PROCEEDINGS
OF THE FIRST SYMPOSIUM
ON THE GEOLOGY
OF THE BAHAMAS
MARCH 23--25, 1982
FLO R I OA
.......
CAY . SAL "
SliNK
' •••• ~O (>
..... ,;
College Center of the Finger Lakes
Bahamas Field Station
San Salvador, Bahamas
HOLOCENE LITHIFICATION OF CARBONATE SEDIMENTS,
SAN SALVADOR ISLAND, BAHAMAS
Donald E. Hattin
Department of Geology
Indiana university
Bloomington, IN 47405
San
Salvador
Island is one of the world's finest natura l
laboratories
for observation and study of lithification processes
in
carbonate
Ho l ocene
beach,
lagoon,
localities ,
This
which
is
a
wealth of opportunities for research.
were examined during the March, 1982, field conference, and
as
instructors
who
transport,
of
origin
guide
offer
Pristine
the
combine
a
for
future
courses
vis itors
concerned
with
as
\fel l as for
the genera tion ,
deposition and lithif icat i on of the island's carbonate
sediments.
have
offer
inc ludes a summary of lithification phenomena, most of
intended
size
Examp l es of ongo ing subtida l ,
and dune lithification are ev i dent at many island
and
note
sediments.
to
island,
make
and
quality
and
easy
the modern environments, sma ll
access
to
the described sites
San Salvador an ideal place for researching the
stratigraphic
undergone
of
significance
lithification
in
of carbonate bodies that
recent times.
All p l ace names
used in this summary are shown on the index map.
Beachrock
Holocene
environments
at
CCFL
directly
Fernandez
stretch
beachrock
is
a
of San Salvador.
major feature in the shore line
Consp icuous examples include those
Beach, the south shore of Rice Bay, the beach area l y ing
to
the
Bay.
of
northeast
of
Rocky
Point,
and
the shore of
At CCFL Beach the rock is developed along a 490 m
shoreline
that
extends
45
eastward
from
the
CCFL
launching
mostly
ramps
colored
intertidal
suggestive
rock
algae
such
well-preserved
of
CCFL
and
the
clean,
buried
beachrock
has
as
1951),
is
bolts,
drive
chains,
fragments of mil k glass, and even a
cannonball
(Fig.
2).
At
the inner
beachrock exposure are scattered, loose
loosely
in
Stephenson,
Howeve r , cemented into the
artifacts
iron
Collectively,
sand.
(Stephenson
bottles,
of
is well cemented, and is
hardness and coloration, which is caused
modern
cast
edge
partially
rock
of considerable antiquity.
carbonated-beverage
slabs
The
or black according to position within the
Rock
of
are
( landward)
1) •
yellow
zone.
growths
by
(Fig.
cemented
similarly
carbonate
textured,
sand
that
lie
noncemented foreshore
the foregoing observations suggest that the
been
cemented
in
very recent times and is
continuing at present.
The
to
CCFL beachrock dips seaward at an angle corresponding
seaward
high
meter
slope
of
the
present foreshore surface.
At normal
tide the landward edge of the main beachrock exposure lies a
or
two
the
rock
is
has
occurred
backwash
offshore,
barely
in
of
a
and the topographically highest part of
awash .
Apparent l y, beachrock lithification
progressive l y
storm
waves
has
landward
eroded
the
direction,
landward
and the
edges
of
beachrock beds so as to form low, landward-facing scarps.
The
conspicuous
and
beachrock
numbers
mollusks.
crystals
presumed
grains are predominantly lithoclasts, with
of
grains
Isopachous
to
be
derived from algae, foraminife rs
cement,
aragonite,
interstices of this highly porous rock.
46
consisting
fi lls
only
of
needle-like
partial l y the
F i g . 1:
Exposure of Ho l ocene beachrocl< at CCFL Beach.
Loose
b locl<s of beachro cl< o n
l andward s i de of exposure
cou l d become inco r po rated
i nto any new beachrocl<
that. may for m here.
Fig. 2:
Exposu re of Ho locene beachroc l< a t CCFL Bea ch, show i ng
cannonba ll that 'vas a l most
complete l y enc l o s ed by we lllithified r ocl< befo r e exca vation.
Fi g . 3 :
Exposure of Holocene beachrocl< on beach sho rtly to the
northeast of Rocky Po i nt .
Note beachrocl< cobb l e (C)
enclosed in beachrocl< bou l der
(B) that i s , i n turn, incor po rated within the l ates t
gene r ation of beachrocl< ( A ).
47
The
body
of
landward
beachrock ,
hole-riddled,
that
l i es
(1951),
this
within
cliff
is
thinly
and
norma l
edge
of
CCFL
ma rked
bedded,
the
gray
beach, adjacent to the main
by
a
low
gently
zone
cli ff
he l d
seaward-dipp i ng
of
h i gh
between
one
an~
tides,
limestone
Stephenson and Stephenson
consists of sand-sized carbonate grains.
lies
up by a
The top of
and two meters above the level of
wou l d
seem
to
be l o n g to an eleva ted,
Pleistocene beach facies.
Interp retati on
of
this holey, c lif f-fo r mi ng li mesto ne is
c l arified
by comparison with a s i mila r cliff t hat faces the beach
extending
northeastward
hi gh-energy
The
app r oximate l y
for
on
its
excess
as
to
10
s lopes
of
one
bou l ders,
mete r
3).
(Fig.
beachrock
seaward
degrees--the
adjo ining foreshore.
content
of
repeated
bea chrock
6
the
beachrock
At this locality, the
beach is associated with an i mpressive deve lopment of
beachrock.
sands
from Rocky Poi nt .
and
The
entire
development
an
ang l e
of
same as for unconsolidated
This beachrock is remar kable
which
were
at
reach
de ri ved
maximum lengths in
from
ea rlier-formed
complex comp ri ses evi denc e of
and dis rup tion by sto r ms.
Here,
at CCFL Beach , the beach is bo r dered landward by a low coastal
c li ff
that
bedded,
comprises a 2 meter thickness of hole-riddled, thinly
seaward l y
li mestone
consists
however,
the
be t ween
limestone
ca r bonate
ang l e
d i pping
sand
of
limestone.
sand- sized
As
at
CCFL
ca r bonate
Beach, the
gra ins.
He r e,
limestone cliff is discontinuous, and the inte rvals
that
corresponding
exposures
are
filled
wi th
mos tl y
loose
i s thin l y laminated, with seaward dip at an
to that of the adjacen t limestone (Fig. 4).
48
VARIATION OF CERION POPULATIONS
ON SAN SALVADOR
Jane Rose
Department of Geology
Univeristy of Rochester
Rochester, NY 14607
cerion
the
sole
divided
valid
of
is
genus
into
present
is
the
the
of West Indian pulmonate land snail,
family
than
600
Cerionidae.
named
The genus has been
entities, but the number of
unknown (Mayr and Rosen, 1956).
species
at
genus
of
more
species
named
a
The profusion
has resulted from the high degree of variat ion
species
variation
l evel.
Investigations
concerning the
causes
of
in Cerion populations were conducted by the
author
during 1979 and 1980 at the CCFL Bahamian Field Station on
the island of San Salvador in the Bahamas.
San
Salvador
1)
Data
collected
and
(Fig.
variation
factors,
supports
many local populations of Cerion.
on shell structure in thirty populat i ons has been
analyzed,
statistically
between
the
local
demonstrating
populations
is
that
significant.
Two
predation and sandblasting, were observed which may help
to explain popu l ation variability in cerion.
Land
1978).
cardisoma
crabs
are
known
Predation
of
Cerion
is
intense
important
selective
individual
populations.
cerion
shells
It
thought
is
appear
on
San
force
The
to
prey
upon
populations
Salvador
resulting
jagged
Cerion (Woodruff,
by
the
land
crab
and is thought to be an
in
holes
variation
between
on opposing side of
to be the result of damage by land crabs.
that the snail is gripped by one claw of the land
4?
Fi g. /]:
Same loc al it.y as Fig. 3, showing
storm- beach deposits. A, Highlevel beach sands formed by de posit.ion during fairly recent
st.orm(s). D, Lithified, highlevel beach sands deposited by
more ancient. Holocene st.o r m(s)
and now cemented int.o cliff forming limest.one.
Note accord ance of uppermost surfaces of
limestone and recent sand. No t.e
also that. the most. recent stormbeach sands show initial stages
of cementation (C).
Fig. 5:
Cul tura ll y modified conch
in c li ff - fo r mi ng, stormbeach limestone a t. Barl~er' s
Point. P r esence of such
conchs at.t.est.s yout.hfu l
age of thi s rock, ,rhich
has been dat.ed as 80 years
B.P. by the radiocarbon
met.hod. Ho l e (arrOl') in
conch is man made.
Fig. 6:
Eo lianit.e exposure at
coastal reentrant O.G
krn nort.h of East. Beach
access road from Unit.ed
Estates. Rock in lower
part of exposure is
better cement.ed than
that above. 2\t. higher
leve ls, roclc crumbles
readily to form loose
sand (a r rOlJ) •
50
youthful
year
age
B.P.
the
of
rock, which yields a radiocarbon age of 80
1981) .
(Stipp,
This
rock
apparently originated by
lithification of a gravelly storm-beach sand in near-recent time.
Beachrock,
or
by
whether
lithification
numerous
problems.
of
formed
in the fair weather foreshore
higher-level,
storm-beach sands, poses
What triggers the lithification process?
Why
are
some beaches characterized by extensive beachrock development
and
others
are
evaporation
a
Is
and
essentially
there
the
lithification
the
cement
derived
primarily
from
To what extent is percolating rainwater
a
relationship
flow
of
between
groundwater
occurrences
towards the sea?
of
Does
occur sporadically, or is the lithification process
continuous?
How
Has
extend?
beachrock
gradually
Is
of seawater?
factor?
beachrock
sea
not?
far
seaward
beachrock
do
formation
the
blankets of
proceeded
in
a
shoreward direction during the post-Wisconsinan rise of
These
level?
and
related questions are the grist for much
future research on San Salvador beachrock deposits.
Dunes
The
efficacy
lithification
coastal
of
cliff
approximately
of
kilometer
eastward
from
eolian
carbonate
sands
much
better
stratigraphic
Furthermore,
near
situated
0.6
spray
sands
coastal
leading
are
salt
a
factor
in Holocene
is illustrated very well in the
the
north
United
as
north
of
Estates.
end
the
of
beach
Here,
the
East
access
Beach,
road
lower-most
that are exposed in a coastal promontory
cemented
than
eolian
sands lying in the same
position in an adjacent coastal reentrant (Fig. 6).
partially lithified dune sands extend farther up the
51
coastal
cliff
the promontory than in the coastal reentrant.
differences
These
apparently
by
at
salt
in
degree
to
differences in degree of sediment wetting
rocks
of the promontory being wetted mo re often
related
spray,
of
eolianite
lithification
are
and
more thoroughly than sands of the coastal reentrant.
Support
for
the
in
salt-spray
distance
into
coastal
reentrant ,
extending
be
noncemented
eolian
little
sands
sands
are
is
evident
that sands have been cemented.
cementation
with
a
is
largely
vegetated,
the
beach
effect
shovel
At
within .
are
no
mechanism
the
but
so
as
top
are
of
on lithification.
i.e.,
This crust can
to
expose mostly
the dune ridge the
nonlithified.
(approximat e ly
the
In the
surficial,
a few centimeters into the cliff.
above
or
cliff
readily
sands
distance
the
only
dislodged
cementation
10
At
this
m) salt spray has
At North Point the dune
general ly well cemented , which may be owing largely to
exposure of the peninsula to salt spray.
The
hypothesis
evaporation
of
rain
play
water
nature
now
lying
Pigeon
they
of
the
at
Creek
forming
salt
of
coastal
spray
needs
dune - sand
testing.
lithification
Does perco l ation of
a significant role in cementation?
cement?
by
What is the
Are the weakly cemented crusts on dunes
inland locations, such as between the north end of
and
the
present
today?
These
east coast, relict crusts or are
and
other
quest ions
regarding
lithification of dune deposits are worthy of investigation.
Sto rm Gravel
At
Government
the
westernmost
edge
of
French
Bay Beach, west of
Dock, cliff-forming , Pleistocene eolianite is overlain
52
locally
by
conglomerate
brittle
and
(Fig.
crust
the
of
movement
as
of
terrain
into
a
talus
(My l orie,
conglomerate
rounded
cobble
is
and
mant l ed
boulde r
by a hard,
is sharp.
deposit
The cong l omerate has been
that
resulted
from downs l op e
fragments derived from erosion of a kars tic
However, limestone c obb l e s
karst terrains are normally solution scul p t u r ed
range
of
l imestone
shapes
of
eolianite
oral comm., 1982).
in
wide
a
veneer
and contact between the conglome r ate
eolianite
bed r ock
boulders
The
7).
caliche,
crusted
interp r eted
and
well-cemented
a
of
commonl y
clasts
the
so r t
bizarre
range
shapes.
generally
In
t hi s
from angu l ar t o
that might result from eros i on and
transport in a high-energy environment.
A
studi ed
(by
on
way
Here,
reasonable analog of the French Bay cong l omerate c an be
the
of
Queen's
is
beneath
a
recent
mostly
composed
of
are
from
limestone,
been
storm
together,
with
cobble-sized limestone clasts.
lime
grainstone
depos i ted
scattered
entire
coated
a reddish brown
gravel consisting of subangular to we l l
and
and
mass
and
conglomerate
These c l asts a r e
are light co l ored, i.e., t hey
recently and have not yet become d i s colo red
weathering or algal infestation.
exposu re,
the turnoff to Dump Point.
exposed in the intertidal zone and disappears landwa r d
rounded,
have
Highway)
(?)
Pl eistocene
crust,
by
north shore of San Sa l vador, exactly 1.1 km west
ac r oss
the
A few of these mode r n c l a st s
land"ard
side of the crusted bed r ock
are cemented firmly to the crust (Fig. 8).
of
to
would
storm-gravel
the
clasts
underlying
result.
was
bedrock,
to
a
become
If the
cemented
limestone- cobb l e
Such a conglomerate body wou l d have
53
Fig. 7:
Poor ly so rted, pebb l y
co bb ly bou l der cong l o merate near eas t end
of l ow coasta l c li ff
at Fr ench Day. No t e
we ll r ou nded c last s
near man ' s hand (arrow).
Fig. 8:
Cobbles of gravel gene r ated
by recent s t orms at i nner
edge . of bea c h, 1.1 kr-l
west of turnoff l eading to
Dump Point . Clas t s a r e
cemen t ed f irml y to under l y ing caliche- li J(e c r ust
on P l e i stocene bedrock.
Fi g . 9 :
Thi n l y bedded li mes t one
slab from short. l y be nea t h sed i men t-Iva ter
in terface in southl·!es t
end of P i geon Cr eek l agoon.
54
an
appearance
Bay,
and
that
would
is
have
essentially
identical to that at Fr ench
an identical stratigraphic relationship to
the underlying crusted limestone.
Several
questions attend interpretation of the French Bay
cong l omerate.
Is
the
At what time in history was the grave l deposited?
elevation
levels
suggested
CocJ<burntown
eolianite
facies
the
above
by
present sea level compatab l e with water
upper
(Sangamonian)
(suggesting
(suggesting
nature
of
reefs?
of
the
Grotto
Beach
or
Were the clasts derived from
downs l ope transport) or subtidal and beach
marine
the
surfaces
erosion and wave transport)?
cementing
substance?
Are
What i s
clast
shapes
compatable with the talus or with the storm-gravel hypothesis?
Lagoonal Limestone
southwestern end of Pigeon Creek, where the lagoon i s
The
most
approached
are
that
mangrove.
At
fringed
carbonate
clear
gelatinous
several
h igh - sp ired
most
obvious
reach
the
a
Columbus
Landings paved road,
and
dotted
with
dense grm,ths of red
sand
is
genera
skeletal
of
and
admixed
The
material.
gast ropods,
maximum
that
coarser
carbonate
foramin ifera,
minute
constituent
diameter
with carbonate mud and
to
particles
ostracodes,
sma ll
thin- shelled b i va lves .
is
The
peneroplid forams, which
of several mi ll imeters and produce in
sediment a cha r acter i st i c white-speckled appearance.
beneath
as
the
this locality lagoonal sediment consists of poor l y
sorted
inClude
by
large open expanses of shallow water, less than 1 meter
comprises
deep,
closely
Shortly
this surficial material the sed iment has been cemented so
form
an
extensive
sheet
55
of
crumbly
limestone that i s
distinctly
(Fig.
bedded
9).
The
the
and
reaches
rock
in
fine-
grains
are
and/or
altered ooliths.
forams
and
cement
comprises
highly
to
a
dark
and
sand
may
range.
Host of the
be large l y fecal pellets
Skeletal grains were derived mainly from
and
an
many
have
isopachous
porous.
white
coloration,
and
a micritic envelope.
fringe
of
The
minute, needle - like
Although most grains have been bleached
color ,
some of the ostracod va l ves retain a
suggesting
that
there
Lithification
sediment.
of 3 to 4 cm
the aragonite habit, but c ementation is weak and the
nearly
recently
very-coarse
peloids
molluscs,
rock
is
to
micritic
of
thickness
is a poorly sorted grainstone, with gra i ns
mostly
crystals
max imum
that
lithification
has
occurred
has
been no subaerial exposure o f the
only
of the near surface sediment a l so
suggests that cementation is a recent phenomenon.
The
deta iled
origin
study.
radiation,
oral
and
comm.,
of
may
salinity
at
High
initial
of
factors
water
pumping
sediment,
would
could
with
described
by
questions
remain .
where
that
facilitate
affect
(Hi tchell,
the lagoonal
the
only
development
reducing permeability.
Shinn
suggest
0/00
flow
of
through the original sediment by tidal
gradually
places
a problem in need of
be supersaturated with calcium carbonate.
porosity
Such
centimeters
is
reaches a maximum of 42
These
times
carbonate-saturated
pump ing.
limestone
Wa ters of the lagoon are easily warmed by so l ar
1982).
waters
this
of
the
upper
few
cement crys t a l s
Persian Gulf marine cementation
(1969) is a reasonably good ana log, but many
How
cementation
extensive
has
is this limestone?
affected
56
any
Are there
of the more deep l y
buried
sediments?
still
in
salinity
When
progress?
or
limestones
t i da l
have
did
cementation occu r ?
Under
what
cond i tions
Is cementation
of
tempe rature,
action did the lithification occur?
an
origin
in
Do these
common with those of hypersa line
Storr ' s Lake (Teete r, oral corom., 1982).
Stromatolites
mats
Al gal
environments
·of
low
caps
l evels.
organic-rich
spells
adjacent
the
po l ygona l
common
phenomenon
in
lacustrine
of San Salvador , and are especially evident at times
water
di r ectly
a
are
Fo r
carbonate
examp l e, a thick, rubbery alga l mat
sediments
in
a
lake
to Qu een's Highway at Rocky Point.
a l ga l
that
li es
During dry
mat is expo s ed to air and becomes disrupted by
patterns
of
dessica ti on
cra cks that are readily seen
from the paved ro ad.
Al gal
sho re
are
of
mats
Storr 's Lake.
expo s ed
surfaces .
unconso li dated,
However,
and
at
approaches
the
the
(Fig.
laminated,
fine
are
togeth e r
as
These
examples
extensively along the we stern
During low-water stand s ma n y of t he mats
Most
of
laminations
northernmost
the
are
unde rlying
sediment
is
at best poorly developed.
place
where
Queen's
Highway
lake cl osely , a l ga l mats are associat ed with true
s tromato lites
bound
developed
to the atmosphere and sh rive l so as to form lumpy or
mamm ilated
much
are
10).
These
structures
compr ise
crudely
sand- t o fine grave l- sized carbonat e gra ins t ha t
to
form crumbly limestone knobs that are as
15 to 20 cm in diameter and 12 to 15 cm tall (Fig. 11).
are
yet
true
columnar
d i scovered
in
stromato li tes--pe rhaps
the
57
the
finest
Caribbean/Bahamas region.
The
Fig. 10:
West Side of Storr's Lake,
showing eme r gent crests
of co lumnar stromatolites
that are enc rusted by
living a l ga mats.
Fig. 11:
Side view of modern stromatolite from west side of
Sto rr 's Lake, shOl{ing irregularly columnar shape.
Ar r ow indicates crust composed of nearly white,
we ll-cemented, very fine - grained calcitic limestone
mentioned in text. Photo by George R. Ringer.
stromatol ites
of
whi ch
compr i ses
Assoc iated
nearly
with
whi te,
beneath
the
are capped by a gelatinous algal mat, at l east part
the
there
fo r ms
very
was
side
a
filaments resemb ling Lyngbya.
stromatoli te
illustrated in Figure 11 is a
well cemented carbonate crust, which extends
stromatolite
structure
a l ong
the
very
the
thread-li ke
and
apparent l y formed a base on which
const ruc ted.
The
c r ust
is e x posed l ocal l y
of the stromatolite (see arrow on Fi gure 11 ) and
mammi l ated,
moundlike satellite struct ure.
Thi s
fine grained carbona t e cons is ts wholly of calcite and may . be
of algal o ri gin.
Regarding
origin of these stromatolites seve ral que stions
arise:
What factors are involved in deve lopment of the co l umna r
shape? Did these stromatolites originate by con vo lutio n
of an algal mat during a period of dessication? If not,
how was sediment added to upper portions of the structures?
2. What is the time frame within which such stroma t ol ites fo r m?
3.
Why is the occurrence of these stromatolites so restricted?
4.
Whi c h forms o f algae are involved in the stromatol ite - form i ng
algal mats?
5.
Under what cond iti ons and by what mechanism did the hard,
fine - grained li mestone form?
The
st r omatolit i c
st r uctu r es
at
Storr's
Lake pose some
1.
interesting
quest i ons and furnish an excellent subject for fut ure
research.
c li ff Blocks
of
Along
the coastal cliff north o f Grotto Bea ch reef b l ocks
laminated
limestone be l onging to the beach li thofacies of the
Grotto
into
Beach
Limestone
manifest various stages of incorporat i o n
the l oca l bedrock.
The beach lithofacies has been subjected
repeated l y
time s
larg e
to
the
blocks
agenc i es
of
coastal erosion, and at va riou s
have been dislodged (Figs. 12, 13).
59
Some o f
F i g . 12.
Di splaced boulders of bea chrock inco rporated int o
lmve r shoreface lithofacies
of Grotto Beach Lime - stone
on l andward s i de of largest
P l e i s tocene r eef a t the
Grotto Beach locality.
Fig. 1 3 .
Vie" along coastal cliff
d irect l y north of largest
re ef at Grot to Beach ,
show ing b l ocks of b each
lithofacies of Gro tto
Beach Lime - stone that
have been dislodged by
modern erosiona l processes.
Some of these b l ocks are
lying loosely on the c li ff
f a c e whe r eas others have
been cemented fi r ml y to
the s u bja c en t P l e i stocene
bedrock.
60
the
dislocation
occurred
Limestone
(Fig.
12),
limestone
that
are
bioturbated,
of
the
the
carbonate
planes
sand
lie
may
at
laminated
are
early
rhizomorphs
prograded
of
beach
beach
sands that
Within this progradationa l
of
limestone in which bedding
to the general strat ification, and
is
that
that
had
buried
or were
short distance north of the reef
locally
have
lie
the
similar
blocks
along
has
of
the c liff face whereas
to Pleistocene bedrock.
loose
these
by
been dislodged in recent times.
loose
firmly
p rocess
blocks,
been
active
The latter
signifying
in
that
recent
the
times.
recently cemented blocks and those of
stage of dislodgement and cementation is not everywhere
of
r ecent
coastal
blocks
of
at
a
mantled
blocks
between
sediments
However,
like
because
deposition
erosion
blocks
angles
cemented
much
Distinction
clear
extens ively
Deposition of these blocks clearly occurred in
cliff
lithification
an
oriented
across
younger
time.
these
appear
are
steep
limestone
of
others
grew
body
the reef.
coastal
Some
seawardly
in Sagamonian time.
into
Pleistocene
the
in
be chunks of beachrock that were ripped up by waves and
incorporated
burying
enclosed
Locally, this backreef lithofacies contains
that
reef
wholly
lime grainstones that are exposed landward
elongate,
g lories
buried
that
almost
fossil reef.
morning
deposition of the Grotto Beach
as manifest in large boulders of laminated
littoral
numerous,
during
the
emplacement
the
beach
e r osive
Grotto
seve ral
of some blocks clearly postda tes
lithofacies
and
cementing
but
apparent l y
processes.
preda tes
Appa rently,
Beach Limestone have been dislodged by coas tal
times
in the past, and such dislodgement is
61
continuing
is
at
the present time.
Evaporation of salt-water spray
suggested as the mechanism by which the most recently cemented
b l ocks have been bound to the bedrock exposu re.
Concluding Statement
Cementat ion
at
many
places
lithification
foregoing
1982
writer
are
rejected
wealth
on
of
on
San
Salvador
processes
text
Ma rch,
Holocene carbonate sediments is occurr ing
of
are
are
only
a
involved.
sample,
fie l d
conference.
largely
untested,
basis
of
research
Island, and a wide variety of
Sites documented in the
most being included in the
Interpretations set forth by the
and
remain
to
be
verified
or
further field and l aboratory analysis.
opportunities
awaits
the
i nterested
investigator.
References Cited
Shinn, E. A. 1969. Submarine lithification of Holocene carbonate
sediments in the Persian Gu lf: Sed i mentol ogy.
1 2: 109-144.
Stephenson, T. A., and St ephenson, A. 19 50. Life between the t i de
marks in North Amer ica, I. Florida Keys. Jour. Eco logy.
38:354-402.
Stipp, J. J. 1981. Rad iocarbon dating laboratory. University of
Miami, Miam i , Florida.
62
A