U.S. Department of the Interior

U.S. Geological Survey

Chronology from Sediment Cores Collected in 

Southwestern Everglades National Park, Florida

Open-File Report 2012–1275
Chronology from Sediment Cores Collected in 

Southwestern Everglades National Park, Florida

By C.E. Bernhardt, G.L. Wingard, D.A. Willard, M.E. Marot, 

B. Landacre, and C.W. Holmes

Open-File Report 2012‒1275

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

SALLY JEWELL, Secretary

U.S. Geological Survey

Suzette M. Kimball, Acting Director 

U.S. Geological Survey, Reston, Virginia: 2013 

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Suggested citation:

Bernhardt, C.E., Wingard, G.L., Willard, D.A., Marot, M.E., Landacre, B., and Holmes, 

C.W., 2013, Chronology from sediment cores collected in southwestern Everglades 

National Park, Florida: U.S. Geological Survey Open-File Report 2012‒1275, 59 p.

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imply endorsement by the U.S. Government.

Although this report is in the public domain, permission must be secured from the 

individual copyright owners to reproduce any copyrighted material contained within 

this report.
iii

Contents

Abstract ......................................................................................................................................................... 1

Introduction.................................................................................................................................................... 1

Acknowledgments ......................................................................................................................................... 1

Methods......................................................................................................................................................... 4

210Pb Analyses........................................................................................................................................... 4

137Cs Analyses........................................................................................................................................... 4

Pollen Biostratigraphic Analyses................................................................................................................ 4

14C Analyses .............................................................................................................................................. 5

Age Models................................................................................................................................................ 5

Age Model Results and Discussion ............................................................................................................... 8

Big Lostmans Bay (GLW504–LMA) ........................................................................................................... 8

Second Bay Lostmans River (GLW705–SBLM2A) .................................................................................... 9

First Bay Lostmans River (GLW705–FBLM1A)........................................................................................ 10

Broad River Bay (GLW504–BRA)............................................................................................................ 11

Tarpon Bay (GLW504–TBA).................................................................................................................... 12

Harney River 2A (GLW705–HR2A).......................................................................................................... 13

Harney River 1A (GLW705–SHR1A) ....................................................................................................... 14

Shark River 2A (GLW705–SR2A)............................................................................................................ 15

Shark River 1A (GLW705–SR1A)............................................................................................................ 16

Roberts River (GLW504–RRA)................................................................................................................ 17

Summary and Future Study......................................................................................................................... 18

References Cited......................................................................................................................................... 19

Appendix A. Lead-210 (210Pb) Data from Cores .......................................................................................... 21

Appendix B. Pollen Diagrams ...................................................................................................................... 35

Appendix C. Calibrated Age Ranges (Intcal09) ........................................................................................... 41

Appendix D. Age Model by Core ................................................................................................................. 44

Figures

1. Core location map. The satellite image of the southwest part of the Florida Everglades displays 

the general location of cores discussed in this report ....................................................................... 2

2. Total 210Pb activity in decays per minute per gram on the x-axis...................................................... 7

3. Age model for Big Lostmans Bay core.............................................................................................. 8

4. Age model for Second Bay Lostmans River core ............................................................................. 9

5. Age model for First Bay Lostmans River core ................................................................................ 10

6. Age information for Broad River Bay core ...................................................................................... 11

7. Age model for Tarpon Bay core...................................................................................................... 12

8. Age information for Harney River 2A core ...................................................................................... 13

9. Age information for Harney River 1A core ...................................................................................... 14

10. Age model for Shark River 2A core ................................................................................................ 15

11. Age model for Shark River 1A core ................................................................................................ 16

12. Age information for Roberts River core........................................................................................... 17
iv

Tables

1. Core information and analyses conducted.......................................................................................... 3

2. Results of radiocarbon (14C) analyses on core samples..................................................................... 6
v 

Conversion Factors

Inch/Pound to SI

Multiply By To obtain

Length

inch (in.) 2.54 centimeter (cm)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

SI to Inch/Pound

Multiply By To obtain

Length

centimeter (cm) 0.3937 inch (in.)

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi)
1 

Chronology from Sediment Cores Collected in 

Southwestern Everglades National Park, Florida

By C.E. Bernhardt, G.L. Wingard, D.A. Willard, M.E. Marot, B. Landacre, and C.W. Holmes

Abstract

Age model data are presented for 10 cores from the southwestern coastal mangrove zone 

of Everglades National Park, Florida, collected in Common Era (CE) 2004 and 2005 and used 

for paleoecological analysis. Carbon-14 (14C), lead-210 (210Pb), cesium-137 (137Cs), radium-226 

(

226Ra), and pollen biostratigraphic information is included, and age models were generated for 6 

of the 10 cores. Age reversals and sediment disturbance prevented construction of age models on 

the remaining four cores. Four cores present a continuous record of the last 50 to 100 years, 

making them useful for analyzing the impacts caused by changes in water management in south 

Florida. These cores are Harney River 2A and Harney River 1A, Shark River 2A, and Roberts 

River. 

Introduction

Accurate age models from sediment cores are necessary for determining the timing of 

changes in sedimentation rates and proxy assemblages, as well as correlating these changes to 

known anthropogenic land-use practices and regional and global climate change. This report 

focuses on age models for 10 cores collected along riverbanks and in bays of the southwest 

coastal area of Everglades National Park, Florida (fig. 1; table 1). 

Understanding the timing of changes in proxy assemblages (such as mollusks, pollen, and 

ostracodes) in critical environments within the Everglades aids in the interpretation of key 

factors forcing environmental change, be it land use or climate. This information is important for 

management decisions dealing with the restoration of the natural hydrology of the Everglades as 

mandated by the Comprehensive Everglades Restoration Plan (CERP) (U.S. Army Corps of 

Engineers, 1999). 

Acknowledgments

We thank the staff of Everglades National Park for their cooperation in this study; the 

work described here was conducted under National Park Service Study #EVER–00141. This 

project was funded by the U.S. Geological Survey (USGS) Greater Everglades Priority 

Ecosystems Science (GEPES) effort under the coordination of G. Ronnie Best. 

A number of people assisted in the collection and processing of the cores. We especially 

thank James B. Murray, Rob Stamm, Thomas Sheehan, Carlos Budet, and Ruth Ortiz (USGS). 

Reviews by Thomas Cronin and Miriam Jones (USGS) improved the manuscript. Bethany 

Stackhouse (USGS) assisted in the final preparation of this report. 
2 

Figure 1. Core location map. The satellite image of the southwest part of the Florida Everglades displays 

the general location of cores (red circles) discussed in this report. From north to south, and east to west 

along transects: LM = Big Lostmans Bay (GLW504–LMA); SBLM = Second Bay Lostmans River 

(GLW705–SBLM2A); FBLM = First Bay Lostmans River (GLW705–FBLM1A); BR = Broad River Bay 

(GLW504–BRA); TB = Tarpon Bay (GLW504–TBA); HR2 = Harney River 2A (GLW705–HR2A); SHR = 

Harney River 1A (GLW705–SHR1A); SR2 = Shark River 2A (GLW705-SR2A); SR1 = Shark River 1A 

(GLW705–SR1A); RR = Roberts River (GLW504–RRA). See table 1 for information on cores. 
3 

Table 1. Core information and analyses conducted. 

[Cores listed in order by river system, from north to south, and from east to west (downriver) along the transects. (See figure 1 for location.) Abbreviation: cm, centimeters]

Map 

Symbol 

(fig. 1) Core ID Core name Latitude Longitude

Core 

length in 

barrel (cm)

14C*** 

(number of 

samples)

Other 

analyses

Use for 

paleoecologic 

analyses

LM GLW504–LMA Big Lostmans Bay 25 34.02 81 05.86 61.5 2 Potentially for 

older portion of 

record

SBLM GLW705–SBLM2A Second Bay Lostmans River 25 33.877 81 09.171 114 √ 3 Cs Yes, for older 

portion of record

FBLM GLW705–FBLM1A First Bay Lostmans River 25 32.819 81 12.362 119 √ 4 Ra No

BR GLW504–BRA Broad River Bay 25 30.14 81 02.31 129 4 No

TB GLW504–TBA (–TBB) Tarpon Bay 25 25.23 80 59.95 108 √ (B) √ (B) 6 Yes, for older 

portion of record

HR2 GLW705–HR2A Harney River 2A 25 25.411 81 03.802 106 √ √ 3 Cs Yes, for last 50 

years

SHR GLW705–SHR1A Harney River 1A (South Harney, near 

mouth)

25 24.580 81 08.491 170 √ √ 4 Cs Yes, for last 50 

years

SR2 GLW705–SR2A Shark River 2A (channels) 25 22.649 81 03.849 145 √ √ 5 Cs Yes, whole core

SR1 GLW705–SR1A Shark River 1A (near mouth) 25 22.462 81 06.588 115 √ √ 6 Cs No

RR GLW504–RRA (–RRB) Roberts River (near mouth) 25 16.21 80 55.69 98.5 √ (B) √ (B) 2 Yes, for 20th 

century portion

Analyses conducted

210Pb* Pollen**

*Lead-210 data are in appendix A. Figure 2 illustrates total 210Pb activity. (B) indicates data from a B core. All other analyses from A cores.

**Pollen biostratigraphic plots are shown in appendix B. (B) indicates data from a B core. All other analyses from A cores.

***Carbon-14 data are shown in Table 2.
4 

Methods

Twenty piston cores were collected from ten sites in Everglades National Park on May 4 

and 5, 2004 and July 12–14, 2006 (table 1; fig. 1). Duplicate cores, A and B, were taken side by 

side at each site (10–20 centimeters (cm) apart for most cores, ~1 meter (m) apart for GLW705–

SBLMA & B). X-radiographs of the A cores were made, and the upper 10 to 20 cm of each A 

core were cut into 1-cm segments for analyses; for sections below 10 to 20 cm core depth the 

samples were cut into 2-cm segments. The subset A cores were set aside for faunal analyses 

(ostracodes, foraminifera and mollusks) and where possible for pollen, lead-210 (210Pb), and 

sediment and shell geochemistry. Because several cores collected in 2004 were used completely 

for mollusk and gastropod analysis, in some cases the B cores were utilized for pollen, 210Pb, and 

sediment geochemistry. Portions of the subset B cores will be archived for any additional 

analyses that may be necessary. Complete core descriptions can be found in Wingard and others 

(2005, 2006). 

Chronology of the cores was developed using carbon-14 (14C), 210Pb, and pollen 

biostratigraphy (see table 1 for list of analyses conducted on each core) as described below. In 

addition, for some cores radium-226 (226Ra) or cesium-137 (137Cs) were analyzed by gamma 

spectroscopy (Robbins and Edgington, 1975). 

210Pb Analyses

Lead-210 radiometric dating is used to calculate sediment accumulation rates for the last 

100 years of deposition. The accumulation rates were calculated by applying the constant initial 

concentration [CIC] model to the excess 210Pb activity (Appleby and Oldfield, 1992). Lead-210 

data can be found in appendix A, and total 210Pb activity is shown in figure 2. 

137Cs Analyses

Cesium-137 is an anthropogenically produced radioisotope that was introduced into the 

atmosphere as a result of nuclear weapons testing. Cesium-137 is removed from the atmosphere 

by wet and dry precipitation. It is particle reactive and readily attaches to particulate matters 

whereby it is incorporated into to the sediment record. Based on atmospheric fallout, the first 

occurrence of 137Cs in the sediment record is in the early CE 1950s, with a significant peak 

occurring at CE 1963–64. 

Pollen Biostratigraphic Analyses

In this report, the first occurrence of pollen of Casuarina equisetifolia, an exotic species 

introduced to south Florida about CE 1900 (Langeland, 1990), is used to confirm 210Pb and age 

model results. Pollen of C. equisetifolia first occurs in south Florida sediments at CE 1910±15 

years and is common only in sediments deposited after CE 1940 (Wingard and others, 2003). 

Increases of woody and shrubby pollen, for example Morella, in south Florida can generally be 

attributed to the drier conditions approximately 400 years ago (Willard and others, 2006) and can 

be used to cross-check age model results. Pollen diagrams with biostratigraphic data are in 

appendix B. 
5 

14C Analyses

Radiocarbon dates (14C) were obtained on wood, plant fragments, peat, and shells by Beta 

Analytic, Miami, Fla. Shells were used only in a few circumstances and are noted on the age 

models below. See Wingard and others (2007, p. 16, 38–39) for a discussion of the problems 

associated with using shells for 14C in south Florida. Dates in table 2 are presented as calibrated 

years before present (CE 1950) (cal. yr. BP). Plants that were respiring carbon after the start of 

thermonuclear bomb testing (CE 1950) will have an excess of 14C. As a result, these samples 

cannot be assigned an age and are labeled as “pMC” or postmodern carbon. These samples are 

not reported as calibrated ages (table 2).

Age Models

Age models were constructed using the computer program Clam (methodology described 

in Blaauw, 2010) and available 14C, 210Pb, 137Cs, 226Ra, and pollen biostratigraphic information. 

Radiocarbon dates were calibrated using the Intcal09 calibration curve (appendix C). Age 

models are based on linear interpolation between dates. Age models were not run on cores that 

had many age reversals (for example when an older date is above a younger date with limited 

overall dates collected, and on cores where the radiocarbon dates are nearly identical regardless 

of depth). 
6 

Table 2. Results of radiocarbon (14C) analyses on core samples.

[Analyses conducted by Beta Analytical, Miami, Fla. Abbreviations: cm, centimeters; yr. BP, years before present (CE 1950); pMC, 

postmodern carbon]

Core Depth in cm

Beta Analytical 

sample ID

Material 

dated

Measured 

radiocarbon (yr. BP) +/-

Conventional 

radiocarbon (yr. BP) +/- 13C/12C ratio

GLW504–LMA 20–22 206418 peat 1230 40 1230 40 -25.3

GLW504–LMA 46–48 206419 peat 2430 40 2420 40 -25.8

GLW705–SBLM2A 28–30 286361 wood 1220 40 1170 40 -28

GLW705–SBLM2A 76–78 286362 wood 2370 40 2320 40 -28.3

GLW705–SBLM2A 108–110 286363 wood 3890 40 3880 40 -25.4

GLW705–FBLM1A 34–36 286364 wood 170 40 150 40 -26

GLW705–FBLM1A 52–54 286364 wood 120 40 60 40 -28.6

GLW705–FBLM1A 82–84 286364 wood 120 40 90 40 -27

GLW705–FBLM1A 108–110 286364 wood 320 40 310 40 -25.4

GLW504–BRA 24–26 206415 wood 220 40 180 40 -27.7

GLW504–BRA 50–52 206416 wood 2240 40 2210 40 -27.1

GLW504–BRA 68–70 206417 wood 112.5 +/- 0.4 pMC na 112.8 +/- 0.4 pMC na -26.5

GLW504–BRA 110–112 206414 wood 70 40 60 40 -25.9

GLW504–TBA 12–14 206421 wood 290 40 260 40 -27

GLW504–TBA 26–28 232722 wood 640 40 590 40 -28.2

GLW504–TBA 34–36 232723 wood 1380 40 1310 40 -29.4

GLW504–TBA 42–44 206422 wood 1500 40 1450 40 -27.9

GLW504–TBA 50–52 206423 wood 1320 40 1260 40 -28.6

GLW504–TBA 80–82 232724 peat 3510 40 3500 40 -25.7

GLW705–HR2A 32–34 286354 wood 102.9 +/- 0.4 pMC na 103.0 +/- 0.4 pMC na -25.9

GLW705–HR2A 48–50 286355 wood 270 40 220 40 -28.2

GLW705–HR2A 96–98 286356 wood 150 40 120 40 -26.9

GLW705–SHR1–A 34–36 286357 wood 310 40 280 40 -27.1

GLW705–SHR1–A 84–86 286358 wood 290 40 200 40 -30.2

GLW705–SHR1–A 120–122 286359 wood 270 40 220 40 -28.2

GLW705–SHR1–A 160–162 286360 wood 350 40 270 40 -29.8

GLW705–SR2A 15–16 232717 wood 170 40 150 40 -26.2

GLW705–SR2A 36–38 232718 shell 610 40 860 40 -9.7

GLW705–SR2A 66–68 232719 wood 700 40 680 40 -26.2

GLW705–SR2A 86–88 232720 wood 1230 40 1200 40 -27.1

GLW705–SR2A 102–104 232721 wood 3720 40 3730 40 -24.5

GLW705–SR1A 20–22 232711 shell 124.4 +/- 0.5pMC na 120.3 +/-0.5pMC na -8.7

GLW705–SR1A 44–46 232712 shell 440 40 710 40 -8.5

GLW705–SR1A 44–46 232713 wood 210 40 180 40 -26.7

GLW705–SR1A 62–64 232714 shell 510 40 790 40 -8.2

GLW705–SR1A 100–102 232715 shell 530 40 810 40 -7.9

GLW705–SR1A 100–102 232716 wood 170 40 150 40 -26.5

GLW504–RRA 56–58 286353 wood 3010 40 3020 40 -24.5

GLW504–RRA 82–84 206420 plant material 1970 40 1950 40 -26
7 

Figure 2. Total 210Pb activity in decays per minute per gram (dpm/g) on the x-axis. Depth in the core in 

centimeters on the y-axis. See appendix A for data. Note: For GLW705-SR2A below 39 cm, samples were 

analyzed every 10 cm.
8 

Age Model Results and Discussion

Big Lostmans Bay (GLW504–LMA)

The chronology for this core is based on two 14C dates and assignment of the top sample 

to CE 2004 (year the core was collected) (fig. 3, table 2). No pollen or 210Pb analyses were 

conducted on this core; therefore we cannot accurately constrain the 20th century. The age model 

for this core indicates it would be adequate for studies focused on the late Holocene at centennial 

scale resolution; however, additional analyses would be useful. 

Figure 3. Age model for Big Lostmans Bay core (GLW504–LMA). Blue control points on the age model 

diagram represent the measured range of possible radiocarbon ages (table 2). Age-depth values are listed 

in appendix D. In lithologic column, P represents peat. Cal. yr. BP., calibrated years before present (CE 

2004).
9 

Second Bay Lostmans River (GLW705–SBLM2A)

The chronology for this core is based on three 14C dates and 210Pb (fig. 4, table 2). Lead210 is at background levels at 12 cm (fig. 2) and the calculated sedimentation rate places CE

1950 at approximately 9 cm. Cesium-137 was detectable in one sample at 6–7 cm, but could 

indicate a high flow event rather than the CE 1964 peak. The age model suggests that there are 

several changes in sedimentation rates, including one at approximately 1,000 cal. yr. BP. Due to 

the compressed and partly disturbed post-CE 1900 upper section, this core cannot be used for 

20th century reconstructions. The consistent age model for the lower portion of the core indicates 

this could be used for mid- to late Holocene centennial scale analyses. 

 

Figure 4. Age model for Second Bay Lostmans River core (GLW705–SBLM2A). Blue control points on 

the age model diagram represent the measured range of possible radiocarbon ages (table 2), and green 

are 210Pb control points. Age-depth values are listed in appendix D. In lithologic column, P represents peat. 

Cal. yr. BP., calibrated years before present (CE 2004).
10

First Bay Lostmans River (GLW705–FBLM1A)

The age model for this core is based on four 14C dates and 210Pb (fig. 5, table 2). Lead210 is at background at 2 cm (fig. 2), confirmed by 226Ra. Therefore, the 20th century is not 

represented in the core sediments. There are large errors in the model primarily due to the 

amount of variability in this part (around CE 1700) of the radiocarbon calibration curve (see 

range of possible ages in figure 5). With the lack of sediment detailing the 20th century and the 

large 14C errors, this core is not useful for paleoenvironmental analysis. 

 

Figure 5. Age model for First Bay Lostmans River core (GLW705–FBLM1A). Blue control points on the 

age model diagram represent the measured range of possible radiocarbon ages (table 2), and green are 

210Pb control points. Age-depth values are listed in appendix D. Cal. yr. BP., calibrated years before 

present (CE 2004).
11

Broad River Bay (GLW504–BRA)

Radiocarbon samples from this core all date to near modern (fig. 6, table 2). Only one 

date at 51 cm is older (~2,000 cal. yr. BP); this sample lies just below the unconformity between 

the unconsolidated sediment and the peat. There is no 210Pb or pollen to constrain the last 

century, and therefore no reliable age model could be constructed. 

Figure 6. Age information for Broad River Bay core (GLW504–BRA). Blue control points on the age 

model diagram represent the measured range of possible radiocarbon ages, and the yellow rectangle is a 

postmodern carbon sample (table 2). In lithologic column, P represents peat. Cal. yr. BP., calibrated years 

before present (CE 2004).
12

Tarpon Bay (GLW504–TBA)

The Tarpon Bay core chronology is based on six 14C dates and 210Pb (fig. 7, table 2). The

210Pb age model indicates that CE 1950 is between 11 and 13 cm; however, 210Pb does not follow 

a typical decay profile in this core. It fluctuates a great deal and does not reach background 

levels. The first occurrence of Casuarina in the replicate core from this site (GLW504–TBB) is 

at 20–22 cm. The presence of pollen from the Brazilian Pepper (Schinus), which was introduced 

during the 20th century, in the upper 15 cm also indicates that these sediments were deposited 

during the 20th century. There are two noticeable changes in sedimentation rate before and at 

1,000 cal. yr. BP. The pollen profiles from the replicate core (appendix B) show clear patterns 

that most likely record local changes in sea level (Willard and Bernhardt, 2011). Overall, this 

core is reliable for paleoenvironmental analysis of the mid- to late Holocene at a centennial scale. 

Figure 7. Age model for Tarpon Bay core (GLW504–TBA). Blue control points on the age model diagram 

represent the measured range of possible radiocarbon ages (table 2), green are 210Pb and biostratigraphic 

control points, and red are points removed from the age model. Age-depth values are listed in appendix D.

In lithologic column, P represents peat. Cal. yr. BP., calibrated years before present (CE 2004).
13

Harney River 2A (GLW705–HR2A)

Radiocarbon dates from the Harney River 2A core have age ranges including modern 

ages at all depths (fig. 8, table 2); therefore, no age model was run. Excess 210Pb is present in the 

upper 38 cm of the core (fig. 2). Although 210Pb measurements did not reach background levels, 

a sedimentation rate of 1cm/yr was calculated for this upper portion of the core. 137Cs levels drop

between 40 and 50 cm, which suggests that sediment deposited at 40 cm is less than 50 years old. 

The first occurrence of Casuarina is at 45 cm. This core appears to provide the opportunity for 

high-resolution analysis of the last 50 years of deposition. 

Figure 8. Age information for Harney River 2A core (GLW705–HR2A). Blue control points on the age 

model diagram represent the measured range of possible radiocarbon ages, the yellow rectangle is a 

postmodern carbon sample (table 2), and green represents 210Pb and biostratigraphic control points. Cal. 

yr. BP., calibrated years before present (CE 2004).
14

Harney River 1A (GLW705–SHR1A)

Four radiocarbon dates from the South Harney River Mouth core also have age ranges 

including modern time at all depths (fig. 9, table 2); therefore, no age model was run. Based on 

210Pb, the upper 5 cm appear slightly disturbed (fig. 2), so a calendar year was not calculated 

from the sedimentation rate because we do not know how much time is represented by the upper 

few centimeters. At 15 cm 210Pb reaches background, but excess 210Pb activity is again present 

between 20 and 30 cm. The core segment between 15 and 19 cm may have been deposited under 

different conditions. Cesium-137 was measured at 20 cm, indicating that the material above that 

depth was deposited within the last 50 years. The first occurrence of Casuarina further 

constrains the 20th century to the upper 25 cm of this core. Based on 210Pb, 137Cs and pollen, the 

upper 25 cm of this core is usable for paleoenvironmental analysis of the last 50 years of the 20th

century.

Figure 9. Age information for Harney River 1A core (GLW705–SHR1A). Blue control points on the age 

model diagram represent the measured range of possible radiocarbon ages (table 2), and green represent

210Pb and biostratigraphic control points. Cal. yr. BP., calibrated years before present (CE 2004).
15

Shark River 2A (GLW705–SR2A)

The chronology of this core is based on pollen biostratigraphy, 210Pb and four 14C dates 

(fig. 10, table 2); a radiocarbon sample from a shell at 37 cm was treated as an outlier and 

excluded from the model. According to the 210Pb profile the upper 8 cm are disturbed (fig. 2), so 

calculation of a calendar year based on the sedimentation rate is not possible because the amount 

of time represented by the upper few centimeters is unknown. The first occurrence of 137Cs is at 

18–19 cm and constrains the sediment above to being deposited post-1954. Background 210Pb is 

reached at 20 cm, which is generally consistent with the first occurrence of Casuarina at 21 cm 

depth. Schinus pollen in the upper 21 cm further confirms that this sediment is post-20th century 

in age. The timing of rise in Morella pollen, ~250 cal. yr. BP, appears consistent with general 

trends in the region (Willard and others, 2006). There is a change in sedimentation rate at 

approximately 1,000 cal. yr. BP, near a subtle shift in the sediment type at 96 cm from peaty to 

sandy organic mud. The entirety of this core, from 4,000 cal. yr. BP to modern, appears 

chronologically robust for paleoenvironmental analysis. 

Figure 10. Age model for Shark River 2A core (GLW705–SR2A). Blue control points on the age model 

diagram represent the measured range of possible radiocarbon ages (table 2), green are 210Pb and 

biostratigraphic control points, and red are points removed from the age model. Age-depth values are listed 

in appendix D. Cal. yr. BP., calibrated years before present (CE 2004). 
16

Shark River 1A (GLW705–SR1A)

We attempted to construct an age model based on pollen biostratigraphy, 210Pb and six14C 

dates (fig. 11, table 2). Lead-210 dating places CE 1950 between 20 and 24 cm (fig. 2). Cesium137 was measured in select depth intervals between 0 and 20 cm. Cesium-137 was still present at 

low activity levels at 20 cm, also suggesting that the upper portion of the core was deposited in 

the latter half of the 20th century. The first occurrence of Casuarina is at 61 cm depth. This

biostratigraphic marker for the beginning of the 20th century is below a radiocarbon-dated shell 

that returned an age of 750 to 670 cal. yr. BP. The presence of Schinus pollen in the upper 60 cm 

further supports that this sediment is post-20th century in age. There are no other discernible 

patterns in the downcore pollen assemblages to constrain the age. The base of the core, 101 cm, 

was dated twice. One date is essentially modern while the second is 789 to 674 cal. yr. BP. This 

core is an example of the problem noted previously in south Florida that shells typically date 

older than wood (Wingard and others, 2007), and this discrepancy prevents us from developing a 

confident age model for this core. 

Figure 11. Age model for Shark River 1A core (GLW705–SR1A). Blue control points on the age model 

diagram represent the measured range of possible radiocarbon ages, the yellow rectangle is a postmodern 

carbon sample (table 2), green are 210Pb and biostratigraphic control points, and red are points removed 

from the age model. Age-depth values are listed in appendix D. Cal. yr. BP., calibrated years before 

present (CE 2004).
17

Roberts River (GLW504–RRA)

The two 14C dates are reversed (fig. 12, table 2). However, the 210Pb profile appears 

robust (fig. 2) and based on the sedimentation rate of 0.39 cm/yr, CE 1950 is at ~21 cm. The first 

occurrence of Casuarina is at 25 cm. The increase in Quercus, Amaranthaceae, and Asteraceae 

pollen and fern spores, with a decrease in Nymphaea pollen, indicates a change, perhaps drying, 

at this site during the 20th century. While more dating is needed to resolve the age reversals and 

construct an age model, this core has a reliable chronology for paleoenvironmental analysis 

documenting the last century. 

 

Figure 12. Age information for Roberts River core (GLW504–RRA). Blue control points on the age model 

diagram represent the measured range of possible radiocarbon ages (table 2); green represents 210Pb and 

biostratigraphic control points. Cal. yr. BP., calibrated years before present (CE 2004).
18

Summary and Future Study

The current status and additional steps required to potentially refine the record of 

deposition in the southwestern coastal area of Everglades National Park are as follows:

Big Lostmans Bay. This core requires pollen biostratigraphic data and 210Pb dating to constrain 

the last 100 years of deposition. The age model indicates the core could potentially be used for 

late Holocene studies, but would benefit from additional radiocarbon dates. 

Second Bay Lostmans River. Although the 20th century portion of this core appears reliable, the 

compressed record makes it difficult to use for analyses of the flora and fauna. The older portion 

of the core can be used for paleoenvironmental analyses; however, additional radiocarbon dates 

would further refine the age model. Also, collection of a replicate core would be useful to 

confirm if the problems with dating the last 100 years of deposition are unique to this core or 

characteristic of this site.

First Bay Lostmans River. No portion of this core can be used for paleoenvironmental 

analyses. Collecting a replicate core could be useful to capture the last 100 years of deposition or 

characterization of the site. Also, collecting a core deeper than 100 cm and dating those deeper 

sediments would help refine late Holocene sedimentation history in this area. 

Broad River Bay. Currently, no portion of this core is useful for paleoenvironmental analyses. 

Pollen biostratigraphy and 210Pb dating should be done for this core to confirm if entirety of the 

core was deposited within the last 100 years (based on the radiocarbon dates). 

Tarpon Bay. The lower portion of this core can be used for analyses of the mid- to late 

Holocene. The 210Pb record could be refined by collecting a replicate core. Additional 

radiocarbon dates between 40 and 60 cm would further refine the age model. 

Harney River 2A. Currently, the upper 45 cm can be used for analyses of the last 50 years. A 

replicate core could confirm if the 210Pb and 137Cs data are correct and also confirm if the 

sediment at this site is significantly disturbed, as the modern dates at depth indicate. 

Harney River 1A. Currently, the upper 25 cm can be used for analyses of the last 50 years. 

Lead-210 dating from a replicate core could confirm if this core is useful for paleoenvironmental 

analysis of the 20th century.

Shark River 2A. Overall, the age model appears robust. Additional radiocarbon dates between 

40 and 100 cm, using wood instead of shell for consistency, would help refine the age model.

Shark River 1A. Components of this age model seem consistent (210Pb profile, postmodern 

carbon, 137Cs); however, because the radiocarbon ages of the wood samples all date to near 

modern and the pollen biostratigraphic marker falls below a radiocarbon age of 750 to 670 cal. 

yr. BP, we cannot confidently use the core for paleoenvironmental analysis. This core provides 

an interesting contrast between shell and wood radiocarbon dates. 

Roberts River. The 20th century 210Pb profile appears robust and the upper portion of the core 

can be used for paleoenvironmental analysis of the 20th century. Additional radiocarbon dates are 

needed to clear up the age reversal in the lower portion of the core. 

While returning to the same sites and obtaining replicate cores may help us answer 

specific questions about these ten cores, we should also pursue a strategy of locating additional 
19

core sites. Locating undisturbed sediment within the channels of the Shark River Slough and 

southwestern coastal area of Everglades National Park is proving to be more difficult than 

similar efforts in Florida Bay and Biscayne Bay. The directional flow dynamics of water in the 

region may be a factor, as well as the paucity of sub-aquatic vegetation to anchor the sediments. 

It is also likely that hurricanes or coastal storms in the locations closer to Florida Bay and the 

Gulf of Mexico constantly rework the sediments, which may cause age reversals (Kang and 

Trefy, 2003); and the upriver locations are more protected from the impacts of severe storms and 

the consequent reworking of sediments. 

Additional investigations and regional comparisons may shed light on the sedimentary 

and paleoenvironmental history of the southwestern coastal area of Everglades National Park. 

References Cited

Appleby, P.G., and Oldfield, F., 1992, Application of lead-210 to sedimentation studies, in

Ivanovich, M., and Harmon, R.S., eds., Uranium-series disequilibrium: applications to earth, 

marine and environmental sciences: Oxford, Oxford University Press, p. 731–778. 

Blaauw, Maarten, 2010, Methods and code for ‘classical’ age-modeling of radiocarbon 

sequences: Quaternary Geochronology, v. 5, iss. 5, p. 512–518. 

Kang, W.-J., and Trefry, J.H., 2003, Retrospective analysis of the impacts of major hurricanes on 

sediments in the lower Everglades and Florida Bay: Environmental Geology, v. 44, no. 7, p. 

771–780. 

Langeland, K.A., 1990, Exotic woody plant control: Florida Cooperative Extension Service 

Circular 868, 16 p. 

Robbins, J.A., and Edgington, D.N., 1975, Determination of recent sedimentation rates in Lake 

Michigan using Pb-210 and Cs-137: Geochimica et Cosmochimica Acta, v. 39, no. 3, 

p. 285–304. 

U.S. Army Corps of Engineers, 1999, Central and southern Florida comprehensive review study; 

final integrated feasibility report and programmatic environmental impact statement: 

Jacksonville, Fla., U.S. Army Corps of Engineers, 4,034 p. [Available at 

http://www.evergladesplan.org/] 

Willard, D.A., Bernhardt, C.E., Holmes, C.W., Landacre, B., and Marot, M., 2006, Response of 

Everglades tree islands to environmental change: Ecological Monographs, v. 76, no. 4, 

p. 565–583. 

Willard, D.A., and Bernhardt, C.E., 2011, Impacts of past climate and sea level change on 

Everglades wetlands: placing a century of anthropogenic change into a late-Holocene context: 

Climatic Change, v. 107, no. 1–2, p. 59–80. 

Wingard, G.L., Cronin, T.M., Dwyer, G.S., Ishman, S.E., Willard, D.A., Holmes, C.W., 

Bernhardt, C.E., Williams, C.P., Marot, M.E., Murray, J.B., Stamm, R.G., Murray, J.H., and 

Budet, C., 2003, Ecosystem history of southern and central Biscayne Bay: Summary report on 

sediment core analyses: U.S. Geological Survey, Open-File Report 03–375, 110 p. [Available 

at http://sofia.usgs.gov/publications/ofr/03-375/] 

Wingard, G.L., Cronin, T.M., Holmes, C.W., Willard, D.A., Budet, C.A., and Ortiz, R.E., 2005, 

Descriptions and preliminary report on sediment cores from the southwest coastal area, 

Everglades National Park, Florida: U.S. Geological Survey Open-File Report 2005–1360, 

28 p. [Available at http://sofia.usgs.gov/publications/ofr/2005-1360/]
20

Wingard, G.L., Budet, C.A., Ortiz, R.E., Hudley, Joel, and Murray, J.B., 2006, Descriptions and 

preliminary report on sediment cores from the southwest coastal area, Part II: Collected July 

2005, Everglades National Park, Florida: U.S. Geological Survey Open-File Report 2006–1271, 

33 p. [Available at http://sofia.usgs.gov/publications/ofr/2006-1271/] 

Wingard, G.L., Hudley, J.W., Holmes, C.W., Willard, D.A., and Marot, M., 2007, Synthesis of age 

data and chronology for Florida Bay and Biscayne Bay cores collected for Ecosystem History of 

South Florida’s Estuaries Projects: U.S. Geological Survey Open-File Report 2007–1203, 127 p. 

[Available at http://sofia.usgs.gov/publications/ofr/2007-1203/] 
21

Appendix A. Lead-210 (210Pb) Data from Cores

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–SBLM2A

Core name: Second Bay Lostmans River

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

0–1

1–2A

1–2B

2–3

3–4

4–5

5–6

6–7

7–8

8–9A

8–9B

9–10

10–11

11–12

12–13

13–14

14–15

15–16

16–17

17–18

18–19

19–20

20–22

22–24A

22–24B

24–26

26–28

28–30

30–32

32–34

34–36

36–38

0.5

1.5

1.5

2.5

3.5

4.5

5.5

6.5

7.5

8.5

8.5

9.5

10.5

11.5

12.5

13.5

14.5

15.5

16.5

17.5

18.5

19.5

21.0

23.0

23.0

25.0

27.0

29.0

31.0

33.0

35.0

37.0

12.30

8.71

8.35

11.05

10.50

10.71

11.49

10.85

9.54

9.72

9.54

9.90

9.74

9.54

10.74

11.24

11.73

11.11

10.93

10.12

9.34

10.34

10.28

13.27

13.52

13.44

11.68

10.12

9.31

9.68

--

--

4.95

3.72

3.70

4.29

4.26

4.61

4.45

3.93

3.63

3.46

3.44

3.25

3.14

3.18

2.73

2.42

2.69

2.69

2.62

2.58

2.39

2.44

2.33

3.22

3.18

4.11

4.13

4.32

4.68

4.63

--

--

0.087

0.067

0.064

0.066

0.065

0.071

0.069

0.072

0.060

0.062

0.058

0.055

0.050

0.049

0.041

0.038

0.041

0.051

0.042

0.045

0.036

0.043

0.038

0.061

0.059

0.068

0.063

0.066

0.072

0.071

--

--

2.38

2.50

--

2.97

2.67

2.80

2.67

2.90

3.09

2.87

--

2.92

2.75

2.91

2.76

2.68

2.68

2.75

2.66

2.81

2.84

2.69

--

--

--

--

3.36

--

--

--

--

3.46

0.19

0.09

--

0.16

0.18

0.22

0.15

0.13

0.23

0.17

--

0.19

0.15

0.15

0.18

0.19

0.14

0.15

0.16

0.16

0.13

0.15

--

--

--

--

0.16

--

--

--

--

0.13

ND

ND

--

ND

ND

ND

ND

0.15

ND

ND

--

ND

ND

ND

ND

ND

ND

ND

ND

ND

ND

ND

--

--

--

--

ND

--

--

--

--

ND

--

--

--

--

--

--

--

0.07

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--
22

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–SBLM2A

Core name: Second Bay Lostmans River

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

38–40

40–42

42–44

44–46

46–48

48–50

50–52

52–54

54–56

56–58

58–60

60–62

62–64

64–66

66–68

68–70

70–72

72–74

74–76

76–78

78–80

80–82

82–84

84–86

86–88

88–90

39.0 -- --

41.0 -- --

43.0 -- --

45.0 -- --

47.0 -- --

49.0 -- --

51.0 -- --

53.0 -- --

55.0 -- --

57.0 -- --

59.0 -- --

61.0 -- --

63.0 -- --

65.0 -- --

67.0 -- --

69.0 -- --

71.0 -- --

73.0 -- --

75.0 -- --

77.0 -- --

79.0 -- --

81.0 -- --

83.0 -- --

85.0 -- --

87.0 -- --

89.0 -- --

-- --

-- --

-- --

-- --

-- 3.24

-- --

-- --

-- --

-- --

-- 3.27

-- --

-- --

-- --

-- --

-- 3.37

-- --

-- --

-- --

-- --

-- 3.38

-- --

-- --

-- --

-- --

-- 4.32

-- --

--

--

--

--

0.14

--

--

--

--

0.16

--

--

--

--

0.17

--

--

--

--

0.15

--

--

--

--

0.22

--

-- --

-- --

-- --

-- --

ND --

-- --

-- --

-- --

-- --

ND --

-- --

-- --

-- --

-- --

ND --

-- --

-- --

-- --

-- --

ND --

-- --

-- --

-- --

-- --

ND --

-- --
23

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–FBLM1A

Core name: First Bay Lostmans River

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

0–1

1–2

2–3

3–4A

3–4B

4–5

5–6

6–7

7–8

8–9

9–10

10–11

11–12

12–13

13–14

14–15A

14–15B

15–16

16–17

17–18

18–19

19–20

20–22

22–24A

22–24B

24–26

26–28

28–30

30–32

32–34

34–36

36–38

0.5

1.5

2.5

3.5

3.5

4.5

5.5

6.5

7.5

8.5

9.5

10.5

11.5

12.5

13.5

14.5

14.5

15.5

16.5

17.5

18.5

19.5

21.0

23.0

23.0

25.0

27.0

29.0

31.0

33.0

35.0

37.0

30.48

21.67

7.97

7.33

7.17

9.50

7.94

9.68

8.12

6.52

7.44

6.18

6.55

6.76

8.57

8.32

8.30

10.45

13.21

15.37

14.14

6.53

9.68

13.29

13.19

17.68

18.33

14.09

15.54

16.87

--

--

7.64

6.19

3.41

2.92

2.92

3.41

2.76

2.91

2.71

2.37

2.42

2.08

1.92

1.93

2.27

2.23

2.24

1.93

2.08

1.90

1.81

1.49

1.58

1.63

1.59

1.72

1.58

1.70

1.93

2.08

--

--

0.139

0.117

0.076

0.057

0.054

0.061

0.052

0.055

0.062

0.050

0.050

0.044

0.042

0.040

0.045

0.041

0.043

0.039

0.048

0.041

0.041

0.030

0.033

0.035

0.024

0.040

0.038

0.039

0.042

0.042

--

--

1.75

2.12

3.34

3.02

--

2.94

3.17

3.12

3.65

4.36

2.71

2.33

2.17

1.72

1.55

1.61

--

2.04

1.88

2.09

1.68

1.74

--

--

--

--

--

1.71

--

--

--

--

0.16

0.15

0.16

0.12

--

0.18

0.15

0.18

0.18

0.19

0.12

0.11

0.14

0.09

0.08

0.07

--

0.11

0.11

0.16

0.14

0.10

--

--

--

--

--

0.10

--

--

--

--

0.17

ND

ND

ND

--

ND

ND

ND

ND

ND

ND

ND

ND

ND

ND

ND

--

ND

ND

ND

ND

ND

--

--

--

--

--

ND

--

--

--

--

0.09

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--
24

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–FBLM1A

Core name: First Bay Lostmans River

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

38–40

40–42

42–44

44–46

46–48

48–50

50–52

52–54

54–56

56–58

58–60

60–62

62–64

64–66

66–68

68–70

70–72

72–74

74–76

76–78

78–80

80–82

82–84

84–86

86–88

88–90

90–92

92–94

94–96

96–98

98–100

100–102

39.0 -- --

41.0 -- --

43.0 -- --

45.0 -- --

47.0 -- --

49.0 -- --

51.0 -- --

53.0 -- --

55.0 -- --

57.0 -- --

59.0 -- --

61.0 -- --

63.0 -- --

65.0 -- --

67.0 -- --

69.0 -- --

71.0 -- --

73.0 -- --

75.0 -- --

77.0 -- --

79.0 -- --

81.0 -- --

83.0 -- --

85.0 -- --

87.0 -- --

89.0 -- --

91.0 -- --

93.0 -- --

95.0 -- --

97.0 -- --

99.0 -- --

101.0 -- --

-- 1.80

-- --

-- --

-- --

-- --

-- 1.76

-- --

-- --

-- --

-- --

-- 1.71

-- --

-- --

-- --

-- --

-- 1.96

-- --

-- --

-- --

-- --

-- 1.69

-- --

-- --

-- --

-- --

-- 1.69

-- --

-- --

-- --

-- --

-- 1.96

-- --

0.08

--

--

--

--

0.09

--

--

--

--

0.07

--

--

--

--

0.08

--

--

--

--

0.10

--

--

--

--

0.07

--

--

--

--

0.11

--

ND --

-- --

-- --

-- --

-- --

ND --

-- --

-- --

-- --

-- --

ND --

-- --

-- --

-- --

-- --

ND --

-- --

-- --

-- --

-- --

ND --

-- --

-- --

-- --

-- --

ND --

-- --

-- --

-- --

-- --

ND --

-- --
25

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–FBLM1A

Core name: First Bay Lostmans River

Date collected: July 2005

Depth Mean Loss on Total Pb-210 Total Pb-210 Ra-226 Ra-226 Cs-137 Cs-137

(cm) depth ignition activity error activity error activity error

(cm) (% dry wt.) (dpm/g) +/- (dpm/g) (dpm/g) +/- (dpm/g) (dpm/g) +/- (dpm/g)

102–104 103.0 -- -- -- -- -- -- --

104–106 105.0 -- -- -- -- -- -- --

106–108 107.0 -- -- -- -- -- -- --

108–110 109.0 -- -- -- 2.74 0.12 ND --

110–112 111.0 -- -- -- -- -- --

112–114 113.0 -- -- -- 2.79 0.09 ND --

Core ID: GLW705–HR2A

Core name: Harney River 2A

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

0–1

1–2

2–3

3–4

4–5

5–6

6–7

7–8

8–9

9–10

10–11

11–12

12–13

13–14

14–15

15–16

16–17

17–18

0.5

1.5

2.5

3.5

4.5

5.5

6.5

7.5

8.5

9.5

10.5

11.5

12.5

13.5

14.5

15.5

16.5

17.5

20.91

18.77

21.03

21.35

22.05

22.75

21.76

20.77

20.91

21.26

21.30

21.83

21.74

20.87

19.80

20.79

19.57

20.00

7.72

6.59

7.78

7.37

7.53

7.43

7.35

6.48

6.33

6.43

6.73

6.42

6.13

5.83

5.35

4.79

4.96

5.06

0.165

0.131

0.188

0.166

0.144

0.141

0.143

0.128

0.145

0.131

0.154

0.117

0.124

0.115

0.125

0.103

0.115

0.102

1.85

1.77

1.74

1.95

1.66

1.76

1.62

1.80

1.65

1.69

--

1.74

--

1.56

--

1.34

--

1.44

0.14

0.11

0.12

0.15

0.11

0.15

0.10

0.15

0.14

0.11

--

0.14

--

0.11

--

0.08

--

0.09

ND

Tr?

ND

ND

ND

ND

ND

ND

Tr

0.16

--

ND

--

0.17

--

0.19

--

0.31

--

--

--

--

--

--

--

--

--

0.09

--

--

--

0.07

--

0.05

--

0.07
26

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–HR2A

Core name: Harney River 2A

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

18–19

19–20

20–22

22–24

24–26

26–28

28–30A

28–30B

30–32

32–34

34–36

36–38

38–40

48–50

58–60

68–70

78–80

88–90

96–98

18.5

19.5

21.0

23.0

25.0

27.0

29.0

29.0

31.0

33.0

35.0

37.0

39.0

49.0

59.0

69.0

79.0

89.0

97.0

18.69

19.44

19.32

19.57

19.52

15.16

15.17

14.99

17.30

18.33

20.08

19.80

--

--

--

--

--

--

--

5.06

5.21

4.95

4.90

4.51

3.92

3.68

3.51

4.03

3.03

4.33

4.06

--

--

--

--

--

--

--

0.082

0.095

0.092

0.096

0.105

0.084

0.085

0.069

0.083

0.305

0.136

0.118

--

--

--

--

--

--

--

--

1.59

--

--

--

--

1.61

--

--

--

--

--

1.53

1.47

1.44

1.49

1.60

1.51

1.57

--

0.11

--

--

--

--

0.07

--

--

--

--

--

0.09

0.08

0.08

0.09

0.08

0.08

0.09

--

0.25

--

--

--

--

0.31

--

--

--

--

--

0.25

ND

ND

ND

ND

ND

ND

--

0.07

--

--

--

--

0.05

--

--

--

--

--

0.06

--

--

--

--

--

--

Core ID: GLW705–SHR1A

Core name: Harney River 1A (South Harney, near mouth)

Date collected: July 2005

Depth Mean Loss on Total Pb-210 Total Pb-210 Ra-226 Ra-226 Cs-137 Cs-137

(cm) depth ignition activity error activity error activity error

(cm) (% dry wt.) (dpm/g) +/- (dpm/g) (dpm/g) +/- (dpm/g) (dpm/g) +/- (dpm/g)

0–1 0.5 11.88 3.69 0.101 1.76 0.10 ND --

1–2 1.5 10.47 3.03 0.079 1.94 0.15 ND --

2–3 2.5 12.10 3.42 0.094 2.28 0.16 ND --

3–4 3.5 12.08 3.28 0.082 1.86 0.13 ND --

4–5 4.5 11.90 3.68 0.091 1.98 0.14 Tr? --
27

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–SHR1A

Core name: Harney River 1A (South Harney, near mouth)

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210 Total Pb-210

activity error

(dpm/g) +/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

5–6

6–7

7–8

8–9

9–10

10–11

11–12

12–13

13–14

14–15

15–16A

15–16B

16–17

17–18

18–19

19–20

20–22

22–24

24–26

26–28

28–30A

28–30B

30–32

32–34

34–36

36–38

38–40

48–50

58–60

68–70

5.5

6.5

7.5

8.5

9.5

10.5

11.5

12.5

13.5

14.5

15.5

15.5

16.5

17.5

18.5

19.5

21.0

23.0

25.0

27.0

29.0

29.0

31.0

33.0

35.0

37.0

39.0

49.0

59.0

69.0

11.16

11.46

10.85

10.10

9.07

8.91

8.71

8.93

8.10

7.28

4.72

4.57

4.34

4.53

4.98

10.24

11.51

11.71

12.13

12.25

10.89

10.50

8.55

9.68

10.85

--

--

--

--

--

3.32

3.38

3.03

2.67

2.52

2.30

2.20

2.20

2.24

2.11

1.68

1.74

1.77

1.72

1.63

2.26

2.18

2.21

2.21

2.10

2.00

2.15

1.79

1.78

1.66

--

--

--

--

--

0.079

0.083

0.075

0.078

0.072

0.064

0.055

0.060

0.060

0.064

0.048

0.058

0.053

0.047

0.043

0.060

0.057

0.068

0.061

0.062

0.056

0.063

0.052

0.054

0.048

--

--

--

--

--

2.05

1.75

1.90

1.92

1.72

--

1.91

--

1.71

--

1.58

--

--

1.76

--

1.75

--

--

--

--

1.65

--

--

--

--

--

1.76

1.66

1.59

1.65

0.14

0.12

0.12

0.12

0.11

--

0.09

--

0.09

--

0.10

--

--

0.10

--

0.09

--

--

--

--

0.08

--

--

--

--

--

0.07

0.07

0.09

0.06

ND

ND

0.10

0.17

0.16

--

0.16

--

0.14

--

ND

--

--

Tr

--

0.11

--

--

--

--

ND

--

--

--

--

--

ND

ND

ND

ND

--

--

0.06

0.08

0.06

--

0.06

--

0.05

--

--

--

--

--

--

0.06

--

--

--

--

--

--

--

--

--

--

--

--

--

--
28

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW504–TBB

Core name: Tarpon Bay

Date collected: May 2004

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

†Calc. Excess

Pb-210 activity

(dpm/g)

0–1

1–2

2–3

3–4

4–5

5–6

6–7

7–8

8–9

9–10

10–11

11–12

12–13A

12–13B

12–13C

13–14

14–15

15–16

16–17

17–18

18–19

19–20

20–22

22–24

24–26

26–28A

26–28B

26–28C

28–30

30–32

32–34

0.5

1.5

2.5

3.5

4.5

5.5

6.5

7.5

8.5

9.5

10.5

11.5

12.5

12.5

12.5

13.5

14.5

15.5

16.5

17.5

18.5

19.5

21.0

23.0

25.0

27.0

27.0

27.0

29.0

31.0

33.0

56.09

50.10

42.71

43.31

47.70

52.10

51.10

53.78

53.29

54.09

58.08

56.00

59.68

59.28

57.88

54.89

60.40

61.95

62.87

60.28

62.87

67.27

61.20

57.40

73.00

74.00

74.45

74.45

68.46

68.86

71.46

5.91

2.74

3.28

3.65

3.28

2.25

2.66

2.54

2.18

2.75

1.95

2.57

1.65

1.87

2.05

1.98

1.68

1.81

0.95

1.22

1.54

1.80

1.26

1.66

1.09

1.68

1.04

1.31

1.66

1.83

2.54

0.128

0.058

0.074

0.081

0.078

0.053

0.055

0.056

0.051

0.074

0.054

0.068

0.051

0.052

0.053

0.064

0.052

0.061

0.037

0.038

0.042

0.053

0.038

0.062

0.062

0.073

0.057

0.072

0.071

0.073

0.093

3.27

2.75

2.31

1.95

1.64

1.38

1.16

0.97

0.82

0.69

0.58

0.49

0.41

0.41

0.41

0.35

0.29

0.24

0.21

0.17

0.15

0.12

0.09

0.07

0.05

0.03

0.03

0.03

0.02

0.02

--
29

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW504–TBB

Core name: Tarpon Bay

Date collected: May 2004

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

†Calc. Excess

Pb-210 activity

(dpm/g)

34–36

36–38

38–40

40–42

42–44A

42–44B

44–46

46–48

48–50

50–52

52–54

54–56

56–58

58–60

60–62

62–64

64–65.5

35.0

37.0

39.0

41.0

43.0

43.0

45.0

47.0

49.0

51.0

53.0

55.0

57.0

59.0

61.0

63.0

64.75

78.00

82.80

83.00

81.64

77.80

75.50

80.00

82.83

77.69

72.26

75.20

67.40

55.09

46.81

36.73

27.94

14.34

1.72

2.57

1.56

2.00

2.18

2.07

2.22

1.93

1.31

2.11

4.31

4.04

2.43

3.91

4.00

3.32

2.74

0.069 --

0.101 --

0.063 --

0.064 --

0.068 --

0.066 --

0.070 --

0.084 --

0.060 --

0.056 --

0.100 --

0.096 --

0.067 --

0.161 --

0.105 --

0.077 --

0.067 --

Core ID: GLW705–SR2A

Core name: Shark River 2A (channels)

Date collected: July 2005

Depth Mean Loss on Total Pb-210 Total Pb-210 Ra-226 Ra-226 Cs-137 Cs-137

(cm) depth ignition activity error activity error activity error

(cm) (% dry wt.) (dpm/g) +/- (dpm/g) (dpm/g) +/- (dpm/g) (dpm/g) +/- (dpm/g)

0–1 0.5 27.81 8.79 0.157 1.72 0.16 ND --

1–2 1.5 27.81 9.04 0.148 1.70 0.17 ND --

2–3 2.5 28.40 9.85 0.165 1.56 0.15 Tr (0.15) --

3–4 3.5 30.89 9.90 0.170 1.73 0.19 0.16 0.09

4–5 4.5 32.41 10.06 0.143 1.64 0.16 Tr (0.13) --

5–6 5.5 37.73 9.69 0.146 1.80 0.18 Tr (0.17) --
30

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–SR2A

Core name: Shark River 2A (channels)

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

6–7

7–8

8–9

9–10

10–11

11–12

12–13

13–14

14–15

15–16

16–17

17–18

18–19

19–20

20–22

22–24

24–26

26–28

28–30A

28–30B

30–32

32–34

34–36

36–38

38–40

48–50

58–60

68–70

78–80

88–90

98–100

6.5

7.5

8.5

9.5

10.5

11.5

12.5

13.5

14.5

15.5

16.5

17.5

18.5

19.5

21.0

23.0

25.0

27.0

29.0

29.0

31.0

33.0

35.0

37.0

39.0

49.0

59.0

69.0

79.0

89.0

99.0

33.82

32.02

31.35

30.69

28.74

28.23

24.85

26.64

24.26

23.41

22.66

21.78

24.01

25.25

23.96

25.44

23.66

22.18

22.97

21.58

21.71

21.98

21.78

22.33

--

--

--

--

--

--

--

10.96

9.66

9.80

8.83

8.27

5.26

5.07

4.79

4.70

4.32

3.67

3.54

2.94

2.52

2.23

2.48

2.23

2.15

2.10

2.13

2.14

2.23

2.22

2.23

2.47

2.53

2.68

2.51

2.57

2.63

2.98

0.166

0.145

0.174

0.142

0.176

0.116

0.117

0.103

0.101

0.085

0.078

0.077

0.077

0.062

0.058

0.063

0.058

0.052

0.048

0.054

0.051

0.052

0.048

0.045

0.341

0.316

0.304

0.342

0.361

0.383

0.816

1.55

1.78

1.71

1.80

1.65

1.98

1.68

1.69

1.69

1.78

1.90

1.82

1.83

1.88

1.85

1.66

--

1.71

--

--

1.78

--

1.66

--

1.65

1.85

1.80

2.03

1.86

1.90

2.11

0.16

0.15

0.16

0.18

0.10

0.13

0.13

0.13

0.10

0.15

0.12

0.12

0.10

0.13

0.11

0.10

--

0.11

--

--

0.11

--

0.08

--

0.10

0.10

0.07

0.14

0.13

0.10

0.21

Tr (0.18)

ND

0.16

0.16

0.19

0.28

0.24

0.22

0.26

0.21

0.24

0.22

0.17

ND

ND

ND

--

ND

--

--

ND

--

ND

--

ND

ND

ND

ND

ND

ND

ND

--

--

0.07

0.07

0.06

0.08

0.06

0.06

0.06

0.07

0.08

0.08

0.07

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--
31

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–SR2A

Core name: Shark River 2A (channels)

Date collected: July 2005

Depth Mean Loss on Total Pb-210 Total Pb-210 Ra-226 Ra-226 Cs-137 Cs-137

(cm) depth ignition activity error activity error activity error

(cm) (% dry wt.) (dpm/g) +/- (dpm/g) (dpm/g) +/- (dpm/g) (dpm/g) +/- (dpm/g)

108–110 109.0 -- 0.84 0.270 0.84 0.08 ND --

118–120 119.0 -- 1.03 0.209 0.71 0.06 ND --

128–130 129.0 -- 1.00 0.236 0.83 0.09 ND --

138–140 139.0 -- 1.03 0.194 0.74 0.07 ND --

Core ID: GLW705–SR1A

Core name: Shark River 1A (near mouth)

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210 Total Pb-210

activity error

(dpm/g) +/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

0–1

1–2

2–3

3–4

4–5

5–6

6–7

7–8

8–9A

8–9B

9–10

10–11

11–12

12–13

13–14

14–15

15–16A

15–16B

16–17

17–18

0.5

1.5

2.5

3.5

4.5

5.5

6.5

7.5

8.5

8.5

9.5

10.5

11.5

12.5

13.5

14.5

15.5

15.5

16.5

17.5

15.90

8.96

10.50

10.52

10.28

11.51

11.51

10.18

8.96

9.36

10.91

12.55

13.35

10.12

8.86

9.16

9.54

9.11

8.55

9.16

5.03

3.23

3.99

4.09

3.72

3.88

3.65

3.13

3.07

3.07

3.19

3.23

3.42

2.98

2.62

2.55

2.59

2.45

2.39

2.50

0.130

0.082

0.107

0.123

0.119

0.099

0.100

0.088

0.088

0.077

0.081

0.079

0.079

0.074

0.068

0.065

0.075

0.066

0.063

0.062

1.59

1.59

1.44

1.44

1.53

1.53

1.62

1.67

1.52

--

1.49

--

1.53

--

1.65

--

1.45

--

--

1.58

0.13

0.11

0.09

0.07

0.08

0.12

0.10

0.10

0.08

--

0.09

--

0.09

--

0.09

--

0.08

--

--

0.08

ND

ND

ND

Tr

ND

ND

Tr

ND

ND

--

Tr

--

ND

--

ND

--

0.08

--

--

ND

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

0.04

--

--

--
32

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW705–SR1A

Core name: Shark River 1A (near mouth)

Date collected: July 2005

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Ra-226

activity

(dpm/g)

Ra-226

error

+/- (dpm/g)

Cs-137

activity

(dpm/g)

Cs-137

error

+/- (dpm/g)

18–19

19–20

20–22

22–24A

22–24B

24–26

26–28

28–30

30–32

32–34

18.5

19.5

21.0

23.0

23.0

25.0

27.0

29.0

31.0

33.0

8.13

7.97

7.91

7.36

7.51

5.93

5.15

5.78

7.34

6.92

2.21

2.21

2.14

2.00

2.18

1.85

1.83

1.70

1.82

1.75

0.063

0.062

0.049

0.042

0.051

0.040

0.041

0.039

0.043

0.036

--

1.66

--

--

--

--

--

--

--

--

--

0.10

--

--

--

--

--

--

--

--

-- --

Tr --

-- --

-- --

-- --

-- --

-- --

-- --

-- --

-- --

Core ID: GLW504–RRB

Core name: Roberts River (near mouth)

Date collected: May 2004

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Calc. Excess

Pb-210 activity

(dpm/g)

0–1

1–2

2–3

3–4

4–5

5–6

6–7

7–8

8–9

9–10

10–11A

10–11B

10–11C

11–12

0.5

1.5

2.5

3.5

4.5

5.5

6.5

7.5

8.5

9.5

10.5

10.5

10.5

11.5

35.13

27.89

27.09

25.90

25.55

25.90

25.55

24.95

28.69

28.29

29.00

27.80

29.74

31.60

7.84

5.70

5.90

5.83

5.40

4.89

4.90

4.29

5.77

3.86

3.23

3.25

3.04

3.02

0.171

0.110

0.108

0.110

0.101

0.090

0.107

0.081

0.104

0.077

0.070

0.066

0.072

0.085

6.43

5.94

5.48

5.06

4.67

4.31

3.98

3.67

3.39

3.13

2.89

2.89

2.89

2.67
33

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW504–RRB

Core name: Roberts River (near mouth)

Date collected: May 2004

Depth

(cm)

Mean

depth

(cm)

Loss on

ignition

(% dry wt.)

Total Pb-210

activity

(dpm/g)

Total Pb-210

error

+/- (dpm/g)

Calc. Excess

Pb-210 activity

(dpm/g)

12–13

13–14

14–15

15–16

16–17

17–18

18–19

19–20

20–22

22–24

24–26

26–28

28–30A

28–30B

28–30C

30–32

32–34

34–36

36–38

38–40

40–42

42–44

44–46

46–48

48–50A

48–50B

48–50C

50–52

52–54

54–56

56–58

12.5

13.5

14.5

15.5

16.5

17.5

18.5

19.5

21.0

23.0

25.0

27.0

29.0

29.0

29.0

31.0

33.0

35.0

37.0

39.0

41.0

43.0

45.0

47.0

49.0

49.0

49.0

51.0

53.0

55.0

57.0

31.34

26.80

24.35

22.80

30.00

29.60

27.54

27.15

25.75

18.40

13.35

11.98

10.80

11.16

11.16

11.58

10.36

8.58

10.40

8.96

8.60

7.00

9.20

10.58

6.80

6.80

6.40

8.40

7.19

5.99

10.38

2.90

3.79

3.04

2.89

2.77

2.65

2.69

2.41

2.73

2.42

1.86

1.22

0.84

0.92

0.85

0.92

0.91

0.77

0.64

0.75

0.61

0.62

0.61

0.53

0.55

0.57

0.46

0.65

0.78

0.84

1.44

0.072

0.101

0.079

0.079

0.068

0.060

0.076

0.062

0.079

0.105

0.072

0.038

0.035

0.030

0.033

0.035

0.042

0.032

0.027

0.027

0.026

0.028

0.027

0.020

0.027

0.030

0.021

0.029

0.030

0.025

0.052

2.46

2.27

2.10

1.94

1.79

1.65

1.52

1.41

1.25

1.06

0.91

0.77

0.66

0.66

0.66

0.56

0.48

0.41

0.35

0.30

0.25

0.21

0.18

0.16

0.13

0.13

0.13

0.11

0.10

0.08

0.07
34

Appendix A. Lead-210 (210Pb) Data from Cores—Continued

[cm, centimeters; dpm/g, disintegrations per minute per gram; % dry wt., percent dry weight; ND, not detected; Tr, 

trace quantity, too low to quantify; calc., calculated]

Core ID: GLW504–RRB

Core name: Roberts River (near mouth)

Date collected: May 2004

Depth Mean Loss on Total Pb-210 Total Pb-210 Calc. Excess

(cm) depth ignition activity error Pb-210 activity

(cm) (% dry wt.) (dpm/g) +/- (dpm/g) (dpm/g)

58–60 59.0 7.37 0.82 0.030 0.06

60–62 61.0 9.00 0.69 0.022 0.05

62–64 63.0 9.78 0.62 0.020 0.04

64–66 65.0 10.18 0.60 0.020 0.04

66–68 67.0 11.20 0.70 0.022 0.03

68–70 69.0 8.58 0.74 0.023 0.03

70–72 71.0 6.57 0.88 0.030 0.02

72–74 73.0 5.40 1.55 0.054 0.02
35

Appendix B. Pollen Diagrams

[cm, centimeters] 

GLW504–TBA

 Percent abundance

Percent abundance pollen for GLW504–TBA
36

Appendix B. Pollen Diagrams—Continued

[cm, centimeters]

GLW705–HR2A

 Percent abundance

Percent abundance pollen for GLW705–HR2A
37

Appendix B. Pollen Diagrams—Continued

[cm, centimeters]

GLW705–SHR1A

 Percent abundance

Percent abundance pollen for GLW705–SHR1A
38

Appendix B. Pollen Diagrams—Continued

[cm, centimeters]

GLW705–SR2A

 Percent abundance

Percent abundance pollen for GLW705–SR2A
39

Appendix B. Pollen Diagrams—Continued

[cm, centimeters]

GLW705–SR1A

 Percent abundance

Percent abundance pollen for GLW705–SR1A
40

Appendix B. Pollen Diagrams—Continued

[cm, centimeters]

GLW504–RRB

 Percent abundance

Percent abundance pollen for GLW504–RRB
41

Appendix C. Calibrated Age Ranges (Intcal09)

Calibrated data points were used to constrain the age models. Year 0 = CE 1950. 

[cm, centimeters; min., minimum; max., maximum]

Core

Sample depth 

(cm)

Sample 

type Min. year Max. year Probability

GLW705–SBLM2A 2 surface -56 -53 95

10 lead-210 -19 19 95

29 carbon-14 976 1178 93.9

29 carbon-14 1214 1222 1.1

77 carbon-14 2164 2166 0.3

77 carbon-14 2179 2241 15.7

77 carbon-14 2302 2460 79

109 carbon-14 4159 4170 2

109 carbon-14 4178 4201 4.7

109 carbon-14 4226 4419 88.3

GLW705–FBLM1A 2 surface 48 51 95

35 carbon-14 -1 42 16.7

35 carbon-14 59 154 32.4

35 carbon-14 167 234 28.6

35 carbon-14 236 284 17.2

53 carbon-14 -5 -3 0.9

53 carbon-14 23 142 69

53 carbon-14 218 265 25

83 carbon-14 13 148 66.5

83 carbon-14 188 198 1.6

83 carbon-14 204 205 0.2

83 carbon-14 211 269 26.6

109 carbon-14 298 477 95

GLW504–TBA 1 surface -56 -53 95

11 lead-210 -19 19 95

13 carbon-14 -3 12 3.9

13 carbon-14 149 187 13.9

13 carbon-14 209 210 0.2

13 carbon-14 270 336 40.4

13 carbon-14 348 458 36.6

27 carbon-14 536 653 95

35 carbon-14 1173 1299 95

43 carbon-14 1296 1403 95

51 carbon-14 1082 1114 8

51 carbon-14 1119 1164 13.3
42

Appendix C. Calibrated Age Ranges (Intcal09)—

Continued

Calibrated data points were used to constrain the age models. Year 0 = CE 1950. 

[cm, centimeters; min., minimum; max., maximum]

Core

Sample depth 

(cm)

Sample 

type Min. year Max. year Probability

GLW504–TBA 51

81

81

carbon-14

carbon-14

carbon-14

1166

3646

3687

1282

3658

3876

73.6

1.7

93.3

GLW705–SR2A 1

15

15

15

15

18

21

37

37

37

67

67

87

87

87

103

103

103

103

surface

carbon-14

carbon-14

carbon-14

carbon-14

cesium

pollen

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

-56

-1

59

167

236

-19

21

690

808

852

557

626

1005

1052

1200

3935

3973

4168

4199

-53

42

154

234

284

19

78

803

831

905

604

686

1030

1188

1260

3936

4161

4179

4229

95

16.7

32.4

28.6

17.2

95

95

71.7

6.2

17.1

38.6

56.3

4.2

77.6

13.2

0.2

88.6

1.4

4.8

GLW705–SR1A 1

22

61

45

45

45

45

45

63

101

101

101

101

101

surface

lead-210

pollen

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14

carbon-14 (1

carbon-14 (2

carbon-14 (2

carbon-14 (2

carbon-14 (2

-56

-19

21

-4

68

131

244

251

670

674

-1

59

167

236

-53

19

78

35

117

230

248

301

775

789

42

154

234

284

95

95

95

17.8

9.5

47.4

0.6

19.7

95

95

16.7

32.4

28.6

17.2
43

Core

Sample depth 

(cm)

Sample 

type Min. year Max. year Probability

GLW504–LMA 1 surface -56 -53 95

21 carbon-14 1064 1264 95

47 carbon-14 2348 2543 70.7

47 carbon-14 2564 2569 0.6

47 carbon-14 2587 2616 6

47 carbon-14 2636 2699 17.7

Appendix C. Calibrated Age Ranges (Intcal09)—

Continued

Calibrated data points were used to constrain the age models. Year 0 = CE 1950. 

[cm, centimeters; min., minimum; max., maximum]
44

Appendix D. Age Model by Core 

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW705–SBLM2A 2 -56 -52 -54

3 -50 -45 -47

4 -45 -36 -41

5 -40 -26 -34

6 -36 -17 -27

7 -32 -8 -20

8 -27 2 -14

9 -23 11 -7

10 -19 20 0

11 38 77 57

12 93 136 115

13 147 197 172

14 200 259 230

15 252 320 287

16 304 383 345

17 356 445 402

18 407 507 460

19 458 569 518

20 509 631 575

21 560 693 633

22 612 756 690

23 663 819 748

24 714 881 805

25 764 943 863

26 815 1006 920

27 866 1069 978

28 918 1132 1035

29 968 1194 1093

30 996 1218 1119

31 1025 1242 1145

32 1053 1266 1170

33 1081 1290 1196

34 1109 1315 1222

35 1137 1340 1247

36 1165 1366 1273

37 1193 1391 1299
45

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW705–SBLM2A 38 1221 1418 1325

39 1248 1443 1350

40 1275 1469 1376

41 1303 1495 1402

42 1330 1521 1428

43 1357 1547 1453

44 1384 1573 1479

45 1411 1599 1505

46 1437 1625 1531

47 1464 1651 1556

48 1489 1676 1582

49 1513 1701 1608

50 1538 1726 1634

51 1563 1752 1659

52 1587 1777 1685

53 1610 1801 1711

54 1634 1826 1737

55 1658 1852 1762

56 1682 1878 1788

57 1706 1904 1814

58 1730 1930 1840

59 1754 1956 1865

60 1778 1983 1891

61 1803 2010 1917

62 1827 2037 1943

63 1851 2064 1968

64 1871 2095 1994

65 1895 2125 2020

66 1918 2155 2046

67 1941 2183 2071

68 1964 2211 2097

69 1988 2239 2123

70 2010 2268 2148

71 2033 2296 2174

72 2057 2324 2200

73 2081 2352 2226
46

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW705–SBLM2A 74 2106 2381 2251

75 2130 2409 2277

76 2153 2437 2303

77 2176 2466 2329

78 2241 2524 2391

79 2304 2581 2453

80 2369 2640 2515

81 2437 2697 2577

82 2503 2754 2639

83 2568 2811 2701

84 2634 2869 2763

85 2703 2924 2825

86 2768 2984 2887

87 2832 3045 2949

88 2897 3106 3011

89 2962 3167 3074

90 3026 3228 3136

91 3090 3288 3198

92 3155 3350 3260

93 3219 3412 3322

94 3283 3474 3384

95 3347 3535 3446

96 3409 3596 3508

97 3470 3657 3570

98 3531 3719 3632

99 3592 3782 3694

100 3651 3844 3756

101 3710 3908 3818

102 3769 3972 3881

103 3827 4035 3943

104 3886 4099 4005

105 3944 4163 4067

106 4003 4228 4129

107 4061 4292 4191

108 4119 4358 4253

109 4177 4423 4315
47

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW705–FBLM1A 2 48 51 50

3 50 56 53

4 51 62 55

5 50 67 58

6 50 72 61

7 50 78 63

8 50 84 66

9 50 90 69

10 50 96 72

11 50 102 74

12 50 108 77

13 49 113 80

14 49 119 82

15 49 125 85

16 49 131 88

17 48 136 90

18 49 143 93

19 49 149 96

20 48 154 98

21 49 161 101

22 48 166 104

23 48 172 107

24 48 177 109

25 48 183 112

26 48 189 115

27 48 195 117

28 48 201 120

29 48 207 123

30 48 213 125

31 47 218 128

32 48 225 131

33 47 230 134

34 47 236 136

35 46 241 139

36 49 242 140

37 51 243 142
48

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW705–FBLM1A 38 53 243 143

39 55 244 144

40 57 245 146

41 58 245 147

42 60 246 149

43 61 246 150

44 62 246 151

45 64 247 153

46 65 248 154

47 65 247 156

48 67 249 157

49 67 248 158

50 69 250 160

51 69 250 161

52 71 251 162

53 71 251 164

54 72 252 165

55 72 252 167

56 73 253 168

57 75 254 169

58 75 254 171

59 75 254 172

60 77 256 174

61 77 257 175

62 77 257 176

63 78 258 178

64 78 258 179

65 79 259 180

66 80 260 182

67 80 261 183

68 79 262 185

69 79 264 186

70 78 265 187

71 78 267 189

72 78 268 190

73 78 270 192
49

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW705–FBLM1A 74 78 271 193

75 78 273 194

76 78 274 196

77 79 276 197

78 79 278 198

79 79 279 200

80 79 280 201

81 79 282 203

82 79 284 204

83 80 287 205

84 91 290 212

85 103 295 219

86 115 300 226

87 127 303 233

88 140 308 239

89 152 314 246

90 163 321 253

91 173 328 260

92 183 335 267

93 191 342 273

94 202 351 280

95 211 359 287

96 220 367 294

97 228 375 301

98 237 384 308

99 244 391 314

100 250 399 321

101 256 407 328

102 262 416 335

103 265 423 342

104 270 432 348

105 273 440 355

106 277 449 362

107 281 459 369

108 284 468 376

109 287 478 382
50

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW504–TBA 1 -56 -52 -54

2 -51 -47 -49

3 -48 -40 -43

4 -43 -32 -38

5 -40 -25 -33

6 -36 -17 -27

7 -33 -10 -22

8 -30 -3 -16

9 -26 5 -11

10 -22 13 -6

11 -19 20 0

12 61 240 156

13 4 475 312

14 47 484 332

15 91 494 352

16 223 503 372

17 255 512 392

18 288 520 413

19 317 532 433

20 347 545 453

21 375 556 473

22 405 569 493

23 435 582 513

24 464 597 533

25 490 613 554

26 513 632 574

27 531 655 594

28 619 728 674

29 703 804 755

30 785 883 835

31 864 963 915

32 941 1046 996

33 1020 1131 1076

34 1095 1217 1156

35 1168 1305 1236

36 1189 1312 1250
51

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW504–TBA 37 1207 1320 1264

38 1224 1329 1278

39 1240 1340 1291

40 1257 1353 1305

41 1271 1366 1319

42 1283 1383 1332

43 1292 1403 1346

44 1357 1465 1410

45 1422 1527 1474

46 1486 1590 1538

47 1550 1652 1601

48 1615 1716 1665

49 1679 1779 1729

50 1742 1842 1793

51 1806 1906 1857

52 1870 1970 1921

53 1933 2034 1984

54 1996 2098 2048

55 2060 2163 2112

56 2124 2228 2176

57 2187 2293 2240

58 2250 2358 2303

59 2312 2422 2367

60 2374 2487 2431

61 2437 2552 2495

62 2500 2618 2559

63 2562 2683 2622

64 2624 2749 2686

65 2686 2814 2750

66 2748 2880 2814

67 2810 2946 2878

68 2872 3013 2942

69 2934 3079 3005

70 2995 3145 3069

71 3056 3211 3133

72 3118 3278 3197
52

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Core

Sample depth 

(cm) Min 95% Max 95% Best

GLW504–TBA 73

74

75

76

77

78

79

80

81

3180

3242

3304

3365

3427

3489

3550

3612

3674

3345

3412

3479

3546

3613

3680

3747

3814

3881

3261

3324

3388

3452

3516

3580

3644

3707

3771

GLW705–SR2A 1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

-56

-53

-51

-48

-45

-43

-41

-39

-37

-35

-33

-30

-28

-27

-25

-23

-21

-19

2

14

22

35

47

60

72

85

97

-52

-50

-46

-42

-37

-33

-29

-25

-20

-16

-12

-7

-3

1

5

9

13

17

33

54

79

91

102

115

127

140

152

-54

-51

-48

-45

-41

-38

-35

-32

-29

-26

-22

-19

-16

-13

-10

-6

-3

0

17

34

50

63

75

88

100

113

125
53

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW705–SR2A 28 110 165 138

29 122 178 150

30 134 190 163

31 146 203 175

32 159 217 188

33 170 229 200

34 183 243 213

35 193 255 226

36 206 269 238

37 217 281 251

38 229 294 263

39 241 308 276

40 253 321 288

41 265 335 301

42 276 347 313

43 287 360 326

44 298 373 338

45 310 387 351

46 322 400 363

47 333 413 376

48 345 428 388

49 355 442 401

50 366 455 413

51 377 469 426

52 388 483 438

53 399 497 451

54 409 510 463

55 421 524 476

56 431 538 488

57 443 552 501

58 453 565 513

59 464 579 526

60 476 594 538

61 487 608 551

62 497 621 563

63 508 635 576
54

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW705–SR2A 64 519 649 588

65 530 663 601

66 541 677 613

67 552 691 626

68 580 713 651

69 608 736 676

70 637 757 701

71 662 782 726

72 688 810 751

73 713 838 776

74 738 866 801

75 763 895 826

76 788 925 851

77 811 953 876

78 833 982 901

79 854 1011 926

80 874 1041 951

81 893 1070 976

82 912 1100 1001

83 931 1130 1026

84 946 1163 1051

85 961 1194 1076

86 979 1227 1101

87 996 1258 1126

88 1191 1435 1311

89 1385 1612 1495

90 1584 1789 1680

91 1775 1969 1864

92 1964 2149 2049

93 2151 2329 2233

94 2336 2510 2418

95 2521 2694 2602

96 2702 2878 2787

97 2882 3064 2971

98 3061 3251 3156

99 3242 3443 3341
55

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Core

Sample depth 

(cm) Min 95% Max 95% Best

GLW705–SR2A 100

101

102

103

3424

3605

3785

3964

3639

3835

4033

4229

3525

3710

3894

4079

GLW705–SR1A 1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

-56

-53

-51

-48

-47

-45

-44

-42

-40

-39

-37

-35

-34

-32

-31

-29

-27

-25

-23

-22

-20

-19

-12

-8

-8

-7

-7

-6

-6

-6

-6

-6

-52

-50

-47

-43

-40

-36

-33

-30

-26

-23

-19

-15

-12

-8

-5

-2

2

6

10

13

17

20

28

38

47

58

70

82

95

107

120

133

-54

-51

-49

-46

-44

-41

-38

-36

-33

-31

-28

-26

-23

-20

-18

-15

-13

-10

-7

-5

-2

0

7

14

21

28

35

41

48

55

62

69
56

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW705–SR1A 33 -6 146 76

34 -8 159 83

35 -8 173 89

36 -9 187 96

37 -10 200 103

38 -10 214 110

39 -11 227 117

40 -12 240 124

41 -13 254 131

42 -14 267 137

43 -14 280 144

44 -15 294 151

45 -16 307 158

46 -12 291 151

47 -7 276 145

48 -3 259 138

49 1 243 131

50 6 227 124

51 10 211 118

52 14 194 111

53 18 179 104

54 21 165 98

55 24 150 91

56 26 135 84

57 28 121 78

58 31 108 71

59 31 95 64

60 28 85 58

61 22 79 51

62 24 81 53

63 27 85 56

64 28 88 58

65 30 93 61

66 30 96 63

67 30 100 65

68 31 105 68
57

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Core

Sample depth 

(cm) Min 95% Max 95% Best

GLW705–SR1A 69

70

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

97

98

99

100

101

30

31

31

30

30

29

28

28

26

25

24

23

23

21

20

19

18

17

16

15

13

12

10

10

9

7

6

4

3

2

0

0

-2

109

114

119

124

129

134

139

145

149

155

160

165

172

177

182

188

194

199

205

211

216

222

227

234

240

245

251

257

263

269

274

281

286

70

73

75

78

80

83

85

87

90

92

95

97

100

102

105

107

109

112

114

117

119

122

124

126

129

131

134

136

139

141

144

146

148

GLW504–LMA 1

2

3

-57

2

58

-53

12

78

-54

7

68
58

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW504–LMA 4 114 145 129

5 169 210 190

6 225 277 250

7 281 343 311

8 337 410 372

9 393 476 433

10 448 542 494

11 504 609 555

12 560 675 616

13 616 742 677

14 671 807 737

15 727 874 798

16 782 940 859

17 839 1007 920

18 894 1073 981

19 950 1139 1042

20 1006 1206 1103

21 1062 1273 1164

22 1116 1321 1214

23 1169 1370 1265

24 1220 1419 1316

25 1271 1469 1367

26 1322 1520 1418

27 1373 1572 1469

28 1424 1625 1520

29 1474 1678 1571

30 1524 1732 1622

31 1574 1786 1673

32 1624 1841 1724

33 1674 1896 1775

34 1723 1950 1825

35 1772 2006 1876

36 1822 2062 1927

37 1870 2118 1978

38 1918 2174 2029

39 1967 2231 2080
59

Appendix D. Age Model by Core—Continued

Output from age model. Year 0 = CE 1950. 

[cm, centimeters; min, minimum; max, maximum]

Sample depth 

Core (cm) Min 95% Max 95% Best

GLW504–LMA 40 2013 2291 2131

41 2058 2350 2182

42 2105 2410 2233

43 2150 2469 2284

44 2196 2528 2335

45 2241 2586 2385

46 2288 2646 2436

47 2333 2705 2487