in the northeast Sierra Nevada de Santa Marta and adjacent regions, Colombian Caribbean: Tectonic setting and implications within Pangea paleogeography: Journal of South American earth sciences, v. 29, no. 4, p. 772 783. Coates, A. G., Collins, L. S., Aubry, M. P., and Berggren, W. A., 2004, The Geology of the Darien, Panama, and the late Miocene Pliocene collision of the Panama arc with northwestern South America: Geological Society of America Bulletin, v. 116, no. 11 12, p. 1327 1344. Coates, A. G., Jackson, J. C., Collins, L. S., Cronin, T. M., Dowsett, H. J., Bybell, L. M., Jung, P., and Obando, J. A., 1992, Closure of the Isthmus of Panama: The near shore marine record of Costa Rica and western Panama: Geological Society of America Bulletin, v. 104, no. 7, p. 814 828. Cole, W. S., 1949, Upper Eocene larger Foraminifera from the Panama Canal Zone: Journal of Paleontology, v. 23, no. 3, p. 267 275. Collins, L. S., Coates, A. G., Berggr en, W. A., Aubry, M. P., and Zhang, J., 1996, The late Miocene Panama isthmian strait: Geology, v. 24, no. 8, p. 687 690. Cooke, C. W., 1948, Eocene echinoids from Panama: Journal of Paleontology, v. 22, no. 1, p. 91 93. Corral, I., 2013, Geology and metal logeny of the Cerro Quema Au Cu deposit (Azuero Peninsula, Panama) [PhD: Universitat Autonoma de Barcelona, 192 p. Coryell, H. N., and Embich, J. R., 1937, The Tranquilla Shale (Upper Eocene) of Panama and Its Foraminiferal Fauna: Journal of Paleontology, v. 11, no. 4, p. 289 305. infer maximum depositional ages of strata: A test against a Colorado Plateau Mesozoic database: Earth and Planetary Science Letters, v. 288, no. 125. Duque Caro, H., 1990, Neogene stratigraphy, paleoceanography and paleobiogeography in northwest South America and the evolution of the Panama seaway: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 77, no. 3 4, p. 203 234. Farley, K A., 2000, Helium diffusion from apatite: General behavior as illustrated by Durango fluorapatite: Journal of Geophysical Research: Solid Earth, v. 105, no. B2, p. 2903 2914. Farley, K. A., 2002, (U Th)/He dating: Techniques, calibrations, and application s, Noble Gases in Geochemistry and Cosmochemistry, Volume 47, p. 819 844.

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140 Farley, K. A., Wolf, R. A., and Silver, L. T., 1996, The effects of long alpha stopping distances on (U Th)/He ages: Geochimica et Cosmochimica Acta, v. 60, no. 21, p. 4223 4229. Far ris, D. W., Jaramillo, C., Bayona, G., Restrepo Moreno, S. A., Montes, C., Cardona, A., Mora, A., Speakman, R. J., Glascock, M. D., and Valencia, V., 2011, Fracturing of the Panamanian Isthmus during initial collision with South America: Geology, v. 39, no 11, p. 1007 1010. Flowerdew, M. J., Millar, I. L., Curtis, M. L., Vaughan, A. P. M., Horstwood, M. S. A., Whitehouse, M. J., and Fanning, C. M., 2007, Combined U Pb geochronology and Hf isotope geochemistry of detrital zircons from early Paleozoic sedime ntary rocks, Ellsworth Whitmore Mountains block, Antarctica: Geological Society of America Bulletin, v. 119, no. 3 4, p. 275 288. Gehrels, G., Valencia, V., and Pullen, A., 2006, Detrital zircon geochronology by laser ablation multicollector ICPMS at the A rizona LaserChron Center: The Paleontological Society Papers, v. 12, p. 67 76. Gerdes, A., and Zeh, A., 2009, Zircon formation versus zircon alteration: New insights from combined U Pb and Lu Hf in situ LA ICP MS analyses, and consequences for the interp retation of Archean zircon from the Central Zone of the Limpopo 243. Graham, A., 1985, Studies in neotropical paleobotany. IV. The Eocene communities of Panama: Annals of the Missouri Botanical Garden, v. 72, p. 504 534. Graham, A., Stewart, R. H., and Stewart, J. L., 1985, Studies in Neotropical Paleobotany. III. The Tertiary Communities of Panama Geology of the pollen bearing deposits: Annals of the Missouri Botanical Garden, v. 72, no. 3, p. 485 503. He rrera, F., Manchester, S. R., and Jaramillo, C., 2012, Permineralized fruits from the late Eocene of Panama give clues of the composition of forests established early in the uplift of Central America: Review of Palaeobotany and Palynology, v. 175, no. 0, p 10 24. Hoernle, K., van den Bogaard, P., Werner, R., Lissinna, B., Hauff, F., Alvarado, G., and Garbe Schonberg, D., 2002, Missing history (16 71 Ma) of the Galapagos hotspot: Implications for the tectonic and biological evolution of the Americas: Geolog y, v. 30, no. 9, p. 795 798. Iizuka, T., Hirata, T., Komiya, T., Rino, S., Katayama, I., Motoki, A., and Maruyama, S., 2005, U Pb and Lu Hf isotope systematics of zircons from the Mississippi River sand: Implications for reworking and growth of continental crust: Geology, v. 33, no. 6, p. 485 488.

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141 James, K. H., 2009, In situ origin of the Caribbean: discussion of data: Geological Society, London, Special Publications, v. 328, no. 1, p. 77 125. Kameo, K., and Sato, T., 2000, Biogeography of Neogene calcareou s nannofossils in the Caribbean and the eastern equatorial Pacific floral response to the emergence of the Isthmus of Panama: Marine Micropaleontology, v. 39, no. 1 4, p. 201 218. Keigwin, L., 1982, Isotopic Paleoceanography of the Caribbean and East Pacif ic: Role of Panama Uplift in Late Neogene Time: Science, v. 217, no. 4557, p. 350 353. Keigwin, L. D., 1978, Pliocene closing of the Isthmus of Panama, based on biostratigraphic evidence from nearby Pacific Ocean and Caribbean Sea cores: Geology, v. 6, no. 10, p. 630 634. Kinny, P. D., and Maas, R., 2003, Lu Hf and Sm Nd isotope systems in zircon, in Hanchar, J. M., and Hoskin, P. W. O., eds., Zircon: Mineralogical Society of America Reviews in Mineralogy and Geochemistry, Volume 53, p. 327 341. Kolarsky, R A., Mann, P., Monechi, S., Meyerhoff, H. D., and Pessagno Jr., E. A., 1995, Stratigraphic development of southwestern Panama as determined from integration of marine seismic data and onshore geology, in Mann, P., ed., Geologic and tectonic development of the Caribbean Plate boundary in southern Central America, p. 159 200. Krawinkel, H., Wozazek, S., Krawinkel, J., and Hellmann, W., 1999, Heavy mineral analysis and clinopyroxene geochemistry applied to provenance analysis of lithic sandstones from the A zuero Sona Complex (NW Panama): Sedimentary Geology, v. 124, no. 1 4, p. 149 168. Lissinna, B., 2005, A profile through the Central American Landbridge in western Panama: 155 Ma Interplay between the Galapagos Hotspot and the Central American Subduction Zo ne [PhD: Christian Albrechts Universitaet, 116 p. Ludwig, K. R., 2008, Isoplot 3.6, Berkeley Geochronology Center Special Publication, 77 p.: Mann, P., Rogers, R., and Gahagan, L., 2007, Overview of plate tectonic history and its unresolved tectonic proble ms, in Bundschuh, J., and Alvarado, G., eds., Central America: Geology, Resources and Hazards, Volume 1, Taylor & Francis, London, p. 201 237. Meschede, M., and Frisch, W., 1998, A plate tectonic model for the Mesozoic and Early Cenozoic history of the C aribbean plate: Tectonophysics, v. 296, no. 3 4, p. 269 291.

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142 Montes, C., Bayona, G., Cardona, A., D., B., Silva, C., Morn, S., Hoyos, N., Ramrez, D., Jaramillo, C., and Valencia, V., 2012b, Arc Continent Collision and Orocline Formation: Closing of the C entral American Seaway: Journal of Geophysical Research, Solid Earth. Montes, C., Cardona, A., McFadden, R. R., Moron, S. E., Silva, C. A., Restrepo Moreno, S. A., Ramirez, D. A., Hoyos, N., Wilson, J., Farris, D., Bayona, G. A., Jaramillo, C. A., Valencia V., Bryan, J., and Flores, J. A., 2012a, Evidence for middle Eocene and younger land emergence in Central Panama: implications for Isthmus closure: Geological Society of America Bulletin. Morag, N., Avigad, D., Gerdes, A., Belousova, E., and Harlavan, Y. 2011, Detrital zircon Hf isotopic composition indicates long distance transport of North Gondwana Cambrian Ordovician sandstones: Geology, v. 39, no. 10, p. 955 958. Morell, K. D., Kirby, E., Fisher, D. M., and van Soest, M., 2012, Geomorphic and exhumat ional response of the Central American Volcanic Arc to Cocos Ridge subduction: Journal of Geophysical Research: Solid Earth, v. 117, no. B4, p. B04409. Moreno, J. F., Foster, D., Montes, C., Rooney, T., and Jaramillo, C., 2012, Implications of late Miocene volcanism for closing the panamanian seaway: Geological Society of America Abstracts with Programs, v. 44, no. 7, p. 60. Mueller, P. A., Kamenov, G. D., Heatherington, A. L., and Richards, J., 2008, Crustal Evolution in the Southern Appalachian Orogen: Ev idence from Hf Isotopes in Detrital Zircons: The Journal of Geology, v. 116, no. 4, p. 414 422. Newkirk, D. R., and Martin, E. E., 2009, Circulation through the Central American Seaway during the Miocene carbonate crash: Geology, v. 37, no. 1, p. 87 90. No well, G. M., Kempton, P. D., Noble, S. R., Fitton, J. G., Saunders, A. D., Mahoney, J. J., and Taylor, R. N., 1998, High precision Hf isotope measurements of MORB and OIB by thermal ionisation mass spectrometry: insights into the depleted mantle: Chemical 233. Patchett, P. J., Vervoort, J. D., Soderlund, U., and Salters, V. J. M., 2004, Lu Hf and Sm Nd isotopic systematics in chondrites and their constraints on the Lu Hf properties of the Earth: Earth and Planetary Science L etters, v. 222, no. 1, p. 29 41. Pindell, J. L., 1990, Geological arguments suggesting a Pacific origin for the Caribbean Plate, in Larue, D. K., and Draper, G., eds., Transactions of the 12th Caribbean Geologic Conference: St Croix, 7 11 August 1989, M iami Geological Society, Miami, Fl, p. 1 4.

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143 Pindell, J. L., and Kennan, L., 2001, Kinematic Evolution of the Gulf of Mexico and Caribbean: GCSSEPM Foundation 21st Annual Research Conference Transactions, Petroleum Systems of Deep Water Basins p. 193 220 Pindell, J. L., and Kennan, L., 2009, Tectonic evolution of the Gulf of Mexico, Caribbean and northern South America in the mantle reference frame: an update: Geological Society, London, Special Publications, v. 328, no. 1, p. 1 55. Rahl, J. M., Reiners, P. W., Campbell, I. H., Nicolescu, S., and Allen, C. M., 2003, Combined single grain (U Th)/He and U/Pb dating of detrital zircons from the Navajo Sandstone, Utah: Geology, v. 31, no. 9, p. 761 764. Recchi, G., and Metti, A., 1975, Lamina 17: Instituto To mmy Guardia. Reeves, F., and Ross, C. P., 1930, A geologic study of the Madden Dam Project, Alhajuela, Canal Zone: U.S. Geological Survey Bulletin, v. 821, p. 11 49 Rincn, A., Bloch, J., Foster, D., MacFadden, B. J., and Jaramillo, C., 2012, The Las Ca scadas fossil assemblage: Biostratigraphic and paleobiogeographic implications of the oldest mammals from the Panama Canal area, Central America: Geological Society of America Abstracts with Programs, v. 44, no. 7, p. 163. Rooney, T., Franceschi, P., and H all, C., 2011, Water saturated magmas in the Panama Canal region: a precursor to adakite like magma generation?: Contributions to Mineralogy and Petrology, v. 161, no. 3, p. 373 388. Shan, J., Min, K., and Nouiri, A., 2013, Thermal effects of scanning elec tron microscopy on He diffusion in apatite: Implications for (UTh)/He dating: Chemical Geology, v. 345, no. 0, p. 113 118. Sinton, C. W., Sigurdsson, H., and Duncan, R. A., 2000, 15. Geochronology and petrology of the igneous basement at the lower Nicaraguan Rise, Site 1001, in Leckie, R. M., Sigurdsson, H., Acton, G. D., and Draper, G., eds., Proceedings of the Ocean Drilling Program, Scientific Results, Volume 165: College Station, Texas. Stewart, R. H., Stewart, J. L., and Woodring, W. P., 1980, Geologic map of the Panama Canal and Vicinity, Republic of Panama: U.S. Geological Survey Miscellaneous Investigations Series Map I 1232, scale 1:100.000, 1 sheet. Terry, R. A., 1956, A geological reconnaissance of Panama: California Academy of Sciences Occasional Paper, v. 23, p. 91. Thompson, T. F., 1944, Geological explorations in the vicinity of Rio Quebrancha for the Panama Cemen t Company: Panama City, Panama Canal, Special Engineering Division.

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144 Tripati, A., and Zachos, J., 2002, Late Eocene tropical sea surface temperatures: A perspective from Panama: Paleoceanography, v. 17, no. 3, p. 1032. Vaughan, T. W., 1926, The stratigraphi c horizon of the beds containing Lepidocyclina Chaperi on Haut Chagres, Panama: Proceedings of the National Academy of Science, v. 12, p. 519 522. Vermeesch, P., 2012, On the visualisation of detrital age distributions: Chemical 0, p. 190 194. Vervoort, J. D., and Blichert Toft, J., 1999, Evolution of the depleted mantle: Hf isotope evidence from juvenile rocks through time: Geochimica et Cosmochimica Acta, v. 556. Villagomez, D., and Spikings, R., 2013, Thermo chronology and tectonics of the Central and Western Cordilleras of Colombia: Early Cretaceous Tertiary evolution of the Northern Andes: Lithos, v. 160 161, no. 0, p. 228 249. Villeneuve, M., 1997, Report on 40Ar/39Ar age dates for samples from Petaquilla d eposit: Unpublished report by Geological Survey of Canada for Inmet Mining, p. 4. Wegner, W., Wrner, G., Harmon, R. S., and Jicha, B. R., 2011, Magmatic history and evolution of the Central American Land Bridge in Panama since Cretaceous times: Geological Society of America Bulletin, v. 123, no. 3 4, p. 703 724. Whattam, S. A., Montes, C., McFadden, R. R., Cardona, A., Ramirez, D., and Valencia, V., 2012, Age and origin of earliest adakitic like magmatism in Panama: Implications for the tectonic evolution of the Panamanian magmatic arc system: Lithos, v. 142 143, no. 0, p. 226 244. Woodring, W. P., 1957, Geology and description of Tertiary mollusks (Gastropods; Trochidae to Turritellidae), U.S. Geological Survey Professional Paper, Geology and Paleontology of Canal Zone and adjoining parts of Panama 145 p.: Woodring, W. P., and Thompson, T. F., 1949, Tertiary formations of Panama Canal Zone and adjoining parts of Panama: AAPG Bulletin, v. 33, no. 2, p. 223 247. Wu, F. Y., 2010, Geochemical applications on in situ isotopic analyses by laser ablation: Geochemical News, v. 143, p. 1 16.

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145 BIOGRAPHICAL SKETCH Diego A. Ramrez S. of Colombia, Bucaramanga. When he was 17 years old graduated from FCUIS high school and decided to go to st udy in the city of Medelln. In 2006 earned his bachelor in Geology at the Universidad E AFIT after his research on the age and provenance of the volcaniclastic rocks of the Combia Formation T hen he moved to Bogot and from 2007 to 2009 worked fo r the oil field services company Geoservices (Schlumberger) In July of 2009, he accepted an internship at the Smithsonian Tropical Research I nstitute in Panama City, Panama, and worked alongside Dr. Camilo Montes, Dr. Carlos Jaramillo, Dr. Rory McFadden a nd Dr. Austin Hendy in the Panama Geology Project. The results of this research were com piled in three published papers in which he served as Arc Continent Collision and Orocline Formation: Closing of the Central American Seaway Evidence for middle Eocene and younger land emergence in Central Panama: implications for Isthmus closure Age and origin of earliest adakitic like magmatism in Panama: Implications for the tectonic evolution of the Panamanian magmatic arc system Now, after 2.5 years of study away from home, he is about to earn his degree in Geology from the University of Florida.