Coastal Education & Research Foundation, Inc.
Paleo-Environmental Analyses of Marsh Sequences (Clinton, Connecticut): Evidence for
Punctuated Rise in Relative Sealevel During the Latest Holocene
Author(s): E. Thomas and J.C. Varekamp
Reviewed work(s):
Source: Journal of Coastal Research, , SPECIAL ISSUE NO. 11. Quaternary Geology of Long
Island Sound and Adjacent Coastal Areas: Walter S. Newman Memorial Volume (FALL 1991), pp.
125-158
Published by: Coastal Education & Research Foundation, Inc.
Stable URL: http://www.jstor.org/stable/25735577 .
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Journal of Coastal
SI
Research
Paleo-Environmental
125-158
Analyses
Fort Lauderdale,
Florida
Fall
1991
of Marsh
for
(Clinton, Connecticut): Evidence
Sequences
Punctuated Rise in Relative Sealevel During the
Latest Holocene
E. Thomas*
and J.C. Varekamp*
department
of Earth
University
of Cambridge
of Earth and
department
Environmental
Sciences
Cambridge
CB2
Wesleyan
Sciences
3EQ, UK
University
CT 06457, U.S.A.
Middletown,
ABSTRACTI
THOMAS, E. and VAREKAMP, J.C, 1991. Paleo-environmental analyses ofmarsh sequences
(Clinton, Connecticut): evidence forpunctuated rise in relative sealevel during the latest Hol
ocene. Journal of Coastal Research, SI #11, 125-158. Fort Lauderdale (Florida). ISSN 0749
0208.
<!!!!!!!!
We developed an integrated chemical-faunal approach to paleo-environmental analysis of salt
marsh sequences. Sediment cores from the Hammock River Marsh (Clinton, Connecticut,
U.S.A.) were studied for benthic foraminiferal assemblages and sediment chemistry (Fe, Zn,
Cu, S). Foraminiferal faunal assemblages, especially the relative abundance of the species Tro
chammina macrescens, as well as the abundance of Fe, Zn and S are reliable indicators for the
flooding frequency ofmarsh sub-environments in the intertidal range. The faunal assemblages
largely reflectthe average exposure time to the atmosphere, and the sediment chemistry reflects
the trapping of fine-grained particulate matter in themarsh, and thus reflects the complemen
tary aspect, flooding frequency. Results from the chemical and faunal analyses are in close
agreement, and indicate that the Hammock River Marsh underwent three relatively sudden
periods of drowning over the last 1500 years, followed by marsh recovery.Much of the rise in
relative sea level over the last 1500 years can be accounted forby these three periods of drown
ing of themarsh. We propose that these pulses might represent true eustatic accelerations with
an estimated time span of several decades to some hundred years.
ADDITIONAL
INDEX WORDS:
ments inmarsh sediments.
INTRODUCTION
in the near
Global sea level has been rising since the ini
tiation
of the
last
about
deglaciation
15,000
years ago, predominantly because ofmelting of
the polar ice sheets and continental glaciers
(e.g., Walcott,
1972;
Clark
et al.,
1978;
Nixon,
1982). This process will continue over the fore
seeable
ning
future,
of society
in macro-
and
and
economy
and
one
micro-plan
can not neglect
the fact that shorelines will keep retreating in
the future.Models for future sea level rise are
based either on computational models that take
the rising temperature caused by the atmos
pheric anthropogenic greenhouse effect into
account,
or extrapolate
historic
trends
in rela
tive sea level rise into the next century. Many
of these
models
assume
a smooth
Climate change, marsh foraminifera, sea level rise, trace ele
time-function
for the change in sea level during the past and
91066 received and accepted in revision 28 July 1991.
future.
to this
Exceptions
general
ization are studies by Fairbridge (1961, 1981,
1987), Moerner
(1976, 1980, 1987), Rampino
and
Sanders
de
Plassche
data
as
(1982),
(1986) and Kraft et al.
others, who interpreted the
among
(1987),
available
years
van
(1981),
and Medioli
Scott
for the
indicative
last
thousands
several
of a fluctuating
pattern
of
of
sea level rise, with oscillations on the order of
hundreds
of years.
Most studies of sea level rise over the last few
millennia document age-depth profiles in sedi
ments
from
the
intertidal
range,
based
on sam
ple intervals of several hundreds of years. The
scattered
through
data
a
points
least-squares
are
commonly
connected
regression
analysis
with a straight line or with a curve based on an
exponential fitting routine (e.g., Pinter and
Gardner, 1989). These studies assume that the
scatter in data points is related to compaction,
126 Thomas and Varekamp
errors in 14Cdating (for instance, by mixing in
of older,
recycled
the
penetrating
peat
material
peat
from
or younger
roots
uncer
and
above),
tainty with regard to the position of the dated
material to sea level (see Field et al., 1979, for
a comparison
sea
of different
level
curves).
We carried out a detailed study ofmarsh sed
cores
iment
from
River
the Hammock
is more
Marshes
(Clinton, Connecticut). The sediments in these
cores (up to 2 m long) correspond to the last
1500-2000
(radiocarbon)
(van de
years
our
inter
sampling
or less. Paleo
on the order of 30 years
val was
on sediment
environmental
based
analyses,
in
and
variations
the
faunal
compo
chemistry
et al.,
Plassche
1989),
and
sition of benthic foraminifera, suggest that sea
level rise in the studied region was not a smooth
function of time but occurred in several discrete
pulses of several decades to hundreds of years
duration. Thus we suggest that the observed
scatter
an
in data
of
interval
curves
of sea-level
points
several
decades
to
with
several
hundreds of years may be (at least partially) a
true indication of fluctuations in the rate of rel
ative
sea
level
rise.
sea
If relative
level
rise
over the last 2000 years has indeed been spas
modic,
recurrence
with
of years,
hundreds
of several
intervals
the
for future
rationale
sea
level projections by linear or smooth function
a doubtful
becomes
extrapolations
undertak
area
is an
marshes
environment
and rapid variations
depositional
with mudflats
parameters.
exposed
and
to strong
environments
is characterized
by
a
specific
flora, although there are broad overlaps in the
ranges
of macrophytic
species.
The
between
low marsh.
and may
Spartina
dominate
the
other common halophytes are Distichlis
Juncus
and
spp.,
taxa
three
at
water
Salicornia
more
become
marsh, which
spring
flora;
spicata,
latter
The
spp.
common
in the
high
is the area above mean
tide.
ture of halophytic
zone
This
high
a mix
contains
and non-halophytic
floral
common
with
and
patens
species,
Spartina
as well
as Cypera
other middle-marsh
species
are
ceae.
common
where
Phragmites
species
fresh water enters the high marsh. The high
marsh is only flooded by the highest tides, and
extends up to the highest point of influence of
the tidal waters (highest high water level:
in the Clinton area about 1 m above
HHWL;
of ground water
Seepage
a low
off cause
on-average
and
MSL).
marshes,
although
run
stream
in high
salinity
the salinity may be high
as a result
during warm
periods
A gradient
in average
salinity
of evaporation.
sea
from mean
level toHHWL was documented forNova Scotia
to
are commonly subdivided into low,middle and
1972; Long and
high marsh (e.g., Redfield,
Mason, 1983; see Nixon, 1982, forConnecticut
marshes). The differences in the marsh sub
environments are best classified on the basis of
the average percentage of time that the area is
flooded, or the number of flooding events per
year. The difference in elevation between the
higher and lower of these three environments
in the Clinton area of the Connecticut coastline
is between 75 and 100 cm (tide-tables). Each
sub-environment
in the
than
diverse
is common
patens
marshes
and
(Scott
numbers
large
1978;
Medioli,
low marsh
of unicellular,
eukaryotic
erotrophic
in physical and chemical
Marsh
the area
1980).
The nutrient-rich marsh environment is host
PALEO-ENVIRONMENTAL
ANALYSES
OF MARSH
SYSTEMS
intertidal
as
characterized
estuarine
ing.
The
is generally
mean high water at neap tide and mean high
water. This zone is vegetated largely by Spar
tina alterniflora in the study area (Nixon, 1982;
van de Plassche,
this volume). The middle
marsh is the zone between mean high water and
mean high water at spring tide; the vegetation
het
benthic,
(foraminifera
organisms
and thecamoebians), which form shells (called
tests) by agglutinating small silt grains into a
matrix
of organic
material.
the mudflats
On
with
tests secreted
foraminifera
of
around
MSL
calcium
carbonate
occur
(calcite)
the agglutinated
forms;
more
numerous
become
these
in addition
calcareous
(relative
to
forms
to agglutin
ated forms as well as absolute) below MSL. The
few tests of calcareous specimens in the marsh
are
environment
usually
not
preserved
in peats
because of calcite dissolution. Agglutinated
tests (size range: 63 |xm to several hundreds of
are
fjim), however,
in large numbers.
preserved
in the
sediments
The position of foraminifera in food-chains
has not been well-documented, but they obtain
nutrients in many different ways: there are
omnivores,
some
and
Journal of Coastal Research, Special
carnivores,
herbivores,
are known
to use
taxa
Issue No. 11, 1991
detritivores,
extracellular
Rise
Punctuated
of photosynthetic symbionts {e.g.,
and
1973; Boltovskoy
Lee, 1974; Murray,
feed
Foraminifera
1976).
Wright,
largely on
metabolites
minute
as
such
organisms
diatoms,
bacteria,
and nannoplankton {e.g., LIPPS and VALEN
TINE, 1970). Several species use particulate
and dissolved organic matter, which in salt
marshes
be derived
may
macro
the dense
from
estuaries
and
marshes
organic
material in the form of fine-grained detritus,
bacteria and epiphytes is abundant, but many
of the
use
cannot
invertebrates
larger
such
the
small food items, cannot directly assimilate
or do
or dissolved
matter,
organic
particulate
occurs.
matter
the organic
not feed where
Thus
foraminifera form a key link in the estuarine
food chains, assimilating energy available from
minute
and
autotrophs,
energy
retrieving
available during the final stages of degradation
of organic debris (Lipps and Valentine,
1970;
Murray, 1973).
Marsh
microfaunal
assemblages
diversity, usually
only.
Thecamoebians
water
(e.g., Lee,
are
almost
Various
1974).
in
exclusively
in brackish
fresh water, foraminifera
low
5 to 6 species
containing
live
of
to salt
eco
and
species
phenotypes are sensitive indicators of salinity,
and the composition of the faunas at different
can be used
in cores
levels
to estimate
paleo-sal
inities (e.g.,Murray, 1968; Scott, 1976; Scott
and Medioli,
1978, 1980; Scott et al, 1987;
Allen
and
Roda,
estuaries
modern
indicate
area)
occupy
MSL,
well-defined
parallel
Leckie,
row
compared
Numerous
floral
These
to floral
zones
(e.g.,
Scott
et al., 1986; Scott
1980; Scott
1990).
on
studies
in the Nova
Scotia
(mainly
different
that
assemblages
zones
in relation
to
vertical
to marsh
and Medioli,
and
1977).
zones
faunal
zones
and
several
nar
are
zones
can be distinguished between MSL and HHWL
(Figure 1, after Scott and Medioli, 1980). For
aminifera do not occur above the upper bound
In the
ary of the high marsh (above HHWL).
topmost 5-10 cm (vertical) of the high marsh,
is essentially
the
fauna
ing
of Trochammina
zone IA in Scott
moebians
consist
monospecific,
macrescens
sub
(faunal
(fresh-water
forms)
may
co-occur
this zone. Below
macrescens
mina
and
is still
Trocham
diversity:
a common
com
faunal
ponent, with the addition of the common species
Trochammina
mata.
and
inflata
The
mon
latter
in dense
species
whereas
the
stands,
in areas
with
relatively
vegetation
common
is more
Tiphotrocha
compri
com
to be more
tends
high salinity and less dense vegetation, such as
mixed stands of Salicornia species and thin S.
IB
subzone
(faunal
patens
in Scott
oli, 1980; see below). Additional
zone
can
inner
the
ities
are
and
limnetis
and
ipohalina (Scott et al., 1981). In
of estuaries
reaches
the
where
lower Haplophragmoides
salin
manilaensis
(H. bonplandi in Scott and Medioli,
be
Medi
species in this
be Pseudothurammina
Polysaccamina
1980) may
common.
macrescens
Trochammina
decreases
strongly
in relative abundance or is absent in themiddle
and low marsh (faunal subzones IIA and IIB,
Scott and Medioli,
1980), where Miliammina
fusca
more
become
mexicana
much
and A renoparrella
common.
to MSL,
Close
calcareous
species
such as Helenina
andersoni and Protelphidium
orbiculare
with
together
forms are not
these
occur,
calcareous
but
ostracodes,
well-preserved
in the peats.
are
Foraminifera
common
very
sev
(usually
eral hundreds of specimens per cm3 of peat) in
samples deposited in the high marsh through
low marsh,
on
and
we
Therefore
can
to the
trace
intertidal
mudflats.
paleo-environmental
changes (especially changes in position relative
toMSL) through studies of changes in species
of assemblages
thecamoebians
composition
aminifera
Medioli,
in marsh
and
of agglutinated
(e.g., Scott
1978, 1980, 1986; Scott
sediment
(as
et al,
These
sequences.
in marshes
variations
for
and
1987)
faunal
to position
related
relative to HHWL) are probably largely deter
mined by the tolerance of the different species
to atmospheric
exposure.
between
A major
difference
foraminiferal
data and pollen data is that the pollen in the
peat samples may have been transported from
large
and
distances,
the floral
rep
assemblage
resents a mixture of pollen from a large region
(e.g.,
local
in
subzone IA the foraminifera
in numbers
increase
1986;
Clark,
1985).
1980). Theca
and Medioli,
127
Sealevel
former
phyte growths and the bacteria living on these
macrophytes. This abundant supply of organic
matter supports large standing crops of fora
and Walton,
minifera (Lee, 1974; Phleger
1950; Scott and Medioli, 1980).
In marine
inHolocene
Foraminifera,
environment
transport
of material
ronment,
but
Journal of Coastal Research, Special
Clark
only.
from
agglutinated
Issue No. 11, 1991
and
however,
Patterson,
represent
There
may
the
immediate
foraminiferal
be
the
some
envi
tests
Thomas and Varekamp
128
sub
zone
Upper Estuary
Central
No Forams
No Forams
1A
T. macrescens
HighMarsh
Estuary
T. macrescens
T. macrescens
T. macrescens
T. comprimata
T. comphmata
H. manilaensis
MiddleMarsh
Low Marsh
T. macrescens
T. comprimata
A
M.
T. inflata
M.
fusca
HA
T. inflata
Low Marsh
M. fusca
T. inflata
A. sa/sum
A. foliaceus
B
fusca
M. fusca
A. salsum
C. umbilicatulum
P. orbiculare
IIB
AfterMedioii and Scott, 1980
HHWL: highest highwater level
MHWS: mean highwater at spring tide
MHW: mean highwater
MHWN: mean highwater at neap tide
MSL: mean sea level
Figure 1. Marsh sub-environments with vertical distances frommean sea level (MSL) and foraminiferal assemblages
and Medioli, 1980).
are
to oxidation,
prone
and
thus
fall
apart
quickly during transport outside a small area.
Not only the foraminiferal faunas, but also
in the transect
the chemical environment
between MSL and HHWL is strongly influenced
by flooding frequency. Each flooding event car
ries
material
fine-grained
which
environmental
systems
into
the marshes,
is trapped in the marsh flora. In paleo
one may
the relative
of marsh
analyses
depositional
therefore
abundance
in
variations
apply
of clay and organic
mat
ter as a crude distinction between upper high
marsh
versus
low marsh
environments.
High
Journal of Coastal Research,
marsh
are
peats
dominated
by
organic
(after Scott
matter,
because the vigorous tidal currents that bring
in seawater with its suspended clay load do not
reach
this
ments
are
will
trap
zone
often.
frequently
clay as well
Lower
marsh
covered
as hydrous
iron-oxide
ticles that commonly precipitate
zones
mixing
et al.,
(e.g., Coonley
environ
seawater
by
and
par
in estuarine
There
1971).
forewe expect a higher clay content as well as
iron
higher
marshes
concentrations
compared
to upper
in
salt marsh
lower
salt
environ
ments.
A
Special
paleo-salinity
Issue No.
11, 1991
indicator
for
sediments
Rise
Punctuated
deposited inmarsh environments is the Sedi
mentary Phosphate Method (Nelson, 1967).
This method distinguishes fresh/brackishwater
environments
environments
saline
from
through comparison of themain cation in diage
netic phosphates: vivianite (Fe-phosphate) in
upper marshes and apatite (Ca-phosphate) in
lower
This
marshes.
method
of measuring
cation abundance of diagenetic phosphates has
in New Jersey
been applied
successfully
marshes (Meyerson, 1972), but shortcomings of
the method
(e.g.,
a result
as
of the
of
presence
detrital apatite or fish bones) were pointed out
by Guber (1969).
The salinity of the water covering the marsh
surface
affects
of marsh
diagenesis
especially
with
diagenetic
sulfides.
a
In
sediments,
to the formation
regard
of
ment the sulfur content of the sediment is rel
atively low (<1 wt. %), and the main source of
sulfur is probably decaying organic matter
(Given, 1975). Sediments
deposited under
marine conditions are enriched in sulfur up to
several
weight
percent,
and
indicator
(see
as
a
first approxi
their sulfur content may be used as a
mation
paleo-salinity
e.g.,
Raiswell
and
Berner, 1985).
The formation of diagenetic sulfides has been
the
scope
of extensive
research
(e.g.,
Berner,
1970, 1984, 1985; Lord and Church, 1983).
Three parameters may be limiting sulfur fixa
tion during diagenesis of anoxic sediments: the
of dissolved
abundance
the
in pore
sulfate
of "labile"
abundance
organic
and
the abundance of reactive iron in the sediments
(Berner, 1985). The sulfate reduction rate in
the pore fluids is largely a function of the avail
ability of labile organic matter (Berner, 1984),
which may be the limiting factor in many
marine
In
environments.
anoxic
fresh-water
sediments the supply of dissolved sulfate may
be limiting. The diffusion rate of sulfate into
the sediment column is determined by the sul
fate
concentration
gradient
from
the
surface
fluids to pore fluids at a given depth. The abun
dance of dissolved sulfate in surface waters of
water
on the mixing
depends
water
rain
(groundwater,
sea water,
the
and
and
water)
environments
estuarine
ratio
fresh
between
or river
evaporation rate, which depends among other
things on the ambient temperature. Sulfide
diagenesis
extremely
in modern
complex
marsh
and
may
environments
involve,
in addi
tion to diffusion, transport in the unsaturated
upper zones of the marsh sediment during dry
periods as well as slow movement of the pore
fluids (Casey and Lasaga,
1987). In marsh
environments
sediments
contain
commonly
more than 20 weight percent organic matter,
and the sulfate reduction rate is probably not
limited by the abundance of labile organic mat
ter. The sulfate diffusion flux into sediments
that are only sporadically flooded (upper marsh
limit the
environments)
may ultimately
amount
of sulfate
reduction
and
(Casey
Las
aga, 1987). Marsh sediments that were flooded
but became emerged may loose their sulfides
through oxidation processes (Given, 1975).
Sulfate reduction rates may be high, but
reduced
becomes
sulfur
re-oxidized
and
H2S
is
et al.,
(Howes
atmosphere
Lord
1984;
and
1983). The sulfur fixation rate is
Church,
largely determined by the contents of reactive
iron
of the
sediments.
in coastal
present
oxides
hydrous
Iron
is predominantly
as fine-grained
sediments
ferrihydrite,
{e.g.,
in the
oxides
estuarine
goethite,
as fine-grained
hematite), which precipitated
zone
mixing
(Coonley
et al., 1971). Ferric iron is reduced and the
in the pore
hydrous ferric oxides dissolve
waters, possibly mediated by bacterial activity
In saltmarsh
1989).
(Canfield,
iron
sediments
reacts with the reduced sulfur and iron sulfides
precipitate. The dominant sulfide phase in
marsh
waters,
matter,
129
Sealevel
will diffuse out of the sediment column into the
environ
low-salinity
inHolocene
is pyrite,
sediments
which
intermediary
Lord
1979;
of saline
monosulfide
and
(Howarth,
waters
In pore
the post-depositional
marshes,
pre
or through
formation
1983).
Church,
be
may
cipitated directly during diagenesis
mobil
is
ity of iron and other chalcophilic metals
of
the
solubil
limited
small
because
extremely
ity of their sulfides. In low-salinity coastal
marshes
meters
Fe-enriched
of the
it can
where
upwards,
in the upper
layer
diffuse
iron may
an
form
sediment
which
column,
centi
are
oxy
genated by the roots ofSpartina macrophytes.
In conclusion,
fur
in anoxic
environmental
of iron and
the abundances
sediments
indicators
can
only
be
used
when
as
sul
paleo
diagenetic
sulfur fixation is not primarily limited by the
availability of labile organic matter. In most
salt
marsh
environments,
the
of
abundance
reactive iron in the sediments will be the pri
mary
control
on
sulfur
fixation
in the
sedi
ments. If iron is brought into the marshes dur
Journal of Coastal Research, Special
Issue No. 11, 1991
130 Thomas and Varekamp
ing flooding as participate
in marsh
abundance
the iron
matter,
is proportional
sediments
to the number of flooding events per time unit.
The iron-rich sediments of the lower marshes
will fixmore reduced sulfur during diagenesis
than
the
low-iron,
environments.
marsh
upper
The sulfate supply or the abundance of fine
grained iron oxides in the sediments may be
sulfur fixation in the
limiting diagenetic
extreme
Trace
enter
elements
the marsh
with
ticulate flux in sea water, especially
iron
oxides
and
particulate
(Lee, 1975; Millward
this
kamp,
hydrous
matter
organic
and Moore,
We
volume).
the par
a rel
atively high Zn and Cu content in iron-rich
environments.
lower marsh
Salt
marsh
macro
phytes may partly recycle these metals through
uptake, leading to the high metal concentra
tions in Spartina spp. (Windom, 1975).
Plassche
from
(this
"lobes,"
to the north
and
south of the village ofHarbor View; Hammock
River itself is in the northernmost of the two
We
"lobes."
Fl
cores
studied
from both
core
lobes:
from the northern lobe, to the north of the
Hammock
River,
cores
several
and
(CY
cores)
from the southern lobe, just to the east ofRoute
145, the north-south road from Clinton to Kel
sey Point. Initial chemical and faunal studies
were
done
to
investigate
the
several
"black
bands" in the peat sequences using samples
from core CYX (40-135 cm depth; see Van de
Plassche, this volume). We collected additional
CY cores (CYA and CYB) about 10 m south of
the original sample location. Comparable inter
vals in lithology occur at slightly different
depths in cores from the CYX and CYA-CYB
localities (Figure 3). A complete chemical pro
file was established
for core CYB (0-155 cm
depth),
whereas
the
faunal
our
volume);
and
located
marsh,
cores
were
of several
inventory
areas
to represent
selected
of
hundreds
for lithological
typical
development of the marsh in general, without
evidence for the presence of erosional levels due
to channel
in the marsh.
migration
consisted
Sediments
amounts
of peat,with
of terrigenous
material
varying
3).
(Figure
Different levels in the cores were dominated by
different
of cord
species
patens,
Spartina
tichlis
and
grasses,
dominant
in the peat was contributed by
plant material
that
The Hammock River Marshes in Connecticut
(Bloom and Stuiver, 1963; Bloom, 1964; Van
de Plassche
et al., 1989) are located to the
southeast of the town ofClinton (Figure 2). The
of two
River
and Dis
Spartina
alterniflora,
black
horizons
were
Three
spicata.
in and
correlated
between
rec
cores
many
The
black
are
layers
between
10-20
cm thick, and occur at slightly variable depths
Sites and Lithology
consist
Indian
core
the
sediments.
marshes
from
location (cores KM),
this volume);
(Figure 3; see Van de Plassche,
the F core locality lacks the black bands in the
ANALYTICAL METHODS
Sampling
in the
in both
data
to the east of the town center of Clinton (Core
DMM; Figure 2). The lithology and floral con
tents of the cores are described by Van de
ognized
AND
SAMPLING
LOCATION,
a core
from
faunal
present
cores west of the CY
1982; Vare
therefore
expect
we
In addition,
cores
environments.
marsh
upper
occurred at exactly the same depths
cores.
contents
of the
sec
tion 0-70 cm were studied in core CYA, taken
close to core CYB. The lithology in cores CYA
and CYB is the same: "black layers" (see below)
Journal of Coastal Research,
40-60
approximate
cm,
70-100
cm,
and
100-120 cm. A detailed description of the lith
ology and stratigraphy of the cores is presented
(this volume).
by Van de Plassche
Cores (up to 2 m length) were collected with
a
steel
handcorer
with
coated
The cores were wrapped
and
field,
laboratory.
acteristics.
of clay, and macroscopic
cores were
The
centimeters
ple boundaries
boundaries.
in the
were
together with the color, estimated
of a few
slices
lacquer.
arrival
upon
split and sampled
The rhizomes
and root systems
described,
amount
acrylic
in plastic foil in the
were
sediment
cut
up
thickness,
char
in sample
sam
and
chosen at lithological
Core-sections
of constant
lithology
were cut into equal-length sections of at most 6
cm in the F and CY cores and up to 10 cm in the
KMA core. The whole core length was sampled
and
all
were
samples
tinuous
record.
Sample
Preparation
For
microfaunal
immediately
placed
analyzed,
providing
analyses
samples
in an alcohol-water
a con
were
mix
ture to prevent oxidation of the foraminiferal
tests, or kept frozen until processing (Scott and
Medioli, 1980). Samples were washed through
Special
Issue No. 11, 1991
Punctuated
Figure 2.
two
Location
sieves
(500
Rise
of the cores in the Hammock River Marshes
u.m
and
63
(xm) and
the
large
size fraction was dried and kept, but did not
contain
than
foraminifera.
63
between
and
|xm was
500
The
jim and
63
|xm was
in alcohol.
suspended
picked from the material
evaporated.
size
discarded.
For
the first
CYX, DMM, KMB)
fraction
smaller
The
fraction
dried,
weighed,
were
Specimens
cores
examined
Journal of Coastal
131
Sealevel
(CY, F and KM)
and Indian River marsh
(DM).
a split
of 0.1 gram,
and all
specimens
from that split. For the later cores
picked
so much
a small
obtained,
containing
split was
was
covered.
material
that a picking
tray
thinly
obtain
were
Specimens were picked, and if less than 100
in the tray another
present
split was made
were
at least
until
100 specimens
picked,
to obtain
obtained.
The material
used
the spec
If there were
then weighed.
less than
imens was
were
after the alcohol had
(cores
we used a microsplitter
in Holocene
to
and
Research, Special
Issue No.
11, 1991
132
Thomas
core
F1
core cya
and Varekamp
core cyx
core KMB
core kma
p
Up/a
a/p
no
data
p/a
_p/d
MpI^
p/d
p/d
50
50
data
50
~ p/d "
p
"a/p"
p/d
a/p
100
^a>^
100
-.PID-:
p/d
100
no
^a^
100
data
p
ip/d1
p/d
150
v.p/D^
O^a^
p/d
2004
Peat
iffl
E3
Black horizon
Clayeypeat
\&y--.\Sandy peat
in columns indicate rhizomes: A = Spartina
Figure 3. Lithology and rhizomes in the studied cores. Abbreviations
P = Spartina patens, D =Distichlis spicata.
25
in 5 trays
specimens
these
labeled
paper.
samples
"not
The
were
not
we
of material,
used.
stopped
and the data on
further picking of material
Such
foraminifera"
containing
was
number
of specimens
are
samples
in this
calculated
per gram of dried sediment (in the size fraction
between
imens
500
were
u.m and
picked
63
and
u.m). All
counted
mounted
spec
in cardboard
samples
for chemical
and
and
stainless
subsequently
and
pestle,
screen.
steel
a
commonly
dense
wood
small
and
root
analyses
were
Journal of Coastal
air
a glass
with
pulverized
a 180 |xm
sieved
through
coarse
was
The
fraction
amount
and
it was
pieces;
consisted
not
of
further
considered.
Splits of 2-3 grams of the sieved sediment
samples
were
leached
50 ml 8% HC1?18%
slides.
The
dried
mortar
alterniflora;
15% H202
Research, Special
was
Issue No.
added.
11, 1991
a
with
HN03
The
solution
to which
samples
were
made
of
10 ml of
stirred
Punctuated Rise
at room
procedure
temperature
dissolves
matter.
Test-runs
for 8 hours.
iron
all
This
oxides,
in Holocene
finely
pyrite
ground
showed total dissolution of the samples in 8
hours. The leachate solutions were filtered and
brought up to a volume of 100 ml. The solutions
were further diluted and analyzed for Fe, Cu,
and Zn with a flame Atomic Absorption Spec
troscope (AAS), Perkin and Elmer model 372. A
split of the leachate solution was titrated with
ION NaOH until it had reached a pH of about
6-7, brought to a fixed volume, and filtered to
remove
iron oxides.
precipitated
hydrous
were
diluted
solutions
further
and ana
the
These
in sample
dissolved
and
tralized
neu
matrices,
or
of oxalate
characteristic
in
selenate,
assume
that
an
organic
of oxa
precursor
late in the samples is oxidized during the leach
The
ing process.
from Core Fl are
"oxalate
contents"
of samples
values
rep
but these
reported,
amounts
of the oxalate
relative
resent
the
cursor
in the
carbon
Organic
pre
were
contents
not
directly
determined, but weight loss on ignition (LOI)
was determined through burning of the samples
in a furnace for 1 hour at 850?C. During this
pyrite
procedure,
to hematite,
is oxidized
lead
ing to a 33% weight loss of the pyrite fraction.
The data have not been corrected for this effect,
because the weight loss due to the release of
water
LOI
from
values
contents,
also
affects
clays
are representative
however.
A
subset
the
results.
The
of organic
carbon
was
of 5 samples
selected for analyses by Inductively Coupled
Plasma Optical Emission Spectroscopy (ICP)
for 23 elements in aqua regia leachates.
All analytical data were plotted versus depth
as follows: a sample taken between 16 and 20
cm
depth,
between
for
16.5
instance,
and
homogenized
19.5
was
cm.
as a bar
plotted
next
sample
The
value (20-25 cm depth) was plotted over the
interval 20.5 to 24.5 cm. This mode of plotting
Journal of Coastal Research,
the
were
samples
width
interval.
the
sample
minor
and
occur,
may
stretching
and
lead
processing
sampling
cm.
lution of about
2-3
subsequent
reso
to a depth
RESULTS
Faunal
Studies
The faunal assemblages (Figures 4-7; Tables
1-3) strongly resemble those described from
Nova
many
Scotia
and assemblages
of different
levels
locations,
representative
between HHWL and MSL were recognized
(Scott and Medioli,
1980; 1986; Scott et al.,
1987; Figure 1). Detailed descriptions of distri
of recent
our
the Nova
aminiferal
ponent
al.,
faunas
species
in press).
assemblages.
marsh
because
similar
but
authors
et
(Scott
in Long
by Parker
these
for
com
in their
distances
Foraminifera
(1965),
in
compared
Scotia
are very
over
large
Sound were described
Buzas
and we
is feasible
comparison
taxa
foraminiferal
not available,
with
data
Such
marsh
are
Island
(1952) and
concentrated
on the faunas in the Sound itself, and included
on marsh
few data
foraminifera.
in New
assemblages
by Parker
presented
Foraminiferal
England
and Athearn
Bay, Massachusetts;
Walton
sediment.
that
over
The field collection of the cores, during which
butions
addition to the peaks from the leachate solution
and sulfate. Independent analyses of the sedi
ments by Graphite Furnace AAS indicated that
this signal must be largely ascribed to oxalate,
and we
account
Connecticut
analyzed.
During the chromatography we observed a
peak at the end of the spectrum with a retention
time
into
(subzones)
lyzed for sulfate with ion chromatography
(Dionex, QIC model). Standards were prepared
from Na2S04
133
takes
leaching
takes met
als from clay exchange sites, dissolves sulfides
(including pyrite) and breaks down organic
with
Sealevel
(Barnstable
(Poponesset
1959) and Phleger
Marsh,
no data on
on marsh
recent
More
depth-zonations.
foraminifera
from Great
studies
Sippewisset
Marsh
also
that
Scotia
Massachusetts)
(Falmouth,
in Nova
the zones
recognized
over
wider
regions
recognized
1990).
Leckie,
suggest
can be
and
(Scott
data
Preliminary
the Hammock
from
samples
and
Massachusetts;
1950), but the authors presented
detailed
were
marshes
on
River
surface
marshes
(Table 4) are in agreement with theNova Scotia
foraminiferal distributions described by Scott
and Medioli (1980, 1986).
The lower part ofCore Fl (Figure 4; 203-149
cm)
mata
cens,
a fauna
contains
and
up
inflata, with
a depositional
suggesting
the lower middle marsh
Below
185
cm T.
by T. compri
to 25% T. macres
dominated
T.
environment
in
(higher subzone IIA).
comprimata
is more
abundant
than T. inflata, but the latter species becomes
dominant at about 180 cm. From 149-139 cm
foraminifera
Special
are
absent,
Issue No. 11, 1991
suggesting
an
environ
134
Thomas and Varekamp
Figure 4. Relative abundances
after Scott and Medioli,
1980.
ment
where
of the most common foraminiferal species
foraminifera
not
could
survive,
In the short interval
possibly above HHWL.
from 131-139 cm the fauna is dominated by T.
more
with
macrescens,
than
25%
T.
inflata
(lower subzone IB), and from 139 to 103 cm the
fauna
is strongly
dominated
by T.
macrescens
(upper subzone IB to lower IA). At 103 cm the
fauna quickly changes to become dominated by
T.
comprimata.
This
species
remains
dominant
from 103 through 80 cm, but T. macrescens
increases in relative
slowly and gradually
abundance in the upper part of this interval
(upper subzone IIA to lower subzone IB). The
section from 80 through 46 cm is again strongly
dominated by T. macrescens (subzone IA), but
at 46 cm the relative abundance of this species
decreases
through
28
The
interval
from
46
sharply.
cm contains
a mixture
of T. macres
in core F. Lithology as in Figure 3, faunal subzones
T.
cens,
in relative
24
cm;
is a short
of T.
abundance
then
the present
T.
and
comprimata
There
IB).
marsh,
its relative
marsh
(lower
inflata
interval
high
of increase
macrescens
abundance
at
decreases
28
to
surface.
For the section at CY we combined data from
cores CYA and CYX (described above, Figures
5A, 5B). The lowermost interval of core CYX
(133-140 cm) contains no foraminifera. A thin
interval
(129-133
with
macrescens,
cm)
T.
contains
comprimata,
T.
common
T.
inflata,
and
up to 25% M. fusca (subzone IIA, upper low
marsh tomiddle marsh). From 91 through 129
cm
the
fauna
is dominated
by T.
macrescens
(subzone IA to uppermost IB), with the excep
tion of the interval between 99 and 103 cm
which did not contain enough specimens for
analysis (close to or just above HHWL). From 75
Journal of Coastal Research, Special
Issue No.
11, 1991
Rise
Punctuated
TABLE
Fl
0-
Fl
Fl
Fl
Fl
Fl
Fl
Fl
6
2
6
0
46
135
0
11
2
18
6- 12
Fl
12-Fl 15
15-Fl20
20- Fl
24
24- Fl28
3
1
5
3
26
1
78
10
26
2
28-Fl32
32-Fl 36
0
0
0
0
10
6
43
14
36-Fl40
40-Fl43
43- Fl46
46Fl 50
50-Fl53
53- Fl58
3
4
1
0
18
24
94
30 0
21
8
0
0
0
0
0
1
58-Fl 62
62- Fl65
65- Fl70
70-Fl75
75-Fl80
80-Fl 85
85Fl 91
77 0
87
32
100
40
0
13
0
3
3
25
98 02
5
7
1
0
12
0
0
0
0
4
0
1
0
1
2
0
16
11
32
56
95 90
1
5
11
10
10
91Fl 96
96-103
Fl
103-107
107-111
111-115
Fl
115-118
10
2
0
10
5
0
5
6
1
2
1
118-121
Fl
121-125
Fl
0
2
2
1
125-128
Fl
128-131
Fl
131-134
Fl
134-139
Fl
139-145
145-149
149-153
Fl
153-157
Fl
157-160
Fl
Fl
160-164
164-168
Fl
168-172
Fl
172-176
Fl
176-180
Fl
180-185
Fl
185-189
5
6
0
2
0
0
0
1
0
0
4
0
0
0
0
2
2
9
2
189-194
Fl
3
194-199
Fl
199-203
1
0
0
14
7
1
4
1
0
6
14
17
7
3
15
12
4
17
84
72
25
5
11
7
13
5
3
3
5
11
0
0
18
33
11
14
11
26
29
45
37
66
^^a^^J^Jli^O
78
44
fusca,
with
T.
comprimata
too
few
foraminifera
0
0
0
0
7
0
1235
83
0
0
5
0
1855
0
303
178
74
0
0
0
0
0
0
0
0
81
0
0
0
0
0
1
1
0
0
0
0
0
0
14
2
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
3253
1620
2528
2344
1134
912
84
0
0
57
0
76
0
115
111
0
103
106
80
6
12
69
17 0
41
23 0
43 08
2811 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
1
0
1
2
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
2255
2093
1124
927
1759
1473
1
0
0
0
0
2043
1
0
0
0
1
0
0
0
0
00
0
00
0
0
00
0
0
01000
22
67 0 8
20
98150
20
81
01000
8
72250
93 0 8
1029
0
84 11
99 270
109
01000
1
1
0
86280
0
0
27600
14720
2668 0
20720
4341 0
27600
37530
42270
54150
0
0
1
1
1
0
1
2
0
4
6
0
0
61
53
5
55
and A.
mex
for analysis,
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
2
0
0
0
0
0
0
1
0
0
0
0
0
0
1151
1821
1961
2119
1118
1522
1017
195
1064
1365
1116
780
0
0
0
0
0
0
0
1
5
1
0
0
0
0
0
4
15
8
4
00
0
0
0
0
0
0
0
0
0
405
484
310
531
278
24
0
763
439
161
192
247
807
576
672
2473
0
1
0
1122
807
00
00000
0
2863
0
1
0
0
0
00
00000
0
0
0
0
0
0
0
0
0
0
300000
00000000
40
icana (subzone HA). Samples between 57 and 99
contain
0
14
34 0 6
35 0 7
55
nr/gr
110
0
to 99 cm the fauna is dominated by 7\ inflata
cm
Sealevel
1. Counts of benthic foraminifera, Core Fl.
^ Depth
Core
^^
(cm)
and M.
in Holocene
0
793
1165
with the exception of the sample from60-63 cm,
which
is dominated
by T.
macrescens
(above
highest high water to subzone IA). The fauna
between 46 and 57 cm is dominated by T.
Journal of Coastal Research, Special
Issue No.
11, 1991
136
Thomas and Varekamp
TABLE
2.
Core Depth
Counts of benthic foraminifera, CY cores.
(cm)
CYA
CYA
CYA
CYA
CYA
CYA
CYA
CYA
nr/gr
5
10
20
11
1
5
17
11
106
97
10- 13
13- 17
17- 21
21- 24
5
7
28
12
0
0
1
4
10
17
58
35
2
21
24- 27
27- 30
30- 34
34- 38
CYA
CYA
CYA
CYA
CYA
CYA
CYA
CYX
CYX
CYX
CYX
CYX
CYX
CYX
CYX
CYX
CYX
CYX
CYX
CYX
CYX
CYX
CYX
42
52
21
4
0
51
54
58
2
0
0
0
0
3
14
4
2
1
58- 62
62- 65
65- 69
69- 71
0
0
0
0
0
4
8
0
0
2
3
1
0
43- 46
46- 49
49- 53
53- 57
3
2
9
16
0
0
7
43
45
47
57- 60
60- 63
63- 67
67- 71
71- 75
75- 79
79- 83
83- 87
87- 91
91- 95
95- 99
99-103
103-109
109-115
CYX
CYX
9
2
29
50
2
0
1
384345475154-
CYA
CYA
CYA
CYA
CYA
6
0
25
64
48
48
25
4
0
45
16
29
2
0
0
0
6
6
0
0
0
60
83
0
1
0
0
5
1
0
0
0
0
33
25
48
42
0
0
0
0
0
0
25
14
5
11
0
0
0
0
717
318
1167
776
28
0
0
0
0
8
0
0
325
299
1
4
10
5
4
0
0
10
13
1
0
0
0
0
0
315
1493
294
63
5
6
1
0
0
0
0
0
0
28
79
94
77
84
10
0
1
18
17
16
3
0
3
26
36
25
59
54
59
6
23
10
10
34
129
42
2
1
23
27
36
57
85
194
127
164
2
0
1
0
0
0
0
0
2
1
0
0
0
0
2
0
2
4
0
1
41
35
29
10
2
2
1
0
0
2
0
5
96
56
83
163
1
2
4
8
2
0
0
19
0
0
2
39
49
65
68
114
91
8
63
98
104
0
0
0
0
0
0
0
0
1
2
0
0
0
0
0
79
116
18
0
0
0
0
1
25
72
29
8
7
3
0
0
0
0
0
0
3
3
0
4
0
1
2
12
5
0
0
0
0
0
0
1
0
2
0
0
2
0
7800
1007
189
334
264
35
15
19
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
8
27
19
6
1
3
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
2
0
0
0
0
0
0
0
1
0
0
890
0
0
1
0
1370
0
0
0
12
26
1290
921
628
2310
2810
2030
2900
0
25
4
1
9
2090
2400
2290
2560
1290
1050
13
720
1010
1090
CYX
115-120
CYX
CYX
120-125
125-129
CYX
CYX
43
1
20
17
15
15
0
0
0
0
0
95
2
2
133-137
0
0
0
0
2080
3
CYX
137-140
1
2
0
0
5
0
0
0
0
8
inflata,
and
129-133
macrescens,
with
T.
some M.
fusca,
T.
comprimata
(upper subzone IB). In the
uppermost sample from the core (43-46 cm) T.
inflata is dominant, after a sharp drop in rela
tive
abundance
IB).
In core CYA
of T. macrescens
(lower
subzone
62 and 75 cm is dominated by T.
common
Journal of Coastal Research,
comprimata,
and A.
inflata with
mexicana
(sub
zone IIA). The interval between 54 and 62 cm
does not contain foraminifera (above highest
high water). From 38 to 54 cm the fauna is dom
inated
(Figure 5B) the interval between
T.
by T.
macrescens
with
some
T.
compri
mata and T. inflata (upper subzone IB). There is
Special
Issue No.
11, 1991
Punctuated
TABLE
3.
Rise
inHolocene
CoreDepth (cm)
^
Stj
^
KMA
KMA
0- 11
11- 23
48
8
1
0
6
4
KMA
23- 29
29KMA
38
KMA
3848
3
1
1
1
*
2 ?
E-i
~
13
41
84
1
1
9
0
1
1
0
10
15
17
7
6330
2229
2433
21
76
0
1
4
5
1
8
3
7
18
62
20
68
4
0
2
0
84KMA
91
KMA
9196
96-100
2
0
1
0
0
1
12
31
41
5
1
0
4
2
0
12
KMB
KMB
60-KMB
64
64- 67
67- 71
KMB
KMB
71- 75
75- 78
0
0
0
1
0
0
68
44
4854
KMA
54- 58
58- 62
62- 66
66- 70
KMA
7074
74KMA
84
KMA
58
32
48
5
0
0
0
0
0
0
0
0
0
0
0
0
0
2
0
0
3
2
4
1
0
0
0
8
3
0
0
0
2
0
0
0
2
63
0
400020
400020
1
0
144
30
3
119-123
123-127
1
6
6
9
14
10
KMB
KMB
127-131
131-134
0
1
0
0
DMM4
DMM4
DMM4
150-155
155-160
4
12
1
160-164
3
33
71
3
0 6810
25
DMM4
164-172
172-180
180-185
185-190
0
0
0
0
55
24
4
0
0
0
0
0
0
0
0
0
4. Data
0
0
0
0
0
0
35 0
115-119
TABLE
0
0
108
76
46
0
0
0
KMB
KMB
KMB
DMM4
DMM4
DMM4
Hj^O
nr/gr
0
0
0
0
7 0
2314
1417
1023
4
23 84 0
73
32 49
2
2
4
3
0
1
0
0
0
0
0
0
3
0
0
0
0
0
0
0
0
0
0
0
2
0
0
0
0
0
0
0
0
0
4
0
0
5
0
0
1
0
5
0
1
0
0
9
0
0
0
3
0
3
1
0
0
70000000
50001
2
on surface samples, CY core area. Data
0
0
0
0
1
90
0
0
170
0
52
8
9
0
1
0
0
1
1
0
0
0
0
0
0
0
0
2
0
0
0
0
1
0
0
3
2
4
0
0
0
6
0
00
00
0
0
0
8
11
0
0
00000
0
54
c
-2
o
^^a^^^
41
67
0
2
0
0
KMA
KMA
KMA
137
Counts of benthic foraminifera, cores KM and DMM
2
KMA
Sealevel
254
412
220
471
1338
1617
574
1114
275
1500
1386
2250
455
3100
679
2150
1260
6
0
6
8
0
2640
0
0
1800
1170
11
14
00
1110
0
0
0
0
00000
00
0
000000
00000000
000000
00
0
0
0
0
1120
1700
1350
0
0
0
are on total (dead plus alive) foraminifera.
$3
Surface 1
Surface 2
0
8
40
123
54
0
21
2
47
101
26
0
0
2
Surface 3
87
3
46
43
8
0
29
Surface 1: S. patens (thin stands) and Salicornia
Surface 2: S. patens (dense stands)
Surface 3: S. alterniflora
Journal of Coastal Research, Special
Issue No. 11, 1991
138
Thomas and Varekamp
Figure 5. Relative abundances of the most common foraminiferal species in core CYX (Figure 5A) and core CYA (Figure 5B).
Lithology as in Figure 3, faunal subzones after Scott and Medioli, 1980. Relative abundances of the most common foraminiferal
species in core CYX (Figure 5A) and core CYA (Figure 5B). Lithology as in Figure 3, faunal subzones after Scotty and Medioli,
1980.
Journal of Coastal
Research,
Special
Issue No.
11, 1991
Rise
Punctuated
a
sudden
in relative
decrease
macrescens
at
38
and
cm,
of T.
abundance
section
the
between
21 and 38 cm is dominated by a combination of
T.
with
inflata, T. comprimata,
A. mexicana
and M.
T.
and
IIA).
One sample (17-21 cm) is again dominated by
T. macrescens (lower subzone IA to upper IB),
and then the relative abundance of this species
until
decreases
zone
marsh
the present
surface
(sub
in the
changes
core
overlapping
sec
tions of CYX and CYA were recognized in both
cores, but at slightly different depths (distance
between
these
cores
see
10 m,
about
above).
Correlations between the cores based on lith
ology, faunal fluctuations as well as sediment
chemistry (discussed further on) show excellent
A strong
of T. macrescens
in relative
decrease
agreement.
dance
occurs
just
abun
above
the top
black layer in both cores CYX (46 cm) and CYA
(38 cm); this layer is somewhat higher in core
CYA (43-54 cm) compared to core CYX (53-60
cm; Figure 3). The interval lacking foramini
fera is thicker in core CYX than in CYA (57-75
cm versus
54-62
bradyi
and
moebians in cores CY and KMA;
interval in all studied samples
two
groups
occur.
The
fauna
several
nated
by T.
with
inflata,
and A. mexicana
T.
theca
this is the only
in which these
in the
between 29 and 54 cm in core KMA
macrescens,
corre
section
The
of core KMB
topmost
across
to the section
the upper
sponds
closely
most
in core KMA.
dark horizon
The
lower sec
tion in core KMB shows a similar faunal
pattern as that across themiddle dark layer in
core CYX (Table 3): just below this dark layer
in its
upwards
of foraminifera.
additional
relates to the interval between 21 and 38 cm in
core CYA). One sample (23-29 cm) is dominated
by T. macrescens (upper subzone IB to lower
IA), and then the relative abundance of this
species decreases to the surface of the present
day marsh. The uppermost sample of the core
contains a higher relative abundance of Af.
fusca than the uppermost sample of core CYA,
which reflects the position of the latter core at
a slightly higher elevation in the recent marsh.
was
species
to pres
layers
core the most common
(Figure 7). In the DMM
H.
which
manilaenis,
was much more abundant than in the F and CY
cores.
This
inner
reaches
in the
is more
abundant
species
of estuaries
and Medioli,
(Scott
1980); core DMM is indeed much further inland
than cores CY, F and KMA (Figure 7).
of the Faunal
Studies
There are considerable fluctuations in the
faunal composition of benthic foraminifera in
all studied cores. The faunal composition was
not stable over time, and there is no simple
over the total studied
trend in assemblages
in any
interval
and
rapid
abundance
different
(i.e.,
cores.
of the
and
increase
of T. macrescens
"lobes"
relatively
Table
occur
in cores
in faunal
through E8
between
from
events
These
changes
correlation
of strong
relative
in the
of the marsh.
rapid
5). The
Intervals
decrease
sition) were labeled El
compo
(Figure 8;
faunal
events
in the cores is demonstrated in a combined plot
(i.e.,
T.
forami
in number
is a change
from absence
of fauna
across
one of these
of fauna
dark
there
ence
of the
cor
no
Black bands are also present in core DMM
from the Indian River marsh (Figure 2), and
is domi
IIA;
we
nifera;
interval
comprimata,
(subzone
part there are
see an increase
lowermost
Discussion
cm).
Faunal data on core KMA (Figure 6) are in
excellent agreement with those in cores CY and
KM, although faunal changes occur generally
at slightly greater depths in core KMA (Table
3; Figure 6). T. macrescens is dominant from 54
to 74 cm in core KMA, versus 46-57 cm in core
CYX, 38-54 cm in core CYA. A strong decrease
in relative abundance of this species occurs at
54 cm, just above the upper boundary of the top
black layer, just as in the CY cores. In the lower
part of the black layer we observed the species
Hemisphaerammina
139
Two short sections across the top and middle
black layers in the sediments were investigated
in core KMB, taken close to core KMA (Table
and
IB).
Faunal
Sealevel
3).
macrescens,
(subzone
fusca
inHolocene
relative
abundances
100 minus
macrescens)
the
for the
relative
different
of "other
abundance
cores
species"
of T.
(Figure
8).
Note that event E4 is gradual over about 10 cm
in cores F and KMA, but sudden in the CY
cores,
surface
The
the presence
suggesting
in the latter cores.
relative
abundance
of an
of T.
erosional
macrescens
reflects the vertical distance of the environment
of deposition of a sample fromHHWL (Figure 1;
Scott and Medioli,
1980): from 100% close to
in the lowmarsh. The
to
almost
absent
HHWL,
abrupt
changes
in abundance
of T. macrescens
in all studied cores indicate sudden shifts, rel
Journal of Coastal Research, Special
Issue No.
11, 1991
140
Thomas and Varekamp
Figure 6. Relative abundances of themost common foraminiferal species in core KMA. Lithology as in Figure 3, faunal subzones
1980.
after Scott and Medioli,
ative
ing),
than
the
faunal
the
or
in which
the
rise
and
marsh
in relative
rise
cannot
We
These
which
during
behind
in depositional
shallowing,
shifts
represent
periods
and
deepening
environments.
marsh
in relative
state
remained
growth
sea
level
(deepen
was
accretion
faster
sea
level
(shallowing).
that
these
unequivocally
environmental
changes
at
occurred
it is
the same time at all locations because
to
at
obtain
of
the
sediments
ages
impossible
such
the
precision.
faunal
core
from
It seems
that
however,
probable,
can be correlated
in time
changes
to core: the sequence
of events
is the
same in all cores (Table 5, Figure 8), although
the
exact
same
events
environment
for each
E3
and
core
E4,
of deposition
site.
The
interval
for instance,
is not
the
between
is characterized
by deposition high in zone IB and in IA at cores
F and KM, in zone IA (and above HHW) in cores
CY (where the situation may be complicated by
Journal of Coastal Research,
some erosion,
see above).
The
correlation
based
on faunal
events
to the cor
corresponds
closely
on lithology
relation
the cores based
between
de
(Van
this
Plassche,
and
volume),
the
cores
used in this study were selected from the large
core
studied
inventory
resent
locations
to rep
by that author
areas
of active
outside
channel
motion.
We
used
blages
tal
the
data
from
curve"
(MPE
assem
foraminiferal
a "marsh
to construct
paleo-environmen
which
curve),
the
portrays
position of the samples with respect to their
vertical distance from HHWL during deposi
tion.
sus
curve
MPE
Our
location
of all
depth
samples
in
the
between HHWL
ent
distance
curve
Special
core,
and MSL
between
8). The sections
is vertical
shows
with
the
regard
approximate
to MSL
a
assuming
these
of 1 meter (the pres
two
levels,
of the core where
represent
Issue No. 11, 1991
ver
distance
time
Figure
the MPE
intervals
where
Punctuated
Rise in Holocene
145
T. macrescens,
141
Sealevel
H. manilaensis.
%
155
165
175
3
185
CORE DMM4
195
Figure 7.
Relative
<
CO
abundances
of the most common foraminiferal species in core DMM.
marsh growth kept up with relative
rise.
Core
sections
the MPE
where
sea level
curve
swings
to the right (towards MSL) represent periods of
drowning (indicated in the figurewith D1-D3),
whereas shifts to the left represent relative
curve
was
emergence.
The
from data
of core
but MPE
curves
constructed
mainly
our most
record,
Fl,
complete
are
cores
derived
from other
at
sites
parallel:
occurred
at
all
similar
deepening-shallowing
levels
5).
(Table
At the time of deposition of the bottom layers
of core F, deposition occurred in the middle
marsh
environment.
marsh
environment
marsh
or
even
o
a.
At
faunal
changed
HHWL.
above
event
E8
the
to high
suddenly
of
This
period
Journal of Coastal
Research,
shallowing ended suddenly by drowning, with
an approximate
in elevation
change
cm. This
event
(D-l) was
drowning
the
marsh
kept
recovered,
events
(between
pace
with
(D-2)
drowning
E6
and
relative
was
and
for
E5)
marsh
sea
level
cause
the
of about
20
shortlived,
some
time
accretion
rise.
A
of faunal
new
event
E5, with a relative lowering of the depositional
site of about 30 cm with respect toHHWL. This
second
more
drowning
event
recovery
gradual
was
and a
longer-lived
of the marsh
occurred,
with a small jump at faunal
marsh
level
Special
accretion
rise
and
Issue No.
then
even
11, 1991
event E4. The
relative
up with
sea
level
outpaced
kept
sea
rise.
Thomas and Varekamp
142
MPE curve
cm above msl
IA
IB
HA
other species, %
other species, %
Other species, %
other species, %
IIB
Figure 8. Relative abundances of "other species," i.e., 100 minus the relative abundance of Trochammina macrescens, for all
(MPE) curve
studied cores. Correlation lines connect corresponding events in the different cores. The Marsh PaleoEnvironment
was constructed from the location of faunal subzones according to Scott and Medioli
(1980). Faunal events are indicated by El
through E8, drowning events by Dl through D3.
TABLE
5. Foraminiferal
faunal events and depths in core.
Depth in core, (cm)
KMA
CYX Fl
CYA
Lithology
Event
Interpretation
El flooding
E2emergence
flooding E3
E3B slight flooding
E4emergence
E5
strong
flooding
E6 gradual emergence
E7
flooding
E8 strong emergence
? 23
24
17
?282921
38
nr
55 57nr
74
62 7580
?
?
?
131
129
?
?149 ? ?
? 46
54
top black layer
?
103
91
black layer
?
133 139
black layer
nr: not recognized in the core
?
: interval not recovered in core
Event E3 represents the third drowning of the
marsh (D-3), which is suddenly terminated (E2)
and followed by a period ofmore gradual sub
mergence,
lasting
until
the present
day.
The most pronounced interval of deposition in
marsh
middle
in all
environments
cores
(rela
tively speaking, the zone with the most marine
influence) is present between about 75 and 100
cm
(after
ure
8),
D-2,
and
between
corresponds
events
E4
and
E5,
Fig
in the
to sediments
upper part of, and just above, the middle "black
layer"
in the
sediments.
The
other
two
"black
layers" (Figure 3) correspond to the other
periods of drowning (Dl and D3).
Journal of Coastal
Research,
Results
Chemical
Depth profiles of concentrations
ments
Fe,
Zn,
Cu
S as well
and
of the ele
as Loss-on-Igni
tion (LOI) values for cores F, CYB and CYX are
shown in Figures 9 and 10 (Tables 6 and 7). The
CY cores show strong Fe and S enrichments in
and
just
not
does
the
dramatic
shows
Fe,
above
contain
Zn
and
S at
peaks
similar
at 80-110
peak
in the concentrations
main
125-133
Special
"black
"black
bands."
bands"
in the
The
F
3),
(Figure
concentrations
core
but
of
a
depth
cm depth. A smaller
peak
occurs
at
of Zn and Fe
intervals,
e.g.,
cm depth in core F (Figure 9), and
Issue No.
11, 1991
Punctuated
TABLE
Core
Fl
Fl
Fl
Fl
Fl
Fl
6.
Chemical
inHolocene
Rise
data, Core Fl.
Depth
(cm)
LOI
(%)
43.8
32.9
29.0
31.6
25.7
24.9
30.9
35.5
17300
20700
23100
16600
15000
15300
14000
Fl
Fl
Fl
Fl
Fl
75 80
80 85
85- 91
91- 96
96-103
30.9
36.2
31.1
38.2
56.0
45.9
58.1
48.7
40.1
55.0
41.3
8900
11300
Fl
Fl
Fl
Fl
Fl
Fl
Fl
36
40
43
46
50
53
58
62
65
70
42.6
47.7
Fl
Fl
Fl
103-107
107-111
111-115
27.9
32.0
21.4
Fl
33.5
42.1
37.4
34.4
13200
16400
13800
13400
Fl
Fl
Fl
115-118
118-121
121-125
125-128
128-131
134-139
139-145
145-149
153-157
157-160
47.0
44.5
42.3
30.0
30.0
14500
14600
14700
20400
20300
160-164
164-168
18.3
Fl
Fl
Fl
Fl
Fl
Fl
Fl
168-172
176-180
180-185
185-189
189-194
194-199
199-203
18.3
18.9
12.0
19.2
31.8
14.8
14.8
Fl
Fl
Fl
Fl
Fl
Fl
Fl
Fl
40
43
46
50
53
58
62
65
70
75
52.5
41.2
Fe
S
(ppm)
(ppm)
0- 6
6- 12
12 15
15 20
20- 24
24- 28
28- 32
32 36
Fl
Fl
Fl
Fl
Fl
143
Sealevel
Zn
(ppm)
34.0
47.0
44.0
35.0
23.0
54.0
43.0
47.0
53.0
57.0
11.0
28.0
29.0
16.0
13000
12.0
8200
15300
20.0
23.0
11700
11300
8800
42.0
24.0
25.0
14.0
26.0
39.0
21.0
20.0
17.0
19.0
17.0
19.0
17.0
17000
16000
35400
22000
27000
15400
18000
8300
Cu
(ppm)
11.0
26.0
10.0
10.0
18.0
15.0
14.0
14.0
18100
17900
14800
21700
4000
13000
4900
6300
6100
7200
11000
31800
26300
30900
12300
17600
25900
23300
12500
14.0
14.0
14.0
18.0
20.0
23.0
40.0
32.0
34.0
42.0
13500
4800
5700
4800
5800
8700
18700
2900
5800
6600
16700
18700
18200
21300
10.0
8.0
8.0
11.0
10.0
14.0
20.0
12.0
14.0
14.0
22.0
26.0
22.0
21.0
26.0
22.0
24.0
21.0
18.0
19.0
48.0
13.0
17.0
20.0
47.0
48.0
43.0
37.0
21700
26000
29300
42300
6100
12900
12900
22.0
34.0
20.0
18.0
18.0
18.0
18.0
49.0
68.0
70.0
49.0
35.0
37.0
30.0
14400
11400
16200
25900
14900
20800
20900
12400
15000
16100
small positive Fe anomalies occur at 60 cm and
at 40-55 cm, the latter correlated with a Zn
anomaly and a small S anomaly. The clay-rich
bottom part of the F-core is relatively rich in
Fe, Zn and S. An interval with gradually
increasing amounts of S, Fe, and Zn occurs from
in an enriched
30 cm upwards, culminating
level at about 10-20 cm. The top 10 cm of the
core is less rich in Fe, whereas Zn and S con
lowest
The
remain
centrations
high.
concentrations of Fe and Zn occur between 135
and 149 cm depth and at 55 and 65 cm depth.
The positive Fe anomalies have been labeled A
F from top to bottom (Figure 9). The "oxalate"
profile for core F shows a broad positive anom
aly in the middle of the core and no significant
correlation
with
other
chemical
parameters.
Core CYB (Figure 10A) contains several pos
itive Fe anomalies, notably at 135-155, 115
125, 65-105, 45-55 and 5-15 cm depth, labeled
in the same way as the peaks in core F as peaks
A to F. The small Fe peak in core Fl (peak C)
Journal of Coastal Research, Special
Issue No. 11, 1991
144
TABLE
Thomas and Varekamp
7.
Chemical data, CY cores.
Core
(cm)_(%)
CYX 43- 46 16611
46- 49
CYX
CYX
49- 53
1015-
CYB
CYB
0
0
37.48
48.24
48.87
50.09
43.01
36.20
36.65
35.99
46.28
45.14
9643
8649
5
20.46
10 13.29
15 15.96
80.5
69.
14.6
7395
10045
5
23.
17650
49.4
6
11.
18714 24.1
40.
3
31274 14.9
61.
8
45.
7
8
14.
315.
18200
26100
22700
2800
3800
16800
14200
14400
14700
5900
3500
6000
7400
12200
13800
8800
13300
18700
13300
14300
10900
10500
11100
57.78
61.91
51.56
34.79
24.71
18.64
17.81
20.91
71.89
55.67
74.77
56.39
43.05
38.70
16.84
11.05
6.52
4.73
4.10
20.44
39.60
47.92
18400
20800
34400
23700
15000
10500
14800
21800
30300
16000
15800
17000
140-145
CYB
42.28
35.49
24.16
13000 12.89
8200
20.91
15300 24.16
25000 12.89
23700 20.98
26700 24.96
37.04
24500 25.69
41.49
23900 24.52
30.72
33500 12.22
40.43
25000 16.12
16.64
1270011.26
10.39
5200 1.25
10.48
6600 0.00
30.66
11500 0.00
26.76
20400 0.00
21.64
4500
0.00
0.11
5600 0.00
11.12
11000 7.90
17.22
16900
11800 2.09
145-150
CYB
28.90
11000
CYB
150-155
30.38
15000
9600 6.29
11300 3.94
19.86
Ditch
18500
29300
CYB
CYB
CYB
CYB
135-140
CYB
15400
21400
was not detected in the CYB core. The Fe peaks
correlate well with the Zn peaks, except for the
B peak. There is no clear correlation between
of Fe
and
Cu.
The
sulfur
pro
file shows a strong correlation with the Fe pro
file,whereas the LOI is not significantly cor
to other
4
24.
48.
6
36.0
20.98
20.76
20.81
70 18.80
75 17.12
80 18.02
85 19.90
90 25.92
95 31.49
32.38
32.47
46.78
48.88
50.11
52.80
58.26
55.76
110-115
CYB
CYB
115-120
CYB
120-125
CYB
125-130
CYB
130-135
related
18.8
9.7
8.9
24.0
3400
17.39
30 17.44
35 12.38
21.32
30.05
50 30.42
80CYB
CYB
8590CYB
CYB
95-100
CYB
100-105
CYB
105-110
the concentrations
15643
11397
0
9745
0 8456
0
677
10577
9207
20981
13524
42.66
41.29
20 16.74
20CYB25
25- CYB
30- CYB
4035- CYB
4540- CYB
CYB
455550- CYB
CYB
55- 60
6560657075-
chemical
Zn
4637
24121
CYB
CYB
05-
Cu
S
_(ppm)_(ppm)_(ppm)_(ppm)
CYX 53- 57 11009
57-CYX
60
6063
CYX
67- CYX
71
71- CYX
75
CYX
75- 79
CYX
79- 83
87
83-CYX
87- 91
CYX
CYX95
91CYX
99-103
CYX 103-109 6390
CYX 109-115
CYX 115-120
Fe
LOI
Depth
parameters.
The
less
Journal of Coastal Research,
16.48
16.74
26.35
24.72
78.04
detailed CYX data show a good agreement for
Fe, S and Zn for the D peak and possibly the E
peak. These peaks correlate well with those in
core CYB (Figures 10A, 10B).
Four
samples
were
selected
for ICP
analyses
for a spectrum of elements, two in the D peak
and two in the low Fe interval between peaks C
Special
Issue No. 11, 1991
Punctuated
Rise
S.
inHolocene
Zn.ppm
%
Sealevel
Cu.ppm
145
LOI.
%
*oxolote?
210
Figure 9. Concentrations of Fe, Zn, Cu, and S as well as LOI values versus depth for core F; "virtual oxalate"
discussed in the text; positive elemental anomalies are indicated with A-F.
contents are
160'
Figure
10A.
Core CYB. Concentrations
of Fe, Zn, Cu and S versus depth for the CY cores, together with LOI values.
and D of core F (Table 8). The Cu and Zn values
show
The
reasonable
high
agreement
are
Fe-samples
with
our AAS
characterized
by
rel
atively high levels of Zn, Se, B, V, Co, Zr, Ni
and Mo, whereas Sn, Pb, Ba, Li, Sc, Cr, Cu, As,
Sr and Y did not show significant differences
between samples with high and lower Fe-con
tents. The strongest enrichments in the high-Fe
samples
as
compared
with
the
low-Fe
Discussion
of the Sediment
Chemistry
data.
samples
were found for Zn (factor 2) and Mo (factor 2.5).
The depths of intervals with high values ofFe
and Zn in the CY cores correlate very well with
in core F.
the depths of similar anomalies
Within the resolution of our studies (3-4 cm),
we can correlate most of the peaks labeled A to
F between the two cores. The interval of overlap
between the CYX and CYB cores shows slight
differences in element profiles, but the profiles
Journal of Coastal Research, Special
Issue No. 11, 1991
Thomas and Varekamp
146
Otherspecies. %
Fe.%
u> o
w o
LOI.%
S.%
Zn, ppm
w
100
110
120
130
140
150
160
Figure
10B.
TABLE
8.
Core CYX.
data, core DMM.
Chemical
Depth
(cm)
LOI
DMM4
DMM4
150-155
155-160
DMM4
DMM4
DMM4
DMM4
160-164
164-172
172-180
180-185
185-190
30.44
34.43
37.13
Core
DMM4
TABLE
Sample
9. Results
of analyses
Li
65.75
80.64
88.31
88.87
S
Fe
(ppm)
(ppm)
11440
10804
20928
21230
13424
17065
17198
16425
21103
41217
32039
18921
7148
9567
Cr
1.4
1.5
1.3
1.5
19.8
22.6
27.0
29.8
18
20
23
24
Co
Ni
7
9
18
15
065-070
075-080
091-096
096-103
11
16
17
19
Sample
Pb
Se
S, %
Fe, %
S/Se (wt.)
065-070
070-075
5
3.0
2.8
1.8
1.5
0.63
0.72
4.2
2.6
2.59
0.60 x 104
0.54 x 104
0.62 x 104
4.5
3.1
2.33
0.69 x 104
091-096
096-103
(ppm)
81.8
45.0
24.7
31.6
10.2
53.0
22.2
9.2
5.3
4.7
20.8
48.5
15.0
of 4 samples, core Fl.
Sc
49
45
62
61
Zn
Cu
(ppm)
can be correlated straightforwardly, with peaks
at slightly different depths. Correlation
between cores according to lithology and fauna
agrees with the correlation using chemical
data.
At both core-sites we observed a trend of Cu
and Zn enrichment from about 40 cm upwards,
with superimposed anomalies (Figures 9, 10).
Journal of Coastal Research,
Zn
Cu
14.5
10.2
13.1
13.1
20.0
23.2
41.3
42.8
As
8
9
11
10
Zr
Mo
Sn
2.5
2.5
3.7
3.7
8
9
23
22
24
28
26
16
Sr
85.4
76.6
74.7
65.0
3.7
4.4
5.3
5.4
Ba
11
13
15
19
This enrichment in the topmost levels of the
cores is most likely related to anthropogenic
pollution (e.g.,McCaffrey and Thomson, 1980;
Varekamp, this volume) and should be inter
preted
mental
carefully
analyses.
with
to paleo-environ
regard
Therefore
we
consider
in the
following discussion only data for the "unpol
luted" core section, with samples from depths
Special
Issue No. 11, 1991
Punctuated Rise
inHolocene
Sealevel
147
50.0
40.0
2
30.0
Figure 12. Correlation diagrams forZn and Cu with LOI val
ues for samples fromCY and F cores with depth greater than
40 cm.
0.04-.-.-.-.-.-.-.-.-,-J
1.0
0.0
2.0
3.0
4.0
5.0
Figure 11. Correlations of Cu, Zn and S with Fe for samples
from the CYB and F cores with a depth greater than 40 cm.
genic
The
than 40 cm {i.e., pre-dating
anthropo
see Varekamp,
this volume).
influences;
a significant
shows
concentration
of Fe
=
positive correlation with that of Zn (R 0.68)
and S (R = 0.67), but a poor correlation with
that of Cu (R = 0.3; Figure 11). The Zn concen
tration
shows
a significant
negative
correlation
with LOI (R = 0.52) and a weak positive corre
lation with S (R = 0.42) (Figure 12). The concen
tration ofCu is not significantly correlated with
either S or LOI (Figure 12).
The lack of correlation between S and LOI in
the marsh peats suggests that the amount of
organic matter was not the limiting variable for
S fixation during diagenesis. The amount of
non-pyrite-bound
iron
(NP-Fe),
whereas
sulfur,
the high-Fe
con
samples
tain excess Fe with respect to pyrite. In the low
FE wt. 7.
greater
sulfur or organically
in the form of native
bound
calculated
from
molar ironminus 0.5 molar sulfur (Figure 13),
shows a strong positive correlation with total
Fe (R = 0.78). The low-Fe samples contain
excess sulfur (negative NP-Fe values), possibly
Fe
reactive
all
samples,
Fe
has
been
consumed
during diagenetic pyrite formation. In combi
nation with the positive correlation of total Fe
with S, this is strong evidence forFe-control on
formation.
pyrite
The
inorganic
chemistry
determined
largely
by the
of the peats
is
of fine-grained
input
suspended matter during flooding of the marsh.
Low marsh sections, with a higher flooding fre
will
quency,
more
trap
fine-grained
matter
(clay, silt, hydrous iron oxides) than the upper
which
marshes,
have
a
lower
flooding
fre
quency. The chemistry of the peats is probably
very sensitive to the trapping efficiency of the
marsh flora for the different grain size frac
tions, the distance from tidal gullies and max
imum depth ofwater during flooding. Measure
ment
of a parameter
indicative
for clay
contents
(e.g., Al or Rb) may provide a better estimate of
clay contents than LOI values and could serve
as
a rough
environmental
We assume
areas
trap
more
pended material
Journal of Coastal Research, Special
indicator.
that frequently flooded marsh
fine-grained,
Fe-rich
than the upper marsh
Issue No. 11, 1991
sus
realm.
148
Thomas and Varekamp
CL
CH
>
QL
I
z
o
z
Figure 13. Correlation diagram ofNon-Pyrite iron (NP-Fe) versus total Fe. NP-Fe calculated according to Fe (moles/gram)?0.5
S (moles/gram) under the assumption that pyrite is the only iron sulfide present. The Pearson correlation coefficient is 0.78; sig
nificant at >99%. Negative NP-Fe values indicate the presence of native sulfur and/or organically bound sulfur.
We do not think it probable that this change in
trace element chemistry resulted from the
shifting of the location of a marsh-channel,
at our
because
core
are
there
locations
no
indi
cations from the lithology that themarsh chan
nels shifted. In addition, the black horizons can
be recognized over a very large part of the
whole marsh, and thus are not likely the result
of the shifting of one local channel (Van de
Plassche,
the cores
this
are
of relatively
The
volume).
therefore
sudden
marsh
to middle
tion
of the Fe-rich
Fe-rich
as
interpreted
in
bands
the result
shifts from upper high
marsh
environments.
bands
occurred
Deposi
in an envi
that was more
flooded
frequently
core sections.
The
adjacent
suspended
iment fraction
in sea water
carries
adsorbed
ronment
than
the
sed
Zn,
Se, Mo and possibly Cu with it, leading to trace
metal
enrichments
in the
Fe-peak
anomalies.
The sediment layers then become enriched in S
during diagenesis, and the more Fe-rich sedi
ments fixmore S in pyrite than Fe-poor peats.
In addition, more frequent flooding provides a
it is
larger potential sulfur flux, although
unlikely that sulfur fixation is limited by the
availability of sulfate.
The chemistry ofCu in the peats is enigmatic:
there is no significant correlation between Cu
concentration
and
that
of any
other
element.
Possibly, Cu was relatively mobile during
diagenesis in polysulfide complexes, which are
common sulfur species in marsh pore fluids
(Luther et al, 1986), but we cannot assess that
for our
samples.
between
Cu
A
and
similar
other
correlation
poor
was
elements
for
found
the mudflats in the Connecticut River estuary
this
(Varekamp,
Our
chemical
volume).
data
from
surface
in
sediments
the CY location (Table 7) show high levels ofFe,
Zn and S (comparable to that of the peak levels
in the core samples) inmuds from mosquito
ditches. To some degree, the mosquito ditches
a physical
environment
represent
that
to occur
envisioned
during
a more
events:
drowning
to
similar
the
sudden
marine
pronounced
invasion during high water stands. The strong
Fe enrichments in the muds of these ditches
may
mey,
from a more
result
suspended
which
matter,
cyanobacteria-rich
of Fe-rich
ample
supply
is trapped
in the sli
bottom
muds
of the
ditches. The strong Zn enrichments are thought
to be related to the particulate Fe-influx.
Our metal data agree with data from other
marshes
and
(Windom, 1975; McCaffrey
Thomson, 1980). Iron and Zn contents of sedi
ments from the Farmington marsh (Branford,
Connecticut) are higher, but these values were
on
reported
an
"ashed
basis"
(McCaffrey
and
Thomson, 1980). Their Zn profile below 40 cm
depth
resembles
ours,
with
a
low-Zn
section
between 50 and 70 cm depth. The authors do not
present an Fe profile over the full length of the
core,
but
the "clay
abundance"
that as a first approximation
Journal of Coastal Research, Special
Issue No.
11, 1991
data
show
peaks
agree with our
Punctuated
in Holocene
Rise
at about 80-100 cm. It is
major Fe-anomaly
commonly accepted (McCaffrey and Thomson,
1980; Varekamp, this volume) that the trace
metal enrichment in the upper part of the core
from anthropogenic
resulted
Our
activity.
Sealevel
high concentrations
concentrations
Even
River
abundance
this
(Varekamp,
of Faunal
Comparison
volume).
and Chemical
Data
shows
a
composition
of faunal and chemical data
between
correlation
strong
of a sample
and
the
the
faunal
concentrations
of Fe, Zn, and S (Figure 14, 15). High relative
abundances
macrescens
of
"other
specimens)
(all
species"
occur
in samples
Fe.%
-'rooj^
p
bbbbbo
non-T.
with
occur
Zn
and
(subzone
percentage
in samples
IA,
just
below
HHWL).
of "other
abundance
of "other
species"
(e.g.,
cm depth
60
interval in core F, Figure 14). The correlation
between the Zn concentration and the relative
down
breaks
species"
in
the upper 40 cm of the cores, where there is
probably a strong anthropogenic metal input
(McCaffrey and Thomson, 1980; Varekamp,
this volume). The concentrations of Fe and Zn
are significantly correlated with the relative
of "other
species"
for samples
below
40 cm (RFe= 0.63; RZn= 0.68; Figure 16).
contents and sediment chemistry
Faunal
reflect
A comparison
of Fe and Zn. The lowest
small anomalies consisting of a single
sample show coincidence of high Fe and high
indicate that the trace-metal flux in the pre-pol
lution period was associated with iron oxide
particles trapped in the marsh during flooding.
and Thomson (1980) argued that
McCaffrey
the anthropogenic input is largely derived from
the atmosphere. In how far the suspended par
ticle derived metal flux is important in the total
metal budget of the upper 40 cm in the cores is
unclear. Supply ofmetals from settling of sus
pended hydrous iron oxides was hypothesized
for themudflat sediments from the Connecticut
estuary
of Fe
labeled "no foraminifera" (above HHWL) or
with low foraminiferal counts dominated by T.
macrescens
data
149
over
the
changes
time. The
relative
in depositional
environments
faunal
composition,
especially
of T. macrescens,
abundance
largely reflects the average time of exposure of
the marsh
surface,
and
the metal
concentra
tions are proportional to the flooding frequency
and sediment trapping efficiency of the marsh.
Other species, %
rocn^o
O
cn
Cn
Zn, ppm
O
01
b
o
b
u>
b
210
core F. "Other species" values is equal to 100
Figure 14. Comparison of Fe and Zn contents with percentage of other species in
minus the relative abundance of T. macrescens. The increase in Zn concentration from 40 cm depth upwards is an anthropogenic
pollution effect,whereas the increase of Fe and percentage of other species are related to the changing environment of deposition
as discussed in the text.
Journal of Coastal Research, Special
Issue No. 11, 1991
Thomas and Varekamp
150
%
Fe,
O
O
?*
?'
N) NJ
OWOcnO CnoO
0J."
%
Other species,
OJ (sj
cn
10
^4
cn
ocn
cn
o
Zn, ppm
N)
O
cn
-4
O . .
^_.
"T-i-a-i-j-^i
20
30
O
o
160
Figure 15. Comparison of Fe and Zn contents with percentage "other species" for cores CYX (Figure 15A) and CYB (Figure 15B).
"Other species" value is equal to 100 minus the relative abundance of T. macrescens. The increase in Zn concentration from 40
cm depth upwards is an anthropogenic pollution effect,whereas the increase of Fe and percentage of other species are related to
the changing environment of deposition as discussed in the text. Comparison of Fe and Zn contents with percentage "other species"
for cores CYX (Figure 15A) and CYB (Figure 15B). "Other species" value is equal to 100 minus the relative abundance of T.
macrescens. The increase in Zn concentration from 40 cm depth upwards is an anthropogenic pollution effect,whereas the increase
of Fe and percentage of other species are related to the changing environment of deposition as discussed in the text.
The Fe abundance in the sediments is likely a
primary feature of the peats, whereas the S
abundance is a diagenetic feature, partly influ
enced by the Fe abundance.
between
faunal
and
that this chemical
Journal of Coastal Research, Special
Issue No. 11, 1991
Fe
The agreement
abundances
signature
confirms
(Fe-abundance)
Punctuated
Rise
in Holocene
Sealevel
151
The cause of the drowning of the marsh can
as yet not be ascertained: itmight have been an
100
in the
increase
rate
of true
rise
sea-level
(eus
tatic rise), a tectonic lowering of the land area
(during seismic events), or a change in the tidal
in the marsh,
range
which
would
our
change
reference level ofHHWL. The latter might be
caused by morphological changes in the marsh
and river mouth, or be related to a regional
change in tidal range, but these factors are dif
to evaluate.
ficult
A tectonic lowering of the land may cause a
local
in sea
rise
apparent
level.
Nelson
co
and
workers applied the marsh foraminiferal tech
nique to distinguish between the different salt
marsh
100
75
50
25
?-?0^
Figure 16. Correlation of percentage of other species with Fe
and Zn contents in core F; samples from greater than 40 cm
depth. "Other species" value is equal to 100 minus the relative
abundance of T. macrescens. Both correlations are significant
(>99%) with Pearson correlation coefficients of 0.68 (Zn) and
0.63 (Fe).
reflects the conditions of deposition of the sed
iments at the time when the faunas were living,
than
diagenesis.
These two different data sets lead us to a sim
ilar
reconstruction
paleo-environmental
of the
marshes through time. Both lines of evidence
indicate the occurrence of three periods during
which
the marsh
faster
than
drowned:
accretion
marsh
sea
level
rise
8).
(Figure
was
These
periods of drowning of the marsh are reflected
in the lithology of some cores (CY, KM, but not
F) by "black bands," which can be traced
throughout a large part of the Hammock River
marsh
(Van
de
Plassche,
this
volume).
The
black color is most likely caused by the pres
ence of finely divided Fe-sulfides. The vertical
extent of the Fe-rich bands indicates that for
some time the rate of relative sea level rise
exceeded
the marsh
accretion
rate.
After
some
time, marsh accretion caught up with relative
sea level rise and from then on the accretion
rate equaled the rate of relative sea level rise,
or
in some
instances
exceeded
the
rate
of rela
tive sea level rise, which led to emergence (Fig
ure
8).
Journal of Coastal Research,
the west
along
(e.g., Nelson
earthquakes
OTHER SPECIES. %
rather
sub-environments
coast
of the U.S.A. (Oregon) and found evidence for
sea level jumps. They
sudden apparent
as indicative of major
those
data
explained
and
1988).
Jennings,
We do not think that seismic events are a prob
able cause for all the flooding events of the
Hammock
River
are
events
Marshes
to be
expected
tectonic
because
whereas
sudden,
the
drowning started gradually during the young
est and middle event. In addition, the start of
the youngest drowning pulse must have
occurred approximately in the late part of the
last
no major
earthquakes
in Connecticut
and
century,
to have
known
occurred
are
during
that period.
If the periods of drowning can be recognized
over
a
seaboard,
area
the northeastern
U.S.
along
larger
are
over
a
that
and
coeval
area,
change in the rate of true sea level rise is the
more
probable
A
explanation.
comparison
of our
data with studies from the New Jersey coast
(Meyerson, 1972) and Barnstable marsh (MA,
fideMeyerson, 1972) suggests that in all three
areas
surges
were
in submergence
observed
rates. McCaffrey
and Thomson (1980) indi
cated a period of rapid relative sea level rise
from about 1900 till recent, preceded by more
gradual
relative
sea
level
rise.
Patton
and
Horne
(this volume) found a steepening in
their sea level curve around (or postdating)
1670 AD. Tide gauge data fromNew York har
bor also indicate an elevated rate of relative sea
level rise over the last 80 years compared to
average
sea
level
rise
over
the
last
1500
years
et at., 1989). Comparable
(Van de Plassche
results were obtained from England by Allen
and Rae (1987; 1988). The increased metal con
Special
Issue No.
11, 1991
152 Thomas and Varekamp
tents in the top of our sediment cores probably
an
represent
we
can
metal
anthropogenic
the
of metal
level
date
1850 (? 40 years) AD
approximately
this
kamp,
The
volume).
and
input,
increase
of sea
rates
increased
at
(Vare
level rise reported by the work cited above all
started around that period. Thus we suggest
that fluctuations in the rate of true sea level
rise
(eustatic
a
are
acceleration)
likely
expla
nation for the last drowning period and possibly
for all three periods of drowning in the Clinton
marshes.
CONCLUSIONS
Marsh
ment
foraminiferal
reliable
sedi
and
provide
of dep
on the environment
information
osition ofmarsh peats through time. Building
largely on the work of Scott and Medioli
(1980) for faunal information, we have devel
oped a combined chemical-faunal method of
reconstruction
paleo-environmental
salt marsh
sequences.
as well
as
the
The
relative
of coastal
chemical
signatures
of foramini
abundance
relative
and
of the
abundances
relative
high
species
of
abundances
T.
T. inflata, and espe
comprimata,
occur
in sam
A.
mexicana
and
fusca
the
species
ofM.
cially
ples with high concentrations of Fe, Zn, and S,
and probably indicate a depositional zone in the
middle
marsh
of T.
abundances
with
environment.
low
are likely deposited
struction
faunal
relative
High
occur
macrescens
concentrations
of Fe,
Zn
and
close to HHWL.
in samples
S, which
The con
Marsh
sea
level
rise
sediment
over
time.
is
chemistry
largely
mined by the relative strength of sediment and
vegetational input terms. The fixation of sulfur
is largely limited by the
during diagenesis
abundance of Fe and not by the availability of
organic
or
matter
sulfate.
The
Zn
contents
of
marsh
sediments that predate anthropogenic
pollution correlate strongly with Fe abun
dances, and are therefore thought to relate to
the
same
process:
trapping
of fine,
Fe-rich
sus
pended matter with adsorbed Zn in the marsh
during flooding. Thus construction of profiles of
foraminiferal
faunal
assemblages
and
concen
as
well
and
investigations
towards
paleo-seismic
of marsh-configura
studies
tion.
Data
from the Hammock River Marshes
(Clinton, Connecticut) provide evidence that
marsh accretion during the last 1500-2000
did
occur
not
three
characteristic
natures.
The
from
progressing
chemical
and
was
drown
faunal
the most
to sudden
whereas
the middle
and
drowning,
more
were
events
somewhat
gradual.
these
three
youngest
During
accretion
marsh
periods,
sig
sudden,
emergence
partial
We
evenly.
of marsh
periods
event
oldest
and
smoothly
major
recognize
ing with
fell mark
edly behind the rate of relative sea level rise.
The explanation of this change in relative rates
rise
level
and marsh
can
accretion
not
yet
be fully ascertained, but the periods of drown
ing of the marshes may be related to periods
an
with
marsh
rate
increased
events
These
also
may
chusetts;
the
ognizable
of the sea
at several
years
locations
rise
level
(about
level
rise.
in
recognized
worldwide.
40%)
occurred
have
may
Obviously,
sea
level
relative
over
during
there
whereas
pulses,
sea level
in mean
periods.
average
been
and Massa
Jersey
seems
event
to be rec
youngest
short
relatively
a small
increase
vening
sea
of true
have
from New
sequences
Much
the
last
the
three
was
only
inter
in the
extrapolation
over
the
rise
of
last
1500 years tomake predictions for sea level in
the next
deter
as
studies
1500
curves
of paleo-environments
from
us to reconstruct
in
data
enabled
jumps
relative
rise
of sea
feral species are largely related to flooding fre
Low
quency.
T. macrescens
allow the identification of periods during which
the marsh accretion kept up with, exceeded, or
fell behind relative sea level rise. This tech
nique may be applied towards detailed sea level
years
assemblages
marshes
coastal
from
chemistry
trations
of the elements
S versus
Fe, Zn and
will
enable
the reconstuction
of
depth-in-core
the paleo-environments
and will
of the marsh,
could
century
be
severely
in error.
Our
MPE graph (Figure 8) indicates that we have
entered a period of a gradual increase in the
rate of relative sea level rise during this cen
tury. The occurrence of several periods in the
last 1500 years with increased rates of apparent
sea
level
rise may
suggest
that
atively rapid rate of relative
related
necessarily
to an
the current,
rel
sea level is not
anthropogenic
green
house effect. The relevance of the drowning
pulses and correlation with global climatic
changes
Plassche
Journal of Coastal Research, Special
are
discussed
et al,
Issue No.
in press).
11, 1991
elsewhere
(Van
de
Punctuated
Rise
ACKNOWLEDGMENTS
We
thank
David
for a
Scott
construc
tive review. Students from the Department of
Earth and Environmental Sciences ofWesleyan
were
University
in the
instrumental
labor
intensive tasks of data collection: we thank
John Kimbrough, Jeffrey Levine, Wei-Yang
Fang and Jeanine Greinen for their efforts in
the chemical studies, the students of class
E&ES 251-253 (fall 1989) for their time and
effort in faunal studies (core KMA) and Ulandt
Kim forhis faunal investigations of core F. ICP
of some
analyses
at XRAL
peat
laboratories,
samples
were
Toronto,
carried
Canada.
out
Partial
financial support for this study was provided by
the Nature
ter),
Conservancy
(Connecticut
Chap
Protec
of Environmental
the Department
tion of Connecticut,
the Connecticut River
Watershed Council, and by a grant from the
Shell Foundation to the E&ES Department to
promote
undergraduate
research.
Partial
fund
ing was provided by a grant from the Connect
icut SeaGrant College Program through NOAA
grant number NA 90 AA-D-SG443, project nr.
R/OE-2. This is a contribution to IGCP Project
274, and University of Cambridge contribution
ES 1892.
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studies.
Foundation
forForaminiferal Research, Special
Publication, 17, 35, pi. 4, Figures 8-11.
The species is absent to rare in samples from
the highest marsh, is absent in samples from
the
inner
area
estuarine
(Core
com
and
DMM),
prises up to 25% of the fauna in subzone IIA
(subzone
name
after
and Medioli,
Scott
SYSTEMATIC TAXONOMY
All specimens studied were picked and placed
in cardboard slides. Taxonomy follows Scott
and Medioli
(1980), except where emended in
Medioli
and
Scott
(1986), and where indicated.
Haplophragmoides manilaenis Andersen 1953,
Two new species ofHaplophragmoides from the
Coast.
louisiana
and
(Cushman
Broenni
for For
Foundation
Cushman
aminiferal Research Contributions, 4, 22, pi. 4,
8a,
Figures
b.
hancocki
Haplophragmoides
salsum
1980).
Andersen
manilaensis
Haplophragmoides
Ammotium
mexi
Forami
littoral
and
Parker
McCulloch,
and
Cushman
Athearn
Ecol
1959,
nimann, 1948, Some new species and genera of
Foraminifera from brackish water of Trinidad:
ogy ofMarsh Foraminifera in Poponosset Bay,
Journal ofPaleontology,
Massachusetts:
33,
339, pi. 50, Figures 2, 3.
Todd and
bonplandi
Haplophragmoides
Cushman
Broennimann,
mann).
Laboratory
Research
and
Cushman
salsus
Ammobaculites
for
Contributions,
24,16,
Broen
Foraminiferal
7
pi. 3, Figures
titative
butions
9.
salsum
Ammotium
mann), Parker
Marsh
Foraminifera
and
(Cushman
and Athearn,
Broenni
1959, Ecology of
in Poponosset
Bay,
Mas
sachusetts: Journal ofPaleontology, 33, 340, pi.
50, Figures 6, 13.
Ammotium
salsum
(Cushman
and
Broenni
mann). Scott and Medioli, 1980, Quantitative
studies ofmarsh foraminiferal distributions in
Nova Scotia: implications for sea level studies.
Cushman
Foundation
for Foraminiferal
Research, Special Publication, 17, 35, pi. 1, Fig
ures
11-13.
This species occurs as a few single specimens
in few samples only.
level
Scott
and Medioli,
of marsh
studies
in Nova
Scotia:
Cushman
studies.
1980,
implications
Foundation
for sea
for Fora
miniferal Research, Special Publication,
pi.
in our
samples
as that figured in Scott
eral
siders
17, 35,
8-11.
4, Figures
The
species
Scott,
Quan
distri
foraminiferal
however,
studied
is clearly
and Medioli
type material
and
of Haplophragmoides
species
H.
bonplandi
Todd
and
the same
(1980).
of sev
now
con
Broennimann
1957 to be conspecific with H. manilaensis
Andersen 1953 (written comm., 1988). The spe
cies is usually present at less than 10% of the
assemblage, with the exception of the samples
from the inner reaches of the marshes
(core
DMM) where it reaches up to 50%.
Journal of Coastal Research, Special
Issue No. 11, 1991
156 Thomas and Varekamp
Helenina
anderseni
tValvulineria
(Warren)
and
Walton,
1950, Ecology ofmarsh and bay foraminifera,
Barnstable,
ence,
American
Mass.,
248,
Pseudoeponides
Foraminifera
dation
of Sci
Louisiana:
1957,
andersoni
for sea
implications
Contribu
level
studies of marsh
in Nova Scotia:
studies.
forForaminiferal Research, Special
Publication, 17, 40, pi. 5, Figures 10, 11.
calcareous
in almost
is absent
species
lower.
Hemisphaerammina
Tappan
bradyi
Loeblich
and
Hemisphaerammina
bradyi
Loeblich
and
in: Loeblich,
1957
Beckmann,
J.P.,
and
E.M.,
H.,
in Forami
Studies
Museum
National
Tappan,
Gallitlelli,
H.M.,
J.C.,
Troelsen,
U.S.
nifera;
A.R.,
Bolli,
Bulletin
215,
Loeblich
and
224, pi. 72, Figure 2.
Hemisphaerammina
and
Scott
Tappan,
tive
studies
in Nova
tions
studies.
bradyi
Scotia:
Cushman
1980,
Medioli,
of marsh
Quantita
foraminiferal
distribu
for sea
implications
feral Research, Special Publication,
1, Figures
4, 5.
This
species
occurs
mon,
as
rare,
however,
is absent
single
in a
in most
specimens;
few
level
for Foramini
Foundation
17, 40, pi.
or
samples,
it is more
com
in the
lower
samples
part of, and just below, themiddle "black layer"
in the sediment in the CY and KM cores.
Miliammina
fusca (Brady)
fusca Brady,
Quinqueloculina
Brady,
G.S.,
and
Robertson,
D.,
The
1870,
in:
ostracoda
and foraminifera of tidal rivers. With analysis
and
description
of Foraminifera
by H.B.
b.
Journal
of
pi. 50, Figures
11,
12.
Miliammina
1980,
studies
Quantitative
cations
sea
for
Foundation
level
17, 40,
pi.
of marsh
fora
Scotia:
impli
in Nova
studies.
Cushman
Research,
for Foraminiferal
Publication,
and Medi
fusca (Brady) Scott
Special
2, Figures
1-3.
(10-40%)
in
The species is absent in samples from higher
marsh
from
common
areas,
samples
IIA.
subzone
all
samples with the exception of a few samples
(subzone IIA) in core KMA, and in surface sam
ples from the Spartina
alterniflora zone or
Tappan,
Journal
19a,
Massachusetts:
Bay,
33, 340-341,
Paleontology,
Cushman
Foundation
This
1, Figures
pi.
and
fusca (Brady) Parker
1959, Ecology ofMarsh Foraminifera
Athearn,
oli,
and
American
Mass.,
280,
miniferal distributions
Scott
(Warren)
Medioli,
1980, Quantitative
foraminiferal distributions
248,
Miliammina
Foun
12-15.
tions, 8(1), p. 39, pi. 4, Figures
Helenina
Bayou
Cushman
Research
for Foraminiferal
of Science,
in Poponosset
Warren,
of the Buras-ScoeFIELD
southeast
region,
Journal
b.
2, Figures
22a,
anderseni
pi.
Barnstable,
minifera,
Phleger
sp.,
Brady,
part II: Annual Magazine
ofNatural History,
series 4, 6, 47, pi. 11, Figures 2, 3.
Miliammina
and
fusca (Brady), Phleger
of
marsh
and
fora
Walton,
1950, Ecology
bay
Journal of Coastal Research,
Polysaccamina
ipohalina
Scott
Polysaccamina
ipohalina
Scott,
ish-water
nia
and
n.
gen.,
foraminifera
description
n.
sp.,
Research,
ures 4a-c.
6, 318,
from
Polysaccamina
Publication,
The
imens
for sea
on
level
and
studies of marsh
in Nova Scotia:
studies.
Cushman
Research,
for Foraminiferal
17, 43, pi. 2, Figures 8-11.
Protelphidium
Arctic
Scott
Scott,
ipohalina
is commonly
species
or fragments.
Nonionina
Califor
of Polysaccamina
ipohalina,
Journal
of Foraminiferal
text Fig
1-4,
pi. 2, Figures
Medioli,
1980, Quantitative
foraminiferal distributions
implications
Foundation
Brack
1976,
southern
as
present
Special
rare
spec
On
some
orbiculare (Brady)
orbiculare
Brady,
from
Foraminifera
the Austro-Hungarian
1881,
soundings
North
Polar
obtained
Expedi
tion of 1872-76: Annual Magazine
ofNatural
History, 8, 415, pi. 21, Figure 5.
Protelphidium orbiculare (Brady) Scott and
Medioli,
1980, Quantitative studies of marsh
in Nova Scotia:
foraminiferal distributions
for sea
implications
level
studies.
Cushman
Foundation forForaminiferal Research, Special
Publication, 17, 43, pi. 5, Figure 7.
Haynesia
and
ine
orbiculare
(Brady)
Scott,
Schafer,
Eastern
Canadian
estuar
1980,
a framework
foraminifera:
for comparison.
Medioli,
Journal ofForaminiferal Research,
10, 205-234
(in footnote).
This
calcareous
species
is absent
in almost
all
samples with the exception of a few samples
(subzone IIA) in core KMA, and in surface sam
Special
Issue No. 11, 1991
the
from
pies
lower.
Punctuated
Rise
zone
or
alterniflora
Spartina
Pseudothurammina
inHolocene
and
(Scott
Medioli
limnetis
1980, Quantitative studies ofmarsh foramini
feral distributions inNova Scotia: implications
for sea level studies. Cushman Foundation for
Research,
Foraminiferal
17, 43, pi. 1, Figures
1-3.
limnetis
Pseudothurammina
Medioli),
Publication,
Special
and
and
Duffett,
1981, Marsh Foraminifera fromPrince Edward
Island: their recent distribution and applica
tion
sea
for former
level
Maritime
studies.
iments and Atlantic Geology, 17, 126.
is rare, usually
species
or fragments.
specimens
The
single
sed
present
More
common
and
(Cushman
comprimata
Broennimann)
Trochammina
arenaceous
waters
Foraminifera
of Trinidad:
from
the
shallow
Tiphotrocha
Contributions,
Parker
Broennimann),
24,
and
Journal
Massachusetts:
1959,
Athearn,
in Poponosset
of Paleontology,
33, 341, pi. 50, Figures 14-17.
(Cushman
comprimata
Tiphotrocha
Scott
Broennimann)
studies
butions
level
in Nova
studies.
and Medioli,
Scotia:
Cushman
1980,
implications
and
Quan
distri
foraminiferal
of marsh
for sea
17, 44,
1-3.
5, Figures
A common species in many samples (up to
65%), with the exception of those from the high
est marsh
is more
S. patens,
in areas
areas.
common
less
In surface
the
species
samples
zones
in densely
of
vegetated
common
in less dense
and
stands
of common
Salicornia
growth.
Trochammina inflata (Montagu)
Nautilus
1808, Testacea
inflatus Montagu,
Brittanica,
supplement,
Exeter,
Woolmer, pi. 18, Figure 3.
England,
American
Mass.,
1959,
of Marsh
Ecology
in Poponosset
nifera
Parker
(Montagu),
inflata
Athearn,
Forami
Jour
Massachusetts:
Bay,
nal ofPaleontology, 33, 341, pi. 50, Figures 18
20.
inflata (Montagu) Scott and
1980, Quantitative studies of marsh
Medioli,
for sea
implications
Foundation
studies.
Scotia:
Cushman
1-3.
macrescens
Trochammina
Trochammina
Brady,
1870,
Trochammina
Brady
(Montagu)
inflata
p. 290, pi.
macrescens
var. macres
5a-c.
11, Figures
Phleger
Brady,
1950, Ecology ofmarsh and bay
and Walton,
foraminifera,
Barnstable,
American
Mass.,
Journal ofScience, 248, 281, pi. 2, Figures 6-9.
macrescens
Trochammina
and
1959,
Athearn,
Ecology
in Poponosset
Brady,
Parker
of Marsh
Forami
Jour
Massachusetts:
Bay,
nal ofPaleontology, 33, 341, pi. 50, Figures 23
25.
Jadammina
Brand, Parker
Marsh
Bartenstein
polystoma
and Athearn,
in Poponosset
Foraminifera
and
1959, Ecology of
Mas
Bay,
sachusetts: Journal ofPaleontology, 33, 381, pi.
50, Figures 21, 22, 27.
Trochammina
Research,
for Foraminiferal
Publication,
Present
in Nova
studies.
level
17, 44-45,
in most
pi.
3, Figures
dominant
samples,
ples from the highest marsh
T. polystoma
variant
Trochammina
Rotalina
was
ochracea
ochracea
not
and
Scott
studies
Quantitative
distributions
for sea
implications
Foundation
Brady,
inflata
1980,
Medioli,
of marsh
Scotia:
Cushman
Special
1-8.
in sam
(subzone IA). The
observed.
(Williamson)
Williamson,
1858,
On
Recent Foraminifera of Great Britain, Royal
Society (London) Publication, 55, pi. 4, Figure
113.
S.
Journal of Coastal Research,
level
forForaminiferal Research, Special
17, 44, pi. 3, Figures 12-14, pi. 4,
Publication,
cens
in Nova
distributions
foraminiferal
foraminiferal
for Fora
Foundation
miniferal Research, Special Publication,
pi.
41,
and
(Cushman
Foraminifera
Ecology ofMarsh
titative
for
Laboratory
comprimata
and
nifera
1-3.
8, Figures
Bay,
and
new species of
Cushman
Research
Foraminiferal
pi.
Cushman
comprimata
1948, Additional
Broennimann,
Barnstable,
rare
(up to a few percent) in samples from the lower
part of, and just below, the "black layer" in
cores CY and KM.
Tiphotrocha
foraminifera,
Journal of Science, 248, 280, pi. 2, Figures 1-3.
Figures
as
Phleger
(Montagu),
inflata
1950, Ecology ofmarsh and bay
Trochammina
(Scott
Williamson
Scott,
Trochammina
Trochammina
and Medioli,
Scott
157
and Walton,
limnetis
Thurammina(?)
Sealevel
Special
Issue No. 11, 1991
158 Thomas and Varekamp
Trochammina
ochracea
(Williamson),
Scott
and Medioli,
studies of
1980, Quantitative
marsh foraminiferal distributions inNova Sco
tia: implications for sea level studies. Cushman
Foundation forForaminiferal Research, Special
Publication, 17, 45, pi. 4, Figures 4, 5.
Occurs
as
a few
only.
Journal of Coastal Research, Special
Issue No.
11, 1991
specimens
in a few
samples