<%BANNER%>
HIDE
 Title Page
 Introduction and methods
 Results
 Discussion
 Acknowledgment and references
 Appendix


FGS



Lithology and palynology of cave floor sediment cores from Wakulla Spring, Wakulla County, Florida ( FGS: Open file repo...
CITATION SEARCH THUMBNAILS PDF VIEWER PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00001046/00001
 Material Information
Title: Lithology and palynology of cave floor sediment cores from Wakulla Spring, Wakulla County, Florida ( FGS: Open file report 47 )
Series Title: ( FGS: Open file report 47 )
Physical Description: 9 p. : ill., maps ; 28 cm.
Language: English
Creator: Rupert, Frank
Florida Geological Survey
Publisher: Florida Geological Survey
Place of Publication: Tallahassee
Publication Date: 1991
 Subjects
Subjects / Keywords: Petrology -- Florida -- Wakulla County   ( lcsh )
Palynology -- Florida -- Wakulla County   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
bibliography   ( marcgt )
non-fiction   ( marcgt )
 Notes
Statement of Responsibility: by Frank R. Rupert.
Bibliography: Includes bibliographical references (p. 7).
General Note: Cover title.
Funding: Digitized as a collaborative project with the Florida Geological Survey, Florida Department of Environmental Protection.
 Record Information
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management:
The author dedicated the work to the public domain by waiving all of his or her rights to the work worldwide under copyright law and all related or neighboring legal rights he or she had in the work, to the extent allowable by law.
Resource Identifier: aleph - 001754166
oclc - 26607205
notis - AJG7155
System ID: UF00001046:00001

Downloads

This item has the following downloads:

UF00001046 ( PDF )


Table of Contents
    Title Page
        Title Page 1
        Title Page 2
    Introduction and methods
        Page 1
        Page 2
        Page 3
    Results
        Page 4
        Page 3
        Page 5
    Discussion
        Page 6
        Page 5
        Page 7
    Acknowledgment and references
        Page 7
    Appendix
        Page 8
        Page 9
        Copyright
            Main
Full Text














STATE OF FLORIDA
DEPARTMENT OF NATURAL RESOURCES
Virginia Wctherell. Executive Director





DIVISION OF RESOURCE MANAGEMENT
Jeremy A. Craft, Director





FLORIDA GEOLOGICAL SURVEY
Walter Schmidt, State Geologist and Chief






OPEN FILE REPORT NO. 47

LITHOLOGY AND PALYNOLOGY OF CAVE FLOOR SEDIMENT CORES
FROM WAKULLA SPRING, WAKULLA COUNTY, FLORIDA

BY

FRANK R. RUPERT


FLORIDA GEOLOGICAL SURVEY
Tallahassee
1991










cicq



Sc j*t-









Lithology and Palynology of cave floor
sediment cores from Wakulla Spring,
Wakulla County, Florida
by
-Frank R. Rupert, P.G. 149

Abstract

Five short bottom sediment cores taken in Wakulla Spring Wakulla County, Florida, were described lithologically
and sampled for palynological study. Four of the cores were recoveredfrom sediments at the spring cave entrance
(130 feet water depth). One core was taken in a fossil vertebrate bone bed, 280 feet distance into the main spring
cave at a water depth of 240 feet. Sediments in the cores are composed of alternating intervals of quartz sand and
calcilitite, containing freshwater diatoms, freshwater mollusk shells and plant remains. The predominant pollen
present in all cores consists of a periporate variety typical of the herb families Chenopodiaceae and Amaranthaceae.
Arboreal flora, typical of the area surrounding the spring today, represent a very low percentage of tihe pollen
assemblage in the cores. Clustered Chenopod-Amaranth type pollen observed in one core suggest minimal transport
prior to deposition, and indicate that the bottom sediments in the cave may be essentially In situ. An absence of
exotic flora suggests a Quaternary age for the sediments.


Introduction

Wakulla Spring is a first-magnitude spring
situated in Wakulla County, Florida, about 15 miles
south of Tallahassee (Figure 1). Water flows from
a single vent into a large spring pool, approximately
100 feet wide and 200 feet long, which forms the
headwaters of the Wakulla River. The spring
discharges regional ground water from the Floridan
aquifer system.
The spring probably evolved from a large
post-Miocene sink which developed in the
Oligocene and Miocene limestones underlying the
area. Previous SCUBA explorations in the spring
revealed the presence of a large cave or passage
feeding the spring from depths in excess of 180 feet
below mean sea level (Olsen, 1958; Rosenau et al.,
1977). The cave typically measures about 40 feet
high and 80 feet wide. Pleistocene vertebrate
bones, charred wood, and numerous paleoindian
artifacts have been discovered in the outer 1100 feet
of the cave (Olsen, 1958). This led to speculation
that the cave may have been dry during glacial
periods of the Pleistocene.
During the last three months of 1987
fourteen cave divers, working under permit from the
State of Florida, conducted the most extensive
exploration of the Wakulla cave system ever
undertaken. This exploration revealed a sizable and
complex conduit system feeding Wakulla Spring.
Areas of the main cave were found to approach
sizes of 60 feet high and 120 feet wide. At a point
nearly 900 feet into the cave, the system splits into


four separate feeder conduits, one of which extends
over 4200 feet in from the cave entrance (Rupert
and Spencer, 1988; Stone, 1989).
As part of the scientific studies performed
during this project, the divers recovered a total of
seven short cave floor sediment cores ranging in
length from 9 inches to 31 inches. Five cores were
taken in the floor of the mouth of the main spring
cave; two others were recovered in a vertebrate
bone bed situated approximately 280 feet into the
main cave (Figure 1). Five of these seven cores,
representing four cave entrance cores and one
bone-bed core, are addressed in the present study.

Methods

The four cave-entrance sediment cores
were recovered using a one and one-half inch
diameter PVC pipe coring apparatus developed by
William Wilson of Subsurface Evaluations
Incorporated, Winter Springs, Florida (Figure 2).
The core tube was pushed into the bottom
sediments until it either bottomed against limestone
bedrock or reached the 36-inch core tube length
limit. The cohesiveness of the sediments generally
allowed the core to remain intact in the PVC barrel
as the coring device was withdrawn from the cave
floor sediments. In some cases the sediment
thickness exceeded 36 inches, but core recovery was
incomplete. The longest core recovered in this
.study was 31 inches. Two short cores taken inside
the cave in the outer bone bed were pushed into the
sediment until they bottomed against bedrock.

UNIVEftSITY OF FLORIDA LibARIES























































Figure 1. Wakulla Spring and core location map.


Figure 2. Diagram of 1.5 inch diameter PVC
sediment coring tube used in this study (Designed
and drafted by Willian l ilson, Subsurface
Evahtations, Inc., Wilter Springs, Florida).


; 1 i I




Lhreadd
3En Cap



STwo
_____ I I i.I. lT it
', '. .. ,



,~~~~~ ~~~ *-., -- .;" i


Be*1*J C-an) e -'


I1'*---


Lllj CJL'
"""'










Each core was extruded from the sampling tube
back on land by pushing a wad of paper towels
against the top of the sediment with a broomstick.
The cores were then scaled in polyethylene
wrapping.
The core packages were later opened and
each core was described lithologically. Lithologic
descriptions are provided in the Appendix section of
this report. Approximately 100 grams of sediment
was cut from selected intervals in the calcilutite
portions of five cores for pollen analysis. Only
intervals containing sufficient sediment to provide
the necessary 100 grams of sample were selected.
One sample was taken in each of Cores 1 through
4, and two samples were taken in Core 5. Table 1
includes the intervals sampled in each core. The
samples were then sent to the Delaware Geological
Survey in Newark for standard pollen-analysis
preparation and description. Results of this analysis
are shown in Table 1.
X-ray analysis was performed on one
sample from Core 2, taken in the vertebrate bone
bed within the main spring cave. This analysis was
conducted on a Phillips X-ray diffractometer housed
at the Florida State University Geology Department.
The calcilutite intervals in all cores were
spot-checked for the presence of diatoms, utilizing
temporary water-based smear slides with cover slips.
Three samples, comprised of one from Core 2 (4.5"
deep) and two from Core 5 (5" and 30" deep) were
permanently mounted for detailed diatom analysis.
Small portions of sample were disaggregated in
sodium hexametaphosphate solution, shaken, then
allowed to settle for 45 seconds. The supernatant
solution was then decanted, and the decanted
portion centrifuged to concentrate the suspended
diatoms. Standard smear slides were then prepared
from the centrifuge samples, using the aqueous
concentrate with a cover slip for the temporary
slides, and Norland Optical Adhesive as the
mounting medium for the permanent study slides.
Each of slides were scanned for diatoms, and the
various species were identified. The species present
are discussed in the results section.

Results

The Wakulla cave floor core sediments are
composed principally of medium to coarse grained
quartz sand and olive-gray, clay-like calcilutite. The
sand intervals contain freshwater gastropod shell
fragments (Helisoma sp.) and terrestrial and aquatic
plant remains. The calcilutite portions have the
appearance of siliciclastic clay when wet. These
intervals were found to contain partially
decomposed and unidentified plant remains, sand-
size limestone particles, and abundant diatom tests.


X-ray analysis of the calcilutite interval in Core
number 2 was performed to determine its
composition. This core was situated in one of the
vertebrate bone beds in the outer portion of the
main spring cave. The bulk of the sample is calcite,
with minor quartz and unidentified clay mineral
peaks. Much of this may represent fine breakdown
material from the limestone bedrock of the conduits
conveying groundwater to the spring.
Table 1 summarizes the major pollen
groups present in each of the samples. The
numbers shown in Table 1 indicate the percentages
of the total pollen sum represented by each pollen
type in the samples. A variety of pollen families
were present, including arboreal angiosperms,
conifers, herbs, ferns, and aquatic plants.
Dinoflagellates and cysts of green algae were also
present in Cores 1 and 2 in low abundance.
Interestingly, the dominant pollen present
in all the samples is that of the Chenopodiaceae and
Amaranthaceae, two plant families with
morphologically similar, periporate pollen grains. In
practice, pollen from the various genera in these
groups are indistinguishable. Therefore, they are
lumped together as "Chenopod/Amaranth" in this
report.
The Chenopodiaceae include as modern
representatives the glassworts and seablites. These
forms are characteristic salt marsh and salt flat
flora. The Amaranthaceae include both fresh and
brackish water swamp plants. Figure 3 illustrates a
Chenopodiaceae/Amaranthaccae pollen grain from
the Wakulla Spring sediments.


Figure 3. Chenopodiaceae/Amaranthaceae pollen
grain (modified from Erdtman, 1954, and based on
a photo by Dr. Johan Groot) X1000

The fossil Chenopod/Amaranth type pollen
comprised a minimum of 70 percent of the total
pollen assemblage (Core 3), and ranged up to 82
percent in Core 5, sample 1. Core 3 contained rare
pollen, with most belonging to the
Chenopod/Amaranth type. In Core 5, a group of 8
or 9 undispersed Chenopod/Amaranth pollen,
grouped as if in a pollen sac, were observed (Johan
Groot, personal communication). Since pollen is
generally dispersed rapidly after release, this would













Tuble 1. Pollen types present in the Wakulla Spring cores.


Interval Sampled

Anglosperms
Alnus (hazel alder)

Cadr (hickory)
Celts sugarberryy, hackberry)


Core 1
6-16.5"




P
P


Core 2 Core 3
0-9" 18-22"


P
5


Carpinus-Osrya (horn been, hop-hornbean)


Cynra (titi P
LiquidumoWr (swelgum) P
Nysse (tupelo. sourgum) P
SaOx (Wllow) 1
Ti/ia (basswood, linden) P
Ulmus (elm) 1 P
Ouercus (oak) 14 9
Conifers
Pinus (pine) 8 1
Herbs

Chenopodlaceae goosefoott family) 70 79
Composite (sunflower family) 2 P
Gramlnese (grass family) 1

Umbelllferae (carrot family) P
Aqualloc


-








W .....












IL


Core 4
5.25-12"




7






...-- .... --



...... ......
P

P
8
............. I.


5


71
2

P
P
*-11-1-,11, .....


Core 6
34.10.1" 23-31"



P
3 2
P

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


2 P
P P


1


4 11
...o.,........................





82 73
1 3

P
r12- -- -- -


Hydrocharitaceas (aquatic herbs) P
Sparganlum.Typha (cattail) 1 2 P 1


Fern


C

0


Poypodisceae (fe(r family) 4 3

yste of green alga P 2

lno(lagetlate P
........... .. .. ........... ..................................... .....~..........................


P indicates less than 1% of pollen total










Each core was extruded from the sampling tube
back on land by pushing a wad of paper towels
against the top of the sediment with a broomstick.
The cores were then scaled in polyethylene
wrapping.
The core packages were later opened and
each core was described lithologically. Lithologic
descriptions are provided in the Appendix section of
this report. Approximately 100 grams of sediment
was cut from selected intervals in the calcilutite
portions of five cores for pollen analysis. Only
intervals containing sufficient sediment to provide
the necessary 100 grams of sample were selected.
One sample was taken in each of Cores 1 through
4, and two samples were taken in Core 5. Table 1
includes the intervals sampled in each core. The
samples were then sent to the Delaware Geological
Survey in Newark for standard pollen-analysis
preparation and description. Results of this analysis
are shown in Table 1.
X-ray analysis was performed on one
sample from Core 2, taken in the vertebrate bone
bed within the main spring cave. This analysis was
conducted on a Phillips X-ray diffractometer housed
at the Florida State University Geology Department.
The calcilutite intervals in all cores were
spot-checked for the presence of diatoms, utilizing
temporary water-based smear slides with cover slips.
Three samples, comprised of one from Core 2 (4.5"
deep) and two from Core 5 (5" and 30" deep) were
permanently mounted for detailed diatom analysis.
Small portions of sample were disaggregated in
sodium hexametaphosphate solution, shaken, then
allowed to settle for 45 seconds. The supernatant
solution was then decanted, and the decanted
portion centrifuged to concentrate the suspended
diatoms. Standard smear slides were then prepared
from the centrifuge samples, using the aqueous
concentrate with a cover slip for the temporary
slides, and Norland Optical Adhesive as the
mounting medium for the permanent study slides.
Each of slides were scanned for diatoms, and the
various species were identified. The species present
are discussed in the results section.

Results

The Wakulla cave floor core sediments are
composed principally of medium to coarse grained
quartz sand and olive-gray, clay-like calcilutite. The
sand intervals contain freshwater gastropod shell
fragments (Helisoma sp.) and terrestrial and aquatic
plant remains. The calcilutite portions have the
appearance of siliciclastic clay when wet. These
intervals were found to contain partially
decomposed and unidentified plant remains, sand-
size limestone particles, and abundant diatom tests.


X-ray analysis of the calcilutite interval in Core
number 2 was performed to determine its
composition. This core was situated in one of the
vertebrate bone beds in the outer portion of the
main spring cave. The bulk of the sample is calcite,
with minor quartz and unidentified clay mineral
peaks. Much of this may represent fine breakdown
material from the limestone bedrock of the conduits
conveying groundwater to the spring.
Table 1 summarizes the major pollen
groups present in each of the samples. The
numbers shown in Table 1 indicate the percentages
of the total pollen sum represented by each pollen
type in the samples. A variety of pollen families
were present, including arboreal angiosperms,
conifers, herbs, ferns, and aquatic plants.
Dinoflagellates and cysts of green algae were also
present in Cores 1 and 2 in low abundance.
Interestingly, the dominant pollen present
in all the samples is that of the Chenopodiaceae and
Amaranthaceae, two plant families with
morphologically similar, periporate pollen grains. In
practice, pollen from the various genera in these
groups are indistinguishable. Therefore, they are
lumped together as "Chenopod/Amaranth" in this
report.
The Chenopodiaceae include as modern
representatives the glassworts and seablites. These
forms are characteristic salt marsh and salt flat
flora. The Amaranthaceae include both fresh and
brackish water swamp plants. Figure 3 illustrates a
Chenopodiaceae/Amaranthaccae pollen grain from
the Wakulla Spring sediments.


Figure 3. Chenopodiaceae/Amaranthaceae pollen
grain (modified from Erdtman, 1954, and based on
a photo by Dr. Johan Groot) X1000

The fossil Chenopod/Amaranth type pollen
comprised a minimum of 70 percent of the total
pollen assemblage (Core 3), and ranged up to 82
percent in Core 5, sample 1. Core 3 contained rare
pollen, with most belonging to the
Chenopod/Amaranth type. In Core 5, a group of 8
or 9 undispersed Chenopod/Amaranth pollen,
grouped as if in a pollen sac, were observed (Johan
Groot, personal communication). Since pollen is
generally dispersed rapidly after release, this would









suggest minimal transport of the pollen prior to
deposition.
Arboreal plant species comprise a
maximum of 14 percent of the pollen totals in any
sample. Most of the angiosperm tree and conifer
species typical of the modern forest surrounding
Wakulla Spring today are represented by only small
percentages of the fossil pollen in each sample.
Quercus (oak) ranges from 4 to 11 percent of the
totals. Caria (hickory), where present, ranged from
2 percent of the fossil pollen in Core 5, sample 2 to
a maximum of 7 percent in Core 4. Pinus (Pine)
comprises less than 1 percent in Core 6, and ranged
up to 8 percent in Core 1. The remaining plant
species comprise four percent or less of the pollen
assemblages in each sample. Core 3 contained only
rare pollen, and most of this was of
Chenopod/Amaranth. Green algae cysts were
present in Cores 1 and 2, and Dinoflagellates were
observed in Core 1.
The diatom species present, with the
exception of Paralia cf. sulcata (a brackish water to
marine species), are reported as common
constituents of modern fresh water bodies (United
States Department of the Interior, 1966). These
include Melosira italica, Gomphonema herculeana,
Epithema inegularis, Epithema ttgida, Navicula
amphibola, Cocconeis placentula, Navicula
cuspidata, Synedra ulna, and Pinnularia gibbia.

Discussion

The fossil pollen present in the Wakulla
Spring sediment cores provide insight into the
probable Late Pleistocene or Holocene history of
the spring. Of particular significance is the
overwhelming abundance of the
Chenopod/Amaranth pollen in all of the cores.
Due to the similarity of pollen from all genera of
the families Chenopodiaceae and Amaranthaceae,
it is usually not possible to differentiate the genera.
The Chenopodiaceae, or Goosefoot family,
are halophytic, and typically inhabit salt and
brackish marshes and flats. Three modern
indigenous genera of Chenopodiaceae occur in
Florida: Chenopodium, Suaeda and Salicomia
(Clewell, 1985). The genus Chenopodium can occur
in open inland areas, but also occurs along coastal
beach barrens (Clewell, 1981). Both Salicomia and
Suaeda are restricted to coastal salt marshes, salt
flats or, in some cases, fore-beach areas (Clewell,
1981, 1985),
TheAmaranthaceae are typically freshwater
swamp plants. One species, Amaranthus australis,
is abundant in Florida lakes today (Watts, 1969).


Watts (1969) suggested that the
Chenopod/Amaranth type pollen observed in lake
bottom cores from Marion County, Florida, may be
from this species. However, because pollen from
the two families is indistinguishable, a
paleoenvironmental interpretation is uncertain. The
questionable family affinity of the
Chenpod/Amaranth pollen in the Wakulla Cave
cores poses a problem in interpreting the
depositional environment of the cave floor
sediments. If the pollen is that of the Amaranths,
the sediments may simply be recent, freshwater
spring/marsh deposits. This is supported by the
presence of freshwater gastropod (Helisoma sp.)
shells and diatoms throughout the sediments in the
cores.
If the pollen are from the Chenopodiaceae,
a case may also be made for a brackish water
influence. Intuitively, one explanation for the
possible presence of Chenopodiaceae pollen in the
Wakulla Spring sediments is a marine transgression,
which would have shifted a coastal saltmarsh
environment landward to the present vicinity of
Wakulla Springs.
Two late Quaternary marine transgressions
are documented in the local geologic record. One
was the Late Pleistocene Pamlico sea level
(Sangamon Interglacial Period) highstand, which
stood approximately 25 feet above present sea level.
The Pamlico transgression corresponded to
an interglacial warm period, the Sangamon, which
pre-dates the most recent glacial period
(Wisconsinian) of the Pleistocene Epoch. Isotope
age dates from shell material collected in
elevationally-similar Pamlico terrace deposits on
Florida's east coast indicate sea level high stands
occurring at 130,000 and 85,000 years before present
(Osmond et al., 1965; 1970).
The Pamlico sea flooded large areas of
Florida, and inundated most of eastern Wakulla
County (Figure 4a). Many of the relict bars, dunes
and beach ridges shaping the surface of central and
eastern Wakulla County today were probably
associated with the Pamlico sea. The shoreline
likely fluctuated through time in an elevation range
of 10 to 25 feet above present sea level (MacNeil,
1950; Healy, 1975). This range placed the palco-
shoreline close to, and at times north of Wakulla
Spring, A saltmarsh environment, probably similar
to the modern marshes of southern Wakulla
County, could have fringed the Pamlico shore.



























Figure 4a. Approximate extent of the Pamlico
(Pleistocene) sea (modified from MacNeil, 1950;
Healy. 1975).


Figure 4b. Approximate extent of the Silver Bluff
(Holocene) sea (modified from MacNeil, 1950;
Healy, 1975).


While the age of formation of Wakulla
Spring is uncertain, present data suggest it was most
likely present and flowing freshwater during the
period in which the Chenopods grew nearby,
perhaps mixing with the Gulf waters and creating a
localized brackish environment in the Immediate
area of the spring. The paleo-freshwater flow in the
spring is evidenced by the very abundant freshwater
diatom assemblage contained within and intermixed
with the pollen in the core samples. The diatom
species present are common constituents of many
modern freshwater bodies (United States


Department of the Interior, 1966).
A second transgression of lesser magnitude.
possibly corresponding to the Silver Bluff Sea,
occurred in the middle Holocene, about 4,500 years
ago (Stapor and Tanner, 1977; Tanner et al., 1989).
This highstand is documented in beach deposits
along the panhandle coast of Florida. Beach ridge
and scarp elevation data and Carbop-14 dates on
associated archaeological artifacts from St. Vincent
Island (southwest of Wakulla Spring in Franklin
County, Florida) and adjacent mainland indicate this
highstand reached a height of about 5 feet above
modern sea level. Based on the modern
topography, a five-feet sea level rise would have
produced a marine transgression up the Waikul!a
River valley, reaching the spring, but being
restricted for the most part to the river valley itself
Figure 4b). Whether this transgression was
adequate to produce the inundation and water
salinity necessary to develop a salt marsh
environment around Wakulla Spring is uncertain.
The topography near Wakulla Spring today rises
rapidly from elevations of about 5 feet above mean
sea level immediately around the spring pool to
about 25 feet above mean sea level at the tons of
nearby gently-rolling sand hills. It appears unlikely
that such topography would have provided the
unobstructed saltwater interchange necessary to
maintain a saltmarsh environment.
Unfortunately, there are no age-dateable
materials associated with the Wakulla Spring
samples. The timing of such a transgression is
therefore uncertain. The pollen species present do
not provide a definitive age zone, but the absc-ce of
exotic floe- -llen in the core samples suggests a
Quatert ge for the cave floor sediments (Johan
Groot, personal communication). Additionally, in
light of the seemingly in-.place nature of the
sediments, it seems unlikely that shallow,
unconsolidated sediments such as these could
survive undisturbed in an actively flowing,
subaqueous, environment from a time earlier than
the late Quaternary.
A transition from a brackish salt flat
ecosystem to terrestrial forest is not documented in
the pollen record of the present samples. This may,
in part, be due to removal by erosion of portions of
the cave sediments. In addition, the large sample
interval required to obtain adequate quantities of
sediment for pollen analysis from the small
diameter cores taken in this study may have
obscured significant floral transitions. Future core
studies using larger diameter cores and smaller
sample intervals might better delineate temporal
pollen changes in the cave floor sediments.









suggest minimal transport of the pollen prior to
deposition.
Arboreal plant species comprise a
maximum of 14 percent of the pollen totals in any
sample. Most of the angiosperm tree and conifer
species typical of the modern forest surrounding
Wakulla Spring today are represented by only small
percentages of the fossil pollen in each sample.
Quercus (oak) ranges from 4 to 11 percent of the
totals. Caria (hickory), where present, ranged from
2 percent of the fossil pollen in Core 5, sample 2 to
a maximum of 7 percent in Core 4. Pinus (Pine)
comprises less than 1 percent in Core 6, and ranged
up to 8 percent in Core 1. The remaining plant
species comprise four percent or less of the pollen
assemblages in each sample. Core 3 contained only
rare pollen, and most of this was of
Chenopod/Amaranth. Green algae cysts were
present in Cores 1 and 2, and Dinoflagellates were
observed in Core 1.
The diatom species present, with the
exception of Paralia cf. sulcata (a brackish water to
marine species), are reported as common
constituents of modern fresh water bodies (United
States Department of the Interior, 1966). These
include Melosira italica, Gomphonema herculeana,
Epithema inegularis, Epithema ttgida, Navicula
amphibola, Cocconeis placentula, Navicula
cuspidata, Synedra ulna, and Pinnularia gibbia.

Discussion

The fossil pollen present in the Wakulla
Spring sediment cores provide insight into the
probable Late Pleistocene or Holocene history of
the spring. Of particular significance is the
overwhelming abundance of the
Chenopod/Amaranth pollen in all of the cores.
Due to the similarity of pollen from all genera of
the families Chenopodiaceae and Amaranthaceae,
it is usually not possible to differentiate the genera.
The Chenopodiaceae, or Goosefoot family,
are halophytic, and typically inhabit salt and
brackish marshes and flats. Three modern
indigenous genera of Chenopodiaceae occur in
Florida: Chenopodium, Suaeda and Salicomia
(Clewell, 1985). The genus Chenopodium can occur
in open inland areas, but also occurs along coastal
beach barrens (Clewell, 1981). Both Salicomia and
Suaeda are restricted to coastal salt marshes, salt
flats or, in some cases, fore-beach areas (Clewell,
1981, 1985),
TheAmaranthaceae are typically freshwater
swamp plants. One species, Amaranthus australis,
is abundant in Florida lakes today (Watts, 1969).


Watts (1969) suggested that the
Chenopod/Amaranth type pollen observed in lake
bottom cores from Marion County, Florida, may be
from this species. However, because pollen from
the two families is indistinguishable, a
paleoenvironmental interpretation is uncertain. The
questionable family affinity of the
Chenpod/Amaranth pollen in the Wakulla Cave
cores poses a problem in interpreting the
depositional environment of the cave floor
sediments. If the pollen is that of the Amaranths,
the sediments may simply be recent, freshwater
spring/marsh deposits. This is supported by the
presence of freshwater gastropod (Helisoma sp.)
shells and diatoms throughout the sediments in the
cores.
If the pollen are from the Chenopodiaceae,
a case may also be made for a brackish water
influence. Intuitively, one explanation for the
possible presence of Chenopodiaceae pollen in the
Wakulla Spring sediments is a marine transgression,
which would have shifted a coastal saltmarsh
environment landward to the present vicinity of
Wakulla Springs.
Two late Quaternary marine transgressions
are documented in the local geologic record. One
was the Late Pleistocene Pamlico sea level
(Sangamon Interglacial Period) highstand, which
stood approximately 25 feet above present sea level.
The Pamlico transgression corresponded to
an interglacial warm period, the Sangamon, which
pre-dates the most recent glacial period
(Wisconsinian) of the Pleistocene Epoch. Isotope
age dates from shell material collected in
elevationally-similar Pamlico terrace deposits on
Florida's east coast indicate sea level high stands
occurring at 130,000 and 85,000 years before present
(Osmond et al., 1965; 1970).
The Pamlico sea flooded large areas of
Florida, and inundated most of eastern Wakulla
County (Figure 4a). Many of the relict bars, dunes
and beach ridges shaping the surface of central and
eastern Wakulla County today were probably
associated with the Pamlico sea. The shoreline
likely fluctuated through time in an elevation range
of 10 to 25 feet above present sea level (MacNeil,
1950; Healy, 1975). This range placed the palco-
shoreline close to, and at times north of Wakulla
Spring, A saltmarsh environment, probably similar
to the modern marshes of southern Wakulla
County, could have fringed the Pamlico shore.










The Florida Geological Survey hopes to
continue this study with future acquisition of
additional sediment cores from Wakulla Spring
during the tentatively-scheduled 1992 Wakulla
Springs Expedition. In addition, similar sediment
cores may be obtained during concurrent studies in
Indian Spring, located one-mile northwest of
Wakulla Spring. Cores from an adjacent spring
should provide further insights on the extent, age,
and type of Quaternary paleoenvironmerits observed
in the Wakulla Spring area.

Acknowledgements

A number of individuals contributed their time
and expertise to make this study possible. Special
thanks are extended to Dr. Bill Stone and Mr. Wes
Skiles for incorporating the core sampling into the
1987 Wakulla Springs Exploration Project, and to the
Florida DNR Division of Recreation and Parks,
especially Mr. Ellison Hardee, Mr. Dana Bryan, and
Mr. Dick Miller for permitting the sediment coring on
State Park property. Mr. Bill Wilson coordinated the
cave mouth core sampling, lent his time and
specialized coring device to the collection effort, and
critically reviewed a draft of the manuscript. Mr.
Tom Morris assisted in collecting the cave-mouth
cores, and Mr. Wes Skiles and Mr. Fred Davis were
extremely helpfid in collecting the two cores from the
bone bed area within the main cave. Many thanks
are also due Dr. Johan Groot and the palynological
lab staff at the Delaware Geological Survey for the
preparation, examination, and interpretation of the
pollen assemblages in the core samples. The author
is gratefid to the following individuals for reviewing
drafts of this manuscript: Drs. Walter Schmidt and
Tom Scott, and Mr. Ed Lane of the Florida
Geological Survey, and Mr. Bill Bartodziej of the
FDNR, Bureau of Aquatic Plant Management.


References

Clewell, A.F., 1981, Natural setting and vegetation
of the Florida panhandle: A report
prepared under contract No. DACW01-77-
C-0104, U.S. Army Corps of Engineers,
Mobile, Alabama, 737 p.

Clewell, A.F., 1985, Guide to the vascular plants of
the Florida panhandle: Tallahassee, Florida
State University Press, p. 269-271.

Erdtman, G., 1954, An introduction to pollen
analysis: Waltham, Chronica Botanica
Company, 239 p.

Godfrey, R.K., and Woolen, J.W., 1981, Aquatic and
wetland plants of southeastern United
States: Athens, University of Georgia
Press, p. 93-101.


Healy, H.G., 1975. Terraces and shorelines of
Florida: Florida Bureau of Gcology Map
Series 71.

MacNeil, F.S.. 1950, Pleistocene shorelines in
Florida and Georgia: U.S. Geological
Survey Professional Paper 221-F, p. 95-107.

Olsen, S., 1958, The Wakulla Cave: Natural History,
v. 67, n. 7, p. 396-403.

Osmond, J.K., Car enter J.R., and Windom, H.L.,
1965, Th o/U234age of the Pleistocene
corals and oolites of Florida: Journal of
Geophysical Research, v. 70, n. 8, p.1843-
1847.

May, J.P., and Tanner, W.F., 1970, Age
of the Cape Kennedy barrier-and-lagoon
complex: Journal of Geophysical
Research, v. 75, n.2, p. 469-479.

Rosenau, J.C.. Faulkner, G.L., Hendry, C.W.. and
Hull, R.W.. 1977, Springs of Florida:
Florida Bureau of Geology Bulletin 31
(revised), p. 415-424..

Rupert, F.R., and Spencer, S. M., 1988, The geology
of Wakulla County, Florida: Florida
Geological Survey Bulletin 60, 46 p.

Stapor, F.W., and Tanner, W.F., 1977, Late
Holocene mean sea level data from St.
Vincent Island and the shape of the late
Holocene mean sea level curve: in:
Proceedings, Coastal Sedimentology
Symposium, Florida State University,
Department of Geology, p. 35-68.

Stone, W.C. (ed.), 1989, The Wakulla Springs
Project: Austin, Raines Graphics, 212 p.

Tanner, W.F., Demirpolat, S., and Alvarez, L., 1989,
The "Gulf of Mexico" Late Holocene sea
level curve: Transactions-Gulf Coast
Association of Geological Societies, v. 39,
p.553-562.

United States Department of the Interior, 1966, A
guide to the common diatoms at water
pollution surveillance system stations:
Federal Water Pollution Control
Administration, Water Pollution
Surveillance, 1014 Broadway, Cincinnati,
OH, 45202, June, 1966, 101 p.

Watts, W.A., 1969, A pollen diagram from Mud
Lake, Marion County, north-central
Florida: Geological Society of America
SBulletin, v. 80, p.631-642.


S7.










The Florida Geological Survey hopes to
continue this study with future acquisition of
additional sediment cores from Wakulla Spring
during the tentatively-scheduled 1992 Wakulla
Springs Expedition. In addition, similar sediment
cores may be obtained during concurrent studies in
Indian Spring, located one-mile northwest of
Wakulla Spring. Cores from an adjacent spring
should provide further insights on the extent, age,
and type of Quaternary paleoenvironmerits observed
in the Wakulla Spring area.

Acknowledgements

A number of individuals contributed their time
and expertise to make this study possible. Special
thanks are extended to Dr. Bill Stone and Mr. Wes
Skiles for incorporating the core sampling into the
1987 Wakulla Springs Exploration Project, and to the
Florida DNR Division of Recreation and Parks,
especially Mr. Ellison Hardee, Mr. Dana Bryan, and
Mr. Dick Miller for permitting the sediment coring on
State Park property. Mr. Bill Wilson coordinated the
cave mouth core sampling, lent his time and
specialized coring device to the collection effort, and
critically reviewed a draft of the manuscript. Mr.
Tom Morris assisted in collecting the cave-mouth
cores, and Mr. Wes Skiles and Mr. Fred Davis were
extremely helpfid in collecting the two cores from the
bone bed area within the main cave. Many thanks
are also due Dr. Johan Groot and the palynological
lab staff at the Delaware Geological Survey for the
preparation, examination, and interpretation of the
pollen assemblages in the core samples. The author
is gratefid to the following individuals for reviewing
drafts of this manuscript: Drs. Walter Schmidt and
Tom Scott, and Mr. Ed Lane of the Florida
Geological Survey, and Mr. Bill Bartodziej of the
FDNR, Bureau of Aquatic Plant Management.


References

Clewell, A.F., 1981, Natural setting and vegetation
of the Florida panhandle: A report
prepared under contract No. DACW01-77-
C-0104, U.S. Army Corps of Engineers,
Mobile, Alabama, 737 p.

Clewell, A.F., 1985, Guide to the vascular plants of
the Florida panhandle: Tallahassee, Florida
State University Press, p. 269-271.

Erdtman, G., 1954, An introduction to pollen
analysis: Waltham, Chronica Botanica
Company, 239 p.

Godfrey, R.K., and Woolen, J.W., 1981, Aquatic and
wetland plants of southeastern United
States: Athens, University of Georgia
Press, p. 93-101.


Healy, H.G., 1975. Terraces and shorelines of
Florida: Florida Bureau of Gcology Map
Series 71.

MacNeil, F.S.. 1950, Pleistocene shorelines in
Florida and Georgia: U.S. Geological
Survey Professional Paper 221-F, p. 95-107.

Olsen, S., 1958, The Wakulla Cave: Natural History,
v. 67, n. 7, p. 396-403.

Osmond, J.K., Car enter J.R., and Windom, H.L.,
1965, Th o/U234age of the Pleistocene
corals and oolites of Florida: Journal of
Geophysical Research, v. 70, n. 8, p.1843-
1847.

May, J.P., and Tanner, W.F., 1970, Age
of the Cape Kennedy barrier-and-lagoon
complex: Journal of Geophysical
Research, v. 75, n.2, p. 469-479.

Rosenau, J.C.. Faulkner, G.L., Hendry, C.W.. and
Hull, R.W.. 1977, Springs of Florida:
Florida Bureau of Geology Bulletin 31
(revised), p. 415-424..

Rupert, F.R., and Spencer, S. M., 1988, The geology
of Wakulla County, Florida: Florida
Geological Survey Bulletin 60, 46 p.

Stapor, F.W., and Tanner, W.F., 1977, Late
Holocene mean sea level data from St.
Vincent Island and the shape of the late
Holocene mean sea level curve: in:
Proceedings, Coastal Sedimentology
Symposium, Florida State University,
Department of Geology, p. 35-68.

Stone, W.C. (ed.), 1989, The Wakulla Springs
Project: Austin, Raines Graphics, 212 p.

Tanner, W.F., Demirpolat, S., and Alvarez, L., 1989,
The "Gulf of Mexico" Late Holocene sea
level curve: Transactions-Gulf Coast
Association of Geological Societies, v. 39,
p.553-562.

United States Department of the Interior, 1966, A
guide to the common diatoms at water
pollution surveillance system stations:
Federal Water Pollution Control
Administration, Water Pollution
Surveillance, 1014 Broadway, Cincinnati,
OH, 45202, June, 1966, 101 p.

Watts, W.A., 1969, A pollen diagram from Mud
Lake, Marion County, north-central
Florida: Geological Society of America
SBulletin, v. 80, p.631-642.


S7.








APPENDIX


Lilhologic descriptions of cave floor sediment cores
II I I Ia


Water Depth: 140 feet (42.6 m)
Length: 16.5 in. (41.2 cm)
Collected by William Wilson, 11-14-87.


Lithologic Description:


Lithology:


0.0-3.3 in. k0.0-8.6 cm)



3.3-5.6 in. (S.4-14.2 cm)



5.(-12.0 in. (14.2-30.5 cm)



12.0-13.1 in. (30.5-33.3 cm)


13.1-16.5 in. (33.3-41.2 cm)


Dusky yellowish brown (10YR 2/2) organic-rich calcilutite, containing
abundant brown plant remains and freshwater gastropod (Helisoma sp.) shell
fragments.

Olive gray (5Y 4/1) organic rich calcilutite, containing abundant plant
remains, shell fragments, and limestone fragments. Interval 5.4-5.6 in.
composed of matted brown plant remains intermixed with calcilutite.

Dusky yellowish brown (10YR 2/2) organic rich calcilutite, containing
abundant plant remains, wood fragments, and limestone and freshwater
gastropod shell fragments.

Olive gray (5Y 4/1), organic rich, fine to medium quartz sand, containing
freshwater shell fragments.

Dusky yellowish brown (10 YR 2/2), organic rich calcilutite, containing
limestone granules, freshwater shell fragments, and diatoms.


. llti H .11 .J.,* ,A*...i4Fil....A. td*^.... 4 ''


Core 2 Water Depth: 195 feet (59.4 m)
Length: 9.5 in. (24.1 cm)
Collected by Fred Davis, 12-28-87, in vertebrate bone bed,
285 feet inside cave.


0.0-9.5 in. (0.0-24.1 cm)


Brownish gray (5 YR 4/1) organic rich calcilutite, containing limestone
fragments, plant remains, and freshwater gastropod shell fragments. Thin
laminate of matted plant remains alternating with calcilutite in interval 4.0-9.5
in. (10.2-24.1 cm).


Core 3 Water Depth: 140 feet (42.7 m)
Length: 23.1 in. (58.7 cm)
Collected by William Wilson, 11-15-87.


0.0-13.5 in. (0.0-34.3 cm)


Dusky yellowish brown (10YR 2/2) organic rich calcilutite, containing
abundant plant remains, limestone particles, and rare ostracode shells.
(continued on next page)


Core I


Depth:







Core 3, continued:


13.5-15.3 in. (34.3-38.7 cm)



15.3-17.8 in. (38.7-45.2 cm)

17.8-21.5 in. (45.2-54.6 cm)



21.5-23.1 in (54.6-58.7 cm)


Core 4


Yellowish gray (5Y 8/1), fine to medium quartz sand containing plant remains.
Bedding in core angled approximately 450 to the horizontal; probably a slope
deposit.

Olive black (5Y 2/1) calcilutite containing abundant plant remains.

Yellowish gray (5Y 8/1), fine to medium quartz sand, with interbedded
calcilutite, and containing plant remains, limestone particles, and reworked
Oligocene foraminifera.

White (N9) to yellowish gray (5Y 8/1) calcarenitic limestone, containing
abundant Oligocene foraminifera (Core bottomed on Suwannee Limestone).


Water Depth: 140 feet (42.7 m)
Length: 24.1 in (61.2 cm)
Collected by William Wilson, 11-15-87.


0.0-4.3 in. (0.0-10.9 cm)




4.3-12.4 in. (10.9-31.5 cm)


12.4-17.5 in. (31.3-44.5 cm)


17.5-24.1 in. (44.5-61.2 cm)


Dark yellowish brown (10YR 4/2), very fine quartz sand, containing abundant
freshwater gastropod shells, shell fragments, limestone particles, and organic.
Mollusk shell hash intervals present between .5 and 2.0 in. (1.3-5.1 cm) and
between 3.3 and 4.1 in. (8.4 and 10.4 cm).

Dark yellowish brown (10YR 4/2), unconsolidated organic rich calcilutite,
containing approximately 10% very fine to fine quartz sand.

Yellowish gray (5Y 8/1), fine to medium quartz sand, containing mollusk shell
fragments, limestones fragments, and organic.

Pale yellowish brown (10YR 6/2), very fine to fine quartz sand with calcilutite
matrix. Contains mollusk shell and limestone fragments, abundant plant
remains, and well-preserved Oligocene Suwannee Limestone foraminifera
eroded from underlying limestone.


Core 5 Water Depth: 135 feet (41.2 m)
Length: 31 in. (78.7 cm)
Collected by William Wilson, 1987.

0.0-31.0 in. (0.0-78.7 cm) Dark yellowish brown (10YR 4/2) to dusky yellowish brown (10YR
2/2), organic rich calcilutite, containing abundant plant remains and limestone
particles. Abundant diatoms at 10.0 in. (25.4 cm).



Note: Color designation codes are taken from The Rock-Color Chart Committee, 1984, Rock-Color Chart:
Geological Society of America, P.O. Box 9140, Boulder, CO, 80301.


~"~;ki~i~"~T;~I~~'~-"~j3~~LSS~~










FLRD GEOLOSk ( IC SUfRiW


COPYRIGHT NOTICE
[year of publication as printed] Florida Geological Survey [source text]


The Florida Geological Survey holds all rights to the source text of
this electronic resource on behalf of the State of Florida. The
Florida Geological Survey shall be considered the copyright holder
for the text of this publication.

Under the Statutes of the State of Florida (FS 257.05; 257.105, and
377.075), the Florida Geologic Survey (Tallahassee, FL), publisher of
the Florida Geologic Survey, as a division of state government,
makes its documents public (i.e., published) and extends to the
state's official agencies and libraries, including the University of
Florida's Smathers Libraries, rights of reproduction.

The Florida Geological Survey has made its publications available to
the University of Florida, on behalf of the State University System of
Florida, for the purpose of digitization and Internet distribution.

The Florida Geological Survey reserves all rights to its publications.
All uses, excluding those made under "fair use" provisions of U.S.
copyright legislation (U.S. Code, Title 17, Section 107), are
restricted. Contact the Florida Geological Survey for additional
information and permissions.