In cooperation with the Geological Survey of Bangladesh and Bangladesh Water 

Development Board 

Compositional Data for Bengal Delta Sediment Collected 

from a Borehole at Rajoir, Bangladesh 

By George N. Breit, James C. Yount, Md. Nehal Uddin, Ad. Atual Muneem, Heather A. Lowers, Cyrus J. 

Berry, and John W. Whitney 

Open-File Report 2007–1022 

U.S. Department of the Interior 

U.S. Geological Survey 
ii

U.S. Department of the Interior 

DIRK KEMPTHORNE, Secretary 

U.S. Geological Survey 

Mark D. Myers, Director 

U.S. Geological Survey, Reston, Virginia 2007 

For product and ordering information: 

World Wide Web: http://www.usgs.gov/pubprod 

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its natural and living resources, natural hazards, and the environment: 

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Suggested citation: 

Breit, G.N., Yount, J.C., Uddin, Md. N., Muneem, Ad., A., Lowers, H.A., Berry, C.J., and Whitney, J.W., 2007, 

Compositional data for Bengal delta sediment collected from boreholes at Rajoir, Bangladesh: U.S. 

Geological Survey Open-File Report 2007-1022. 

Any use of trade, product, or firm names is for descriptive purposes only and does not 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 

Setting...............................................................................................................................................................................2

Methods...................................................................................................................................................................................2 

Sample collection ...........................................................................................................................................................2 

Grain-size analysis .........................................................................................................................................................3 

Mineralogy.......................................................................................................................................................................4 

Bulk Chemical Analyses ................................................................................................................................................4 

Chemical Extraction Analyses......................................................................................................................................4 

Results......................................................................................................................................................................................5 

Physical and Mineralogical Characteristics .............................................................................................................5 

Bulk Chemical Composition ..........................................................................................................................................6 

Chemical Extractions ...................................................................................................................................................10 

References Cited..................................................................................................................................................................11 

 Figures 

1. Location of Rajoir, Bangladesh ...................................................................................................................................3 

2. Ternary diagram of sand, silt and clay abundances................................................................................................6 

3. Plot of potassium vs. barium in Rajoir sediment.......................................................................................................7 

4. Comparison of measured and corrected sulfur concentrations ...........................................................................8 

Table 

1. Median, minimum, and maximum concentrations of chemical constituents.....................................................9

Appendices 

1. Depth and description of air-dried sediment samples............................................................................................14 

2. Depth of preserved sediment samples ......................................................................................................................15 

3. Results of grain-size analysis ......................................................................................................................................16 

4. Major minerals present in air-dried sediment samples as determined by X-ray diffraction...........................17 

5. Results of quantitative mineralogical analysis of air-dried sediments using X-ray diffraction ......................18 

6. Results of carbon and sulfur analysis of air-dried samples...................................................................................19 

7. Results of ICP-AES analyses of air-dried samples..................................................................................................20 

8. Results of EDXRF analysis of air-dried samples.......................................................................................................26 

9. Results of arsenic analyses by HGAAS of air-dried samples................................................................................32 

10. Total iron and ferrous iron extracted by 0.5 N HCl from preserved sediment samples...................................33 

11. Results of analyses of 0.5 N HCl extract solutions from preserved sediment samples...................................34 

12. Concentrations of acid-volatile sulfide, reducible sulfide and acid-soluble sulfate........................................40 
iv

SI to Inch/Pound 

Multiply By To obtain 

Length 

centimeter (cm) 0.3937 inch (in.) 

millimeter (mm) 0.03937 inch (in.) 

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi) 

kilometer (km) 0.5400 mile, nautical (nmi) 

meter (m) 1.094 yard (yd) 

Volume 

milliliter 0.03382 ounce, fluid (fl. oz) 

milliliter 0.002113 pint (pt) 

milliliter 0.001057 quart (qt) 

milliliter 0.06102 cubic inch (in3) 

Mass 

gram (g) 0.03527 ounce, avoirdupois (oz) 

kilogram (kg) 2.205 pound avoirdupois (lb) 

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows: 

°F=(1.8×°C)+32 

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows: 

°C=(°F-32)/1.8 

Horizontal coordinate information is referenced to World Geodetic System 1984 (WGS 84) 
v

Chemical Symbols 

Abbreviation Chemical Species 

Ag silver 

Al aluminum 

As arsenic 

Au gold 

B boron 

Ba barium 

Be beryllium 

Bi bismuth 

C carbon 

C-total total carbon 

C-carbonate carbonate carbon 

Ca calcium 

Cd cadmium 

Ce cerium 

Co cobalt 

Cr chromium 

Cu copper 

Cs cesium 

Eu europium 

Fe iron 

Ga gallium 

Ge germanium 

Ho holmium 

K potassium 

La lanthanum 

Li lithium 

Mg magnesium 

Mn manganese 

Mo molybdenum 

Na sodium 

Nb niobium 

Nd neodymium 

Ni nickel 

P phosphorous 

Pb lead 

Rb rubidium 

S sulfur 

Sb antimony 

Sc scandium 

Se selenium 

SiO2 silicon dioxide (silica) 

Sn tin 

Sr strontium 
Abbreviation Chemical Species 

Ta tantalum 

Th thorium 

Ti titanium 

U uranium 

V vanadium 

W tungsten 

Y yttrium 

Yb ytterbium 

Zn zinc 

Zr zirconium 

vi
Compositional Data for Bengal Delta Sediment 

Collected from a Borehole at Rajoir, Bangladesh 

By George N. Breit, James C. Yount, Md. Nehal Uddin, Ad. Atual Muneem, Heather A. Lowers, Cyrus 

J. Berry, and John W. Whitney 

Abstract 

Processes active within sediment of the Bengal basin have attracted world concern because of the 

locally high content of arsenic dissolved in ground water drawn from that sediment. Sediment 

samples were collected from a borehole in the town of Rajoir, Rajoir upazila, Madaripur district, 

Bangladesh, to investigate the processes contributing to arsenic contamination. The samples were 

mineralogically and chemically analyzed to determine compositional variations related to the 

arsenic content of the sediment. Mineralogy of the sediment was determined using powder X-ray 

diffraction. Bulk chemical composition was measured by Combustion; Inductively Coupled 

Plasma Atomic Emission Spectroscopy; Energy Dispersive X-ray Fluorescence; and Hydride 

Generation Atomic Absorption Spectrophotometry. Sediment was treated with 0.5 N HCl and 

resulting solutions were analyzed, primarily to evaluate the abundance and oxidation state of acidsoluble iron. Acid-volatile sulfide, acid-soluble sulfate, and reducible sulfide were also measured 

on a few samples. Sediment sampled at Rajoir is typically unlithified, gray, micaceous, feldspathic 

arenaceous sand with a few silt and clay layers. Arsenic content of the sediment ranges from 0.6 to 

21 ppm with a median of 1.2 ppm. 

Introduction 

The ingestion of arsenic-rich ground water was first proposed as the cause for a range of health 

problems experienced by residents of the Bengal basin in India in 1983 (Gorair and others, 1984; 

Saha, 1984; 1995). Subsequent testing of wells across the basin has determined that ground water 

locally contains high concentrations of arsenic. An estimated 40 million residents (20% of the 

population) consume water that exceeds the local arsenic drinking water standard of 50 μg/L 

(World Bank, 2005). In addition, this contaminated water is used to irrigate agricultural land 

needed to supply food for an increasing population. Explanations for the contamination have 

generally proposed that naturally occurring arsenic is released from ferric oxyhydroxide grain 

coatings in response to microbially facilitated reduction in the subsurface (Nickson and others, 

2000; Smedley and Kinniburgh, 2002; Harvey and others, 2002; Horneman and others, 2004; 

Ravenscroft and others, 2005). This report presents the results of characterization of sediment 

samples in south-central Bangladesh within the town of Rajoir (fig. 1). 

A primary concern for aid agencies that seek to alleviate the health crisis caused by the 

consumption of arsenic-rich water is to identify methods to supply safe drinking water. One of the 

proposed mitigation strategies is to install water wells to depths below 150 m. Water analyses 

1
summarized in the National Arsenic Mitigation Information Center (NAMIC) and other databases 

(www.bamwsp.org) show that the frequency of wells that produce water exceeding the drinking 

water standard decrease with increasing depth. Although the lack of arsenic in water produced by 

these deeper wells has been attributed to removal of arsenic in the sediment by ground-water flow, 

no evidence has been offered to verify the loss of arsenic. This investigation determined the 

composition of sediment from depths as great as 450 meters to provide the data to support an 

evaluation of the viability of deeper aquifers to sustain production of water with low arsenic 

contents. Funding support for USGS work on this project was provided by the U.S. Agency for 

International Development. 

Setting 

The village of Rajoir is located approximately 65 kilometers southwest of the capital city of Dhaka 

in Rajoir upazila, Madaripur District (fig. 1). Testing of 13,000 tubewells in the Rajoir upazila 

determined that more than 75% produce water containing dissolved arsenic concentrations greater 

than 50 μg/L (www.bamwsp.org). Rajoir is 50 km west of the Meghna Estuary, which is currently 

the principal discharge for the Ganges, Brahmaputra, and Meghna River drainage basins, and 35 

km south of the Padma River (Ganges). The borehole site is located on the Ganges floodplain near 

the Gopalganj beel (a shallow ephemeral lake characterized by carbonaceous sediment) (Brammer, 

1996). Much of the sediment transported by the rivers and deposited in the basin originates in 

crystalline rocks of the high Himalayas, with lesser additions from the Indian Shield to the west, the 

Shillong Plateau to the north, and Tertiary-age sedimentary rocks that are exposed in the foothills to 

the Himalayas. The Tertiary rock is composed mostly of sediment originally shed from the 

ancestral Indian Shield and early Himalaya uplift, which was buried along the paleo-Indian 

continental margin, lithified, and tectonically uplifted into the weathering zone during the IndiaAsia collision. Holocene sediment accumulation rates for the Bengal delta range up to 1 cm per 

year as a result of the large amount of sediment transport, sea level rise, and accommodation space 

created by subsidence (Goodbred and Kuehl, 2000). 

Methods 

Sample Collection 

Sediment samples were collected from a borehole by coring selected depth intervals during the 

spring and summer of 2004. The borehole was drilled by the Geological Survey of Bangladesh 

(GSB); borehole SH-2 was located at 23.205483° N latitude and 90.069361° E longitude (WGS84 

datum) and was drilled to a total depth of 450 meters. Drilling fluid used by the GSB was a mix of 

water and bentonite with the addition of barite when drilling advanced below approximately 230 m 

depth. Thirty-seven samples of sediment were collected from the 450 m borehole at approximately 

10 m intervals. Recovered sediment was described in the field (Appendix 1). Bulk samples were 

air-dried prior to analysis and are designated as –AD in the appendices. 

Aliquots of each sample were placed in glass vials filled with argon gas at the drill site to preserve 

the oxidation state of iron and arsenic. These preserved samples are identified as – P in subsequent 

tables. Some preserved samples were collected at slightly different depth intervals than the –AD 

samples, as listed in Appendix 2. Preserved samples were collected using a detipped 10 mL 

syringe that was used to extract the sediment recovered in the lowest section of the core barrel 

(immediately above the coring bit). This material was considered to be the least contaminated by 

2
drilling fluid. The sediment collected in the detipped syringe was then transferred to an amber 

glass vial equipped with a Teflon-coated septum. Sediment was transferred into the vial while the 

vial was purged with flowing argon gas. The vial was capped and flushed with additional argon for 

five minutes using needles to introduce and vent the gas through the septum. After purging with 

the gas, the vial was frozen until shipment to the United States. During shipment the vials thawed 

but remained sealed; they were promptly refrozen upon arrival at the USGS laboratories. 

Figure 1. Map showing the location of the Rajoir study site in south-central Bangladesh. 

Grain-size Analysis 

Aliquots of the bulk sediment samples were analyzed to determine grain size using a Malvern 

Mastersizer S long bed laser refraction instrument. Approximately 3 gram splits of sediment were 

soaked overnight in 40 mL of distilled water amended with 20 mL of 0.25 weight percent sodium 

hexametaphosphate to enhance particle disaggregation and dispersion. Consistent with the 

observed lack of cementation, Rajoir sediment samples dispersed easily. Grain-size characteristics 

of the samples are presented in Appendix 3. 

Mineralogy 

To determine the major mineral phases in the sediment, splits of 37 bulk samples were ground to < 

50 μm (micrometer) in an agate shatterbox prior to analysis by X-ray diffraction. Side-packed 

3
mounts were prepared by loading the powdered sample against frosted glass to minimize 

preferential orientation. The mounts were analyzed using Ni-filtered, Cu Kα radiation on a 

Siemens D500 equipped with a graphite monochromater. Samples were scanned from 4 to 64 

degrees 2θ with a 0.02 degree step size and count time of 2 seconds per step. 

Ten samples were prepared according to the methods described in Eberl (2002) for quantitative 

mineral analysis. This method requires micronizing the sample with ZnO as an internal standard. 

The ROCKJOCK (Eberl, 2002) program was then used to calculate the abundance of major mineral 

constituents. Analytical precision of the ROCKJOCK method is estimated to be within ten relative 

percent. Results of the qualitative and quantitative XRD analyses are listed in Appendices 4 and 5. 

Bulk Chemical Analyses 

Air-dried samples were analyzed to determine chemical composition by Combustion; Inductively 

Coupled Plasma Atomic Emission Spectroscopy (ICP-AES); Energy Dispersive X-ray 

Fluorescence (EDXRF); and Hydride Generation Atomic Absorption Spectrophotometery 

(HGAAS). All samples were homogenized using a mortar and pestle, then split and ground in an 

agate shatterbox prior to analysis. The combustion procedure of Brown and Curry (2002a, 2002b) 

determined the total carbon and sulfur concentrations. Carbonate carbon was measured by 

evolution of carbon dioxide using the Chittick method (Dreimanis, 1962). Samples analyzed by 

ICP-AES were first dissolved using the four acid digestion as described in Briggs (2002). ICPAES determined the concentration of 40 elements. EDXRF analyses followed the procedure of 

Siems (2002) in which a pressed powder mount was analyzed directly for 30 elements. Arsenic 

concentrations were also obtained using HGAAS according to the method of Hageman and others 

(2002). HGAAS was used as an additional technique to measure arsenic content because of its 

lower detection limit, and higher precision and accuracy. Results of the chemical analyses of the 

bulk samples are listed in Appendices 6 though 9. 

Precision of duplicate splits of the same sample were within 10 relative percent for elements with 

concentrations greater than 3 times the detection limit for Combustion, Chittick, ICP-AES, and 

EDXRF methods. Elements present in lower concentrations were reproduced within 30 relative 

percent. Duplicate total arsenic measurements by HGAAS were consistently within 4 relative 

percent. Analyses of solid and rock standards submitted with the samples yielded results within the 

precision and accuracy described in Taggart (2002). 

Chemical Extraction Analyses 

Selected sediment samples were treated with 0.5 N HCl primarily to determine the oxidation state 

and abundance of acid-soluble iron. A 3 to 5 gram aliquot of each of the 37 frozen, preserved 

sediment samples was transferred to an acid-washed amber serum vial under flowing high-purity 

nitrogen. The sediment was exposed to air for a few minutes during the transfer, but experiments 

determined that a minimum of 30 minutes of exposure of the cold sediment was needed before iron 

oxidation was detectable in the extract solutions. Forty mL of 0.5 N hydrochloric acid was added; 

the vial was sealed with a rubber septum, purged with nitrogen gas, wrapped with aluminum foil, 

and shaken periodically. Following 24 hours, 30 mL of the acid solution was withdrawn through 

the septum and filtered through a 0.2 μm syringe filter. An aliquot of the solution was immediately 

analyzed to determine the concentration of dissolved ferrous iron and dissolved total iron using the 

Orthophenanthroline method (Clesceri and others, 1998) (Appendix 10). A second aliquot of the 

remaining solution was analyzed by ICP-AES for 25 elements and for arsenic by HGAAS. Results 

4
of the analyses are presented in Appendices 10 and 11. Measured concentrations of extractions 

with 0.5 N HCl of replicate samples of the sediment typically reproduced within 15 percent, but 

ratios of ferrous to total extractable iron were reproduced within 3 percent. Variations in element 

concentrations in the replicates are attributed to sample heterogeneity. 

The abundances of acid-volatile sulfide (AVS), acid-soluble sulfate, and reducible sulfide (DI), 

which is mainly pyritic sulfur, were determined following the extraction scheme of Tuttle and 

others (1986). Sulfur speciation was determined on a 2 to 5 gram aliquot of preserved sediment 

that was transferred while only partially thawed into the reaction vessel. Under flowing nitrogen, 

the sample was combined with 80 mL of 6 N HCl that contained 2 grams of stannous chloride 

(SnCl2). The SnCl2 was added to reduce ferric iron in the samples that might oxidize evolved 

hydrogen sulfide (H2S) in the reaction vessel (Rice and others, 1993). After 15 to 30 minutes, the 

reaction vessel was heated to boiling to increase the reaction rate. The evolved H2S was carried in 

flowing nitrogen through a reservoir of buffer solution (pH 4) to remove HCl and bubbled through 

a trap containing 1 N silver nitrate (AgNO3) until the reaction was complete. The resulting silver 

sulfide (Ag2S) was collected by filtration, air-dried, and weighed to measure the abundance of 

AVS. The acid solution was separated from the residual solid by filtration, and the residual solid 

was air-dried and weighed. The acid solution was reacted with 10 mL of 10% barium chloride to 

precipitate dissolved sulfate as barium sulfate, which is considered acid-soluble sulfate. The 

residual sediment from the AVS extraction was placed in a reaction vessel under flowing nitrogen 

and combined with 50 mL of 1M chromous chloride (CrCl2) in 4 N HCl containing 10 milliliters of 

ethanol. Chromium (II) converts reducible sulfide minerals (i.e., pyrite) to H2

S. The H2S is 

transferred to a 1N AgNO3 trap as described for the AVS extraction. The solution is boiled for 

approximately 1 hour or until evolution of H2S has stopped. Results of the sulfur speciation are 

listed in Appendix 12. 

Results 

Physical and mineralogical characteristics 

Sediment samples from the Rajoir borehole are typically gray and range from silty clay to pebbly 

sand. The relative grain size distribution of the sample materials from the borehole are plotted in 

Figure 2. XRD analyses identified quartz as the major constituent of the sediment with minor 

amounts of plagioclase, potassium feldspar, mica, chlorite, and amphiboles (Appendices 4 and 5). 

Confirmed authigenic phases detected by XRD in a few samples include siderite and pyrite; calcite 

was not detected in any of the samples. 

5
Figure 2. Ternary diagram of results of grain size analyses (Appendix 3) in sediment samples 

recovered from the borehole at Rajoir, Bangladesh. 

Bulk Chemical Composition 

The median, minimum, and maximum concentrations of chemical constituents measured in bulk 

air-dried sediment from the SH-2 borehole are listed in Table 1. Compared to the sediment 

analyzed from the Srirampur borehole located approximately 70 km east of the current study site 

(Breit and others, 2006), Rajoir sediment has lower contents of arsenic, organic carbon, and sulfur. 

Total arsenic concentrations of the Rajoir sediment range from 0.6 to 21 ppm based on the HGAAS 

analyses. 

Unusually high concentrations of barium (>500 ppm) were detected in sediment collected below 

depths of approximately 230 meters. The drilling engineer reported that 230 m was the depth at 

which barite was added to the drilling fluid to prevent potential blowouts. Because sulfur is an 

important component of the processes active within the sediment, the following procedure was used 

to correct sulfur concentrations based on the excess barium content. 

Potassium and barium have a recognized geochemical association in potassium feldspars and micas 

(Puchelt, 1978), which are the most common residence of barium in sediments. This association is 

evident in the sediment collected at Rajoir and elsewhere in Bangladesh (Breit and others, 2006). 

Samples recovered from depths less than 230 meters (uncontaminated with barite) have a strong 

correlation of barium with potassium (r2

 = 0.9; fig. 3). The amount of excess barium in the deeper 

6
samples was then calculated based on the amount of barium expected for the measured amount of 

potassium (equation 1). Because of the uncertainty in the analytical data and the deviation from an 

ideal relation between Ba and K, only samples with greater than 200 ppm excess barium were 

considered to have sufficient contamination to merit correction. In addition, barium contents of 

200 ppm, if contained in barite, would correspond to approximately 0.005 weight percent sulfur, 

which is close to the detection limit for sulfur analyses. Accordingly, sulfur concentrations in the 

samples were corrected using equation 2. Results of the recalculation of sulfur concentration are 

plotted in Figure 4. Note that the high sulfur concentrations detected in the samples are unaffected 

by the barite correction. 

Ba (ppm) excess = Ba (ppm) measured – (170* K (wt. %) + 60) (1) 

Sulfur (wt.%) corrected = Sulfur (wt.%) measured – (0.233 * Ba (wt.%) excess) (2) 

Figure 3. Plot of potassium vs. barium content of the Rajoir borehole sediment. Regression line was 

calculated using samples from depths less than 230 m (r = 0.9), which are unaffected by barite in 

the drilling mud. Scatter above the line is attributed to barite contamination. 

2

7
Figure 4. Depth profile comparing bulk sulfur concentration of the sediment from the Rajoir 

borehole with concentrations corrected for barite contamination. Only five of the 37 samples 

required significant correction. (wt.%, weight percent). 

8
Table 1. Median, minimum and maximum concentrations of chemical constituents of sediment 

recovered from the SH-2 borehole in Rajoir, Bangladesh. 

[ wt.%, weight percent; ppm, parts per million; ICP-AES, Inductively Coupled Plasma Atomic Emission Spectroscopy; 

EDXRF, Energy Dispersive X-ray Fluorescence Spectrometry; HGAAS, Hydride Generation Atomic Absorption 

Spectrophotometry; *, sulfur concentrations are values corrected for barite contamination; detection ratio is the number 

of analyses above the detection limit/total number of analyses; nr, not reported] 

Element 

(units) 

Analytical 

Method 

Median Minimum Maximum Detection 

Ratio 

Al (wt.%) ICP-AES 4.9 3.2 11 37/37 

Ca (wt.%) ICP-AES 0.83 0.4 1.5 37/37 

Fe (wt.%) ICP-AES 2.1 0.79 6.5 37/37 

K (wt.%) ICP-AES 1.8 1.2 3.0 37/37 

Mg (wt.%) ICP-AES 0.47 0.19 1.6 37/37 

Na (wt.%) ICP-AES 1.1 0.22 1.4 37/37 

P (wt.%) ICP-AES 0.025 0.009 0.061 37/37 

Ti (wt.%) ICP-AES 0.24 0.098 0.48 37/37 

C-total (wt.%) Combustion 0.11 <0.04 1.1 34/37 

C-carbonate 

(wt.%) 

Chittick 0.05 0.01 0.42 37/37 

S (wt.%)* Combustion 0.01 <0.005 0.17 36/37 

Ag (ppm) ICP-AES <2 <2 <2 0/37 

Ag (ppm) EDXRF <1 <1 <1 0/37 

As (ppm) ICP-AES <10 <10 25 2/37 

As (ppm) EDXRF <2 <2 21 10/37 

As (ppm) HGAAS 1.2 0.6 21 37/37 

Au (ppm) ICP-AES <8 <8 <8 0/37 

Ba (ppm) ICP-AES 400 220 1100 37/37 

Ba (ppm) EDXRF 440 250 1200 37/37 

Be (ppm) ICP-AES 2.1 1.3 4.2 37/37 

Bi (ppm) ICP-AES <10 <10 <10 37/37 

Bi (ppm) EDXRF <5 <5 <5 0/37 

Br (ppm) EDXRF <1 <1 6 33/37 

Cd (ppm) ICP-AES <2 <2 <2 37/37 

Cd (ppm) EDXRF <1 <1 <1 0/37 

Ce (ppm) ICP-AES 67 29 110 37/37 

Ce (ppm) EDXRF 71 29 130 37/37 

Co (ppm) ICP-AES 7.9 2.4 48 37/37 

Cr (ppm) ICP-AES 36 12 110 37/37 

Cr (ppm) EDXRF 36 17 120 37/37 

Cs (ppm) EDXRF 8 <5 18 32/37 

Cu (ppm) ICP-AES 6.6 2.1 76 37/37 

Cu (ppm) EDXRF nr nr nr nr 

Eu (ppm) ICP-AES <2 <2 2 1/37 

Ga (ppm) ICP-AES 9.6 <4 30 33/37 

Ga (ppm) EDXRF 11 6 24 37/37 

Ge (ppm) EDXRF <2 <2 4 1/37 

Ho (ppm) ICP-AES <4 <4 <4 0/37 

La (ppm) ICP-AES 33 14 58 37/37 

La (ppm) EDXRF 39 15 66 37/37 

9
Table 1. Median, minimum and maximum of chemical constituents—Continued. 

Element 

(units) 

Analytical 

Method 

Median Minimum Maximum Detection 

Ratio 

Li (ppm) ICP-AES 16 9.6 67 37/37 

Mn (ppm) ICP-AES 470 110 2800 37/37 

Mo (ppm) ICP-AES <2 <2 3.4 3/37 

Mo (ppm) EDXRF <2 <2 2 2/37 

Nb (ppm) ICP-AES 10 <4 19 32/37 

Nb (ppm) EDXRF 9 5 19 37/37 

Nd (ppm) ICP-AES 30 12 44 37/37 

Nd (ppm) EDXRF 32 <10 48 36/37 

Ni (ppm) ICP-AES 17 8.5 60 37/37 

Ni (ppm) EDXRF nr nr nr nr 

Pb (ppm) ICP-AES 19 9.4 39 37/37 

Pb (ppm) EDXRF 18 13 37 37/37 

Rb (ppm) EDXRF 100 65 210 37/37 

Sb (ppm) EDXRF <2 <2 <2 0/37 

Sc (ppm) ICP-AES 7.6 3.2 18 37/37 

Se (ppm) EDXRF <1 <1 <1 0/37 

Sn (ppm) ICP-AES <5 <5 30 6/37 

Sn (ppm) EDXRF 3 <2 6 32/37 

Sr (ppm) ICP-AES 130 51 160 37/37 

Sr (ppm) EDXRF 140 54 170 37/37 

Ta (ppm) ICP-AES <20 <20 <20 37/37 

Th (ppm) ICP-AES nr nr nr nr 

Th (ppm) EDXRF 11 5 24 37/37 

U (ppm) ICP-AES <100 <100 <100 0/37 

U (ppm) EDXRF <4 <4 7 12/37 

V (ppm) ICP-AES 50 22 140 37/37 

V (ppm) EDXRF 51 24 140 37/37 

W (ppm) EDXRF <5 <5 160 1/37 

Y (ppm) ICP-AES 16 7.6 29 37/37 

Y (ppm) EDXRF 22 12 37 37/37 

Yb (ppm) ICP-AES 1.8 <1 3.6 34/37 

Zn (ppm) ICP-AES 39 24 120 37/37 

Zn (ppm) EDXRF 46 30 110 37/37 

Zr (ppm) EDXRF 130 98 290 37/37 

Chemical Extractions 

Analyses of the 0.5 N HCl extraction solutions verified that the sediment is chemically reduced 

with respect to iron. Fe2+/Fetotal values are typically greater than 0.9 (Appendix 10). As much as 1 

wt.% iron was dissolved from the Rajoir sediment, which is tentatively attributed to dissolution of 

siderite. Substantial amounts of aluminum, calcium, magnesium, manganese, potassium, sodium, 

and silicon were also dissolved by 0.5 N HCl (Appendix 11). These elements are attributed to 

dissolution of detrital silicates and siderite. Reaction of the acid with portions of feldspars, micas, 

and other detritus weathered during transport and shallow burial likely accounts for Al, Si, K, Na, 

and some of the Ca, Mg, and Mn. Dissolution of siderite likely released Ca, Mg, and Mn, as well 

as iron, based on preliminary analyses of siderite grains using a scanning electron microscope 

equipped with energy dispersive spectroscopy. 

10
Wilkin and Ford (2002) noted loss of dissolved arsenic in sulfidic sediment treated with HCl 

solutions that were intended to evaluate the abundance of labile arsenic. They attributed the arsenic 

loss to precipitation of amorphous orpiment (As2S3) by reaction of dissolved arsenic and H2S 

evolved by reaction of the AVS with HCl. Therefore, the arsenic concentrations of the 0.5 N HCl 

extract solutions in this study should be viewed with caution. The potential of orpiment 

precipitation in the 0.5 N HCl extraction was evaluated using Geochemist’s Workbench with the 

LLNL V8 R6 combined database, which was modified with the thermodynamic data of Nordstrom 

and Archer (2003) and Pokrovski and others (2002). Results of AVS extraction (Appendix 12) and 

the abundance of arsenic and iron in the 0.5 N HCl solutions (Appendix 11) were used to evaluate 

the degree of saturation of amorphous orpiment. The amount of AVS extracted by the 0.5 N HCl is 

likely to be smaller than the AVS extracted by hot 6 N HCl, so the calculations are considered to 

indicate the maximum saturation values. One of the 8 samples analyzed for sulfur speciation was 

oversaturated with respect to amorphous orpiment. Samples selected for sulfur speciation generally 

contain greater contents of sulfur than most of the sediment samples; therefore, the remaining 

samples are unlikely to produce HCl extract solutions saturated with amorphous orpiment. This 

evaluation does not eliminate the concern for orpiment precipitation in the Rajoir sediment, but the 

problem is likely to be less significant than in the sediment evaluated by Wilkin and Ford (2002). 

Sulfur speciation extractions detected AVS, acid-soluble sulfate, and reducible sulfur (DI) in the 

borehole sediment (Appendix 12). Concentrations of AVS ranged from 10 to 5250 ppm, acidsoluble sulfate measured 30 to 130 ppm, and DI was typically the most abundant form of sulfur, 30 

to 9580 ppm. Reducible sulfide (DI) is attributed to pyrite. For several samples, the total amount 

of sulfur extracted is substantially different than the total sulfur concentrations measured for the 

bulk, air-dried sediment. The speciation scheme was evaluated with synthetic standards and 

determined to be reliable; therefore, the contrasting values are attributed to sample heterogeneity. 

References Cited 

Brammer, Hugh, 1996, The geography of the soils of Bangladesh: Dhaka, Bangladesh, The 

University Press Limited, 287 p. 

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13
Appendix 1. Depth interval and description of air-dried sediment samples from the SH-2 borehole, 

Rajoir, Bangladesh. 

Sample Depth Description 

(meters) 

SH-2/1-AD 11.0-11.1 light greenish-gray (10Y 7/1), silty clay 

SH-2/2-AD 21.6-21.9 greenish-gray (5GY 6/1), fine sand 

SH-2/3-AD 35.5-35.7 greenish-gray (10GY 6/1), fine sandy silt 

SH-2/4-AD 47.9-48.2 greenish gray (5GY 5/1), fine sand 

SH-2/5-AD 60.5-60.8 light greenish-gray (5GY 7/1), fine sand 

SH-2/6-AD 72.5-72.8 greenish-gray (10GY 6/1), fine sand 

SH-2/7-AD 86.3-86.6 greenish-gray (5GY 5/1), fine sand 

SH-2/8-AD 98.5-98.9 greenish gray (5GY 5/1), clayey medium sand 

SH-2/9-AD 98.9-99.1 light greenish gray (10GY 7/1), clay 

SH-2/10-AD 110.6-110.9 dark greenish gray (10Y 4/1) pebbly medium sand 

SH-2/11-AD 122.2-123.1 light greenish gray (5BG 8/1), medium sand 

SH-2/12-AD 135.2-135.9 greenish gray, (5GY 5/1), fine sand 

SH-2/13-AD 147.8-148.7 light greenish gray (5GY 7/1), fine sand 

SH-2/14-AD 158.5-159.4 greenish gray (10Y 6/1), fine sand 

SH-2/15-AD 167.0-167.6 light greenish gray, (5GY 7/1), clayey fine sand 

SH-2/16-AD 178.9-179.8 light gray, (2.5Y 7/2), silty fine sand 

SH-2/17-AD 192.3-193.2 light gray (5Y 7/2), pebbly medium sand 

SH-2/18-AD 204.2-205.1 light greenish gray (5BG 7/1), fine sand 

SH-2/19-AD 217.3-217.8 light greenish gray (10Y 7/1), medium sand 

SH-2/20-AD 229.5-230.4 light greenish gray (5GY 7/1), medium sand 

SH-2/21-AD 240.8-241.7 greenish gray (10Y 6/1), pebbly medium sand 

SH-2/22-AD 253.0-253.9 greenish gray (10Y 6/1), pebbly medium sand 

SH-2/23-AD 265.2-266.1 light greenish gray (5GY 7/1) clayey fine sand 

SH-2/24-AD 277.4-278.0 greenish gray (5BG 6/1), clayey medium sand 

SH-2/25-AD 289.6-290.3 light greenish gray (10BG 7/1) fine sand 

SH-2/26-AD 301.8-302.7 light greenish gray (5BG 7/1), medium sand 

SH-2/27-AD 316.8-317.0 light bluish gray (5B 7/1), fine sandy clay 

SH-2/28-AD 329.8-330.1 light greenish gray (10GY 7/1), medium sand 

SH-2/29-AD 342.6-343.2 very pale brown (10YR 7/3), fine sand 

SH-2/30-AD 353.6-354.5 light brownish gray (10YR 6/2), medium sand 

SH-2/31-AD 365.8-366.7 pale brown (10YR 6/3) medium sand 

SH-2/32-AD 378.6-378.9 mottled light gray (10YR7/1) and brown-yellow (10YR 6/6) clay 

SH-2/33-AD 390.1-391.1 light greenish gray (10GY 7/1) fine sandy, silty clay 

SH-2/34-AD 403.3-404.2 light greenish gray (10GY 7/1) fine sandy clay 

SH-2/35-AD 416.4-417.3 greenish gray (5GY 6/1) fine sand 

SH-2/36-AD 429.8-430.7 very pale brown (10YR 7/3), fine sand 

SH-2/37-AD 449.6-450.5 greenish gray (5GY 6/1) fine sandy clay 

14
Appendix 2. Depth of sediment samples that were preserved in glass vials, flushed with argon, and 

frozen after collection from the SH-2 borehole, Rajoir, Bangladesh.

Sample Depth 

(meters) 

SH-2/1-P 11.6 

SH-2/2-P 21.9 

SH-2/3-P 35.7 

SH-2/4-P 48.2 

SH-2/5-P 60.8 

SH-2/6-P 72.8 

SH-2/7-P 86.6 

SH-2/8-P 98.9 

SH-2/9-P 99.1 

SH-2/10-P 110.9 

SH-2/11-P 123.1 

SH-2/12-P 135.9 

SH-2/13-P 148.7 

SH-2/14-P 159.4 

SH-2/15-P 167.6 

SH-2/16-P 179.8 

SH-2/17-P 193.2 

SH-2/18-P 205.1 

SH-2/19-P 217.8 

SH-2/20-P 230.4 

SH-2/21-P 241.7 

SH-2/22-P 253.9 

SH-2/23-P 266.1 

SH-2/24-P 278.0 

SH-2/25-P 290.3 

SH-2/26-P 302.7 

SH-2/27-P 317.0 

SH-2/28-P 330.1 

SH-2/29-P 343.2 

SH-2/30-P 354.5 

SH-2/31-P 366.7 

SH-2/32-P 378.9 

SH-2/33-P 391.1 

SH-2/34-P 404.2 

SH-2/35-P 417.3 

SH-2/36-P 430.7 

SH-2/37-P 450.5 

15
Appendix 3. Results of grain size analysis of air-dried sediment samples collected from the SH-2 

borehole, Rajoir village, Bangladesh. Designations as sand, silt, and clay follow the size definitions 

of Wentworth (1922). 

[Eric Fisher, Analyst; wt.%, weight percent] 

Sample Sand Silt Clay Description 

(wt.%) (wt.%) (wt.%) 

SH-2/1-AD 6.5 80.0 13.6 silt 

SH-2/2-AD 69.8 27.7 2.4 silty sand 

SH-2/3-AD 27.6 62.1 10.3 sandy silt 

SH-2/4-AD 89.3 9.1 1.6 sand 

SH-2/5-AD 87.4 10.9 1.7 sand 

SH-2/6-AD 81.7 16.0 2.3 sand 

SH-2/7-AD 89.2 8.5 2.4 sand 

SH-2/8-AD 92.3 6.1 1.6 sand 

SH-2/9-AD 20.9 57.8 21.3 sandy silt 

SH-2/10-AD 73.1 23.7 3.2 silty sand 

SH-2/11-AD 86.9 11.1 1.9 sand 

SH-2/12-AD 87.6 11.4 1.0 sand 

SH-2/13-AD 94.9 4.5 0.6 sand 

SH-2/14-AD 90.6 8.2 1.2 sand 

SH-2/15-AD 79.9 17.3 2.9 sand 

SH-2/16-AD 93.5 5.2 1.3 sand 

SH-2/17-AD 89.7 8.5 1.8 sand 

SH-2/18-AD 94.8 4.5 0.7 sand 

SH-2/19-AD 94.6 4.5 0.9 sand 

SH-2/20-AD 96.5 3.0 0.5 sand 

SH-2/21-AD 90.6 8.2 1.3 sand 

SH-2/22-AD 95.0 4.5 0.5 sand 

SH-2/23-AD 85.0 12.6 2.4 sand 

SH-2/24-AD 94.2 5.2 0.6 sand 

SH-2/25-AD 91.1 8.0 0.9 sand 

SH-2/26-AD 98.2 1.4 0.4 sand 

SH-2/27-AD 79.2 17.4 3.4 sand 

SH-2/28-AD 96.7 2.8 0.5 sand 

SH-2/29-AD 92.9 6.2 1.0 sand 

SH-2/30-AD 94.2 4.9 1.0 sand 

SH-2/31-AD 90.9 7.2 1.9 sand 

SH-2/32-AD 1.6 45.4 53.0 silty clay 

SH-2/33-AD 22.3 57.0 20.7 sandy silt 

SH-2/34-AD 17.1 66.3 16.6 sandy silt 

SH-2/35-AD 94.7 4.3 1.0 sand 

SH-2/36-AD 94.7 4.2 1.1 sand 

SH-2/37-AD 23.6 66.8 9.6 sandy silt 

16
17

Appendix 4. Major and minor minerals detected by X-ray diffraction analysis of air-dried sediment 

samples from the SH-2 borehole, Rajoir, Bangladesh. 

 [XX, major constituent; X, minor constituent; TI, tentative identification as minor phase; <, not detected; Plag., 

plagioclase; K-spar, potassium feldspar; Amph., amphibole] 

Sample Quartz Plag. K-spar Mica Chlorite Amph. Siderite 

SH-2/1-AD XX X X X TI TI < 

SH-2/2-AD XX X X X TI X < 

SH-2/3-AD XX X X X TI X < 

SH-2/4-AD XX X X < TI X < 

SH-2/5-AD XX X X X TI X < 

SH-2/6-AD XX X X X TI X < 

SH-2/7-AD XX X X X TI X < 

SH-2/8-AD XX X X X TI TI < 

SH-2/9-AD XX X TI X TI TI < 

SH-2/10-AD XX X TI X < TI TI 

SH-2/11-AD XX X TI X TI TI < 

SH-2/12-AD XX X X X TI < TI 

SH-2/13-AD XX X X X TI TI < 

SH-2/14-AD XX X TI X < TI < 

SH-2/15-AD XX X X X TI < < 

SH-2/16-AD XX X X TI < < < 

SH-2/17-AD XX X X X TI TI < 

SH-2/18-AD XX X X X TI X < 

SH-2/19-AD XX X X X TI TI TI 

SH-2/20-AD XX X X X X X < 

SH-2/21-AD XX X X X TI TI < 

SH-2/22-AD XX X X X TI X TI 

SH-2/23-AD XX X X X TI TI X 

SH-2/24-AD XX X X X TI TI < 

SH-2/25-AD XX X X X TI TI TI 

SH-2/26-AD XX X X X TI X X 

SH-2/27-AD XX X X X < TI < 

SH-2/28-AD XX X X X TI TI X 

SH-2/29-AD XX X X X TI X < 

SH-2/30-AD XX X X X < TI < 

SH-2/31-AD XX X X X TI X < 

SH-2/32-AD XX X X X X TI < 

SH-2/33-AD XX X X X < < X 

SH-2/34-AD XX X X X < TI < 

SH-2/35-AD XX X X X TI X < 

SH-2/36-AD XX X X X TI TI < 

SH-2/37-AD XX X X X TI < < 
18

 Qu ag. ph. ca e 

Appendix 5. Results of quantitative mineralogical analysis by X-ray diffraction of air-dried sediment samples from 

SH-2 borehole at Rajoir, Bangladesh. Abundances determined using the ROCKJOCK procedure of Eberl (2002). 

 [K-spar, potassium feldspars; Plag., plagioclase; Amph., amphibole; Mica, sum of muscovite, phlogopite and biotite; wt.%, weight per

Sample artz K-spar Pl Am Mi Chlorite Smectit Kaolin

 (wt.%) 

AD 34 

(wt.%) (wt.%) (wt.%) 

8 13 2 30 9 <1 2 

(wt.%) (wt.%) (wt.%) (wt.%

SH-2/1-

SH-2/2-AD 45 12 17 4 13 7 2 <1 

14 16 3 6 4 1 <1 

14 13 1 22 5 7 2 14 9 1 9 3 7 1 

15 16 3 7 5 3 1 14 14 2 8 5 4 1 13 13 2 6 5 4 <1 

8 <1 <1 27 5 20 8 

14 14 2 6 2 3 <1 

SH-2/7-AD 57 SH-2/12-AD 34 SH-2/15-AD 54 SH-2/18-AD 50 SH-2/24-AD 52 SH-2/28-AD 57 SH-2/32-AD 22 SH-2/36-AD 59 
19

Appendix 6. Results of carbon and sulfur analyses of air-dried sediment samples from the SH-2 

borehole, Rajoir, Bangladesh. Sulfur and total carbon determined by Combustion (Brown and Curry, 

2002a; 2002b). Carbonate carbon determined using the Chittick method (Dreimanis, 1962). Sulfur 

was corrected (Sulfur (corr)) for barite contamination as described in the text. 

[wt.%, weight percent] 

Sample Sulfur Sulfur (corr) Total Carbon Carbonate Carbon 

 (wt.%) (wt.%) (wt.%) (wt.%) 

SH-1/1-AD 0.080 0.080 0.33 0.05 

SH-1/2-AD 0.070 0.070 0.29 0.30 

SH-1/3-AD 0.033 0.033 0.60 0.22 

SH-1/4-AD 0.010 0.010 0.11 0.07 

SH-1/5-AD 0.004 0.004 0.09 0.05 

SH-1/6-AD 0.005 0.005 0.11 0.04 

SH-1/7-AD 0.009 0.009 0.05 0.04 

SH-1/8-AD 0.009 0.009 0.15 0.15 

SH-1/9-AD 0.079 0.079 1.1 0.20 

SH-1/10-AD 0.004 0.004 0.41 0.14 

SH-1/11-AD 0.005 0.005 0.09 0.04 

SH-1/12-AD 0.011 0.011 0.21 0.09 

SH-1/13-AD 0.007 0.007 0.10 0.07 

SH-1/14-AD 0.006 0.006 0.11 0.08 

SH-1/15-AD 0.082 0.082 0.46 0.12 

SH-1/16-AD 0.012 0.012 0.04 0.04 

SH-1/17-AD 0.010 0.010 0.05 0.02 

SH-1/18-AD 0.010 0.010 0.07 0.07 

SH-1/19-AD 0.006 0.006 0.20 0.07 

SH-1/20-AD 0.065 0.065 0.06 0.03 

SH-1/21-AD 0.002 0.002 <0.04 0.03 

SH-1/22-AD 0.013 0.013 0.10 0.04 

SH-1/23-AD 0.031 0.031 0.30 0.06 

SH-1/24-AD 0.013 0.013 0.11 0.04 

SH-1/25-AD 0.014 0.014 0.13 0.07 

SH-1/26-AD 0.007 0.007 0.41 0.03 

SH-1/27-AD 0.009 0.005 <0.04 0.04 

SH-1/28-AD 0.008 0.008 0.20 0.11 

SH-1/29-AD 0.022 0.004 0.06 0.05 

SH-1/30-AD 0.020 0.003 <0.04 0.04 

SH-1/31-AD 0.024 0.012 0.06 0.04 

SH-1/32-AD <0.002 <0.002 0.10 0.05 

SH-1/33-AD 0.032 0.032 0.59 0.42 

SH-1/34-AD 0.173 0.173 0.10 0.04 

SH-1/35-AD 0.004 0.004 <0.04 0.04 

SH-1/36-AD 0.029 0.024 0.05 0.03 

SH-1/37-AD 0.068 0.068 0.22 0.09 
Appendix 7. Results of Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) analyses of air-drie

SH-2 borehole, Rajoir, Bangladesh. [Paul Briggs, USGS, Analyst; wt.% weight percent; ppm, parts per million; nr, not reported] 

Sample Al Ca Fe K Mg Na P Ti Ag As Au Ba 

wt. % wt. % wt. % wt. % wt. % wt. % wt. % wt. % ppm ppm ppm ppm 

SH-2/1-AD 8.7 0.87 4.0 2.9 1.5 1.1 0.050 0.45 <2 <10 <8 570 

SH-2/2-AD 5.8 1.5 2.9 2.0 1.1 1.3 0.060 0.33 <2 <10 <8 400 SH-2/3-AD 8.0 1.3 4.2 2.6 1.6 1.2 0.061 0.44 <2 <10 <8 500 SH-2/4-AD 5.7 1.4 2.5 2.0 0.8 1.4 0.036 0.28 <2 <10 <8 390 SH-2/5-AD 5.5 1.4 2.3 1.8 0.69 1.4 0.038 0.28 <2 <10 <8 370 SH-2/6-AD 5.4 1.2 2.1 1.9 0.67 1.4 0.028 0.22 <2 <10 <8 380 SH-2/7-AD 4.6 1.0 1.6 1.6 0.47 1.3 0.023 0.14 <2 <10 <8 330 SH-2/8-AD 3.6 0.51 1.9 1.4 0.4 0.77 0.021 0.12 <2 <10 <8 280 SH-2/9-AD 9.0 1.0 4.7 2.6 1.5 1.1 0.053 0.41 <2 15 <8 550 

SH-2/10-AD 3.2 0.72 2.7 1.2 0.42 0.74 0.024 0.10 <2 <10 <8 220 SH-2/11-AD 4.9 1.0 1.5 1.8 0.44 1.3 0.023 0.16 <2 <10 <8 350 SH-2/12-AD 7.5 0.59 4.2 3.0 1.1 1.2 0.019 0.41 <2 <10 <8 500 SH-2/13-AD 4.8 0.89 1.8 1.7 0.42 1.1 0.027 0.25 <2 <10 <8 350 SH-2/14-AD 5.4 0.87 2.1 2.0 0.52 1.2 0.028 0.25 <2 <10 <8 390 SH-2/15-AD 4.9 0.55 3.1 1.7 0.46 0.75 0.023 0.28 <2 <10 <8 370 SH-2/16-AD 3.9 0.49 0.79 1.8 0.19 0.87 0.009 0.11 <2 <10 <8 380 SH-2/17-AD 5.4 0.86 1.5 2.0 0.44 1.3 0.024 0.21 <2 <10 <8 390 SH-2/18-AD 5.2 1.0 1.9 1.7 0.49 1.2 0.028 0.25 <2 <10 <8 380 SH-2/19-AD 4.9 0.78 2.0 1.8 0.48 1.1 0.023 0.21 <2 <10 <8 380 SH-2/20-AD 4.9 0.79 1.3 1.8 0.35 1.2 0.019 0.16 <2 <10 <8 380 SH-2/21-AD 4.5 0.77 1.5 1.7 0.36 1.1 0.023 0.18 <2 <10 <8 430 SH-2/22-AD 4.9 0.68 1.5 1.8 0.37 1.1 0.020 0.18 <2 <10 <8 520 SH-2/23-AD 5.2 0.61 2.3 2.0 0.45 1.1 0.021 0.18 <2 <10 <8 480 SH-2/24-AD 5.4 0.81 1.9 1.9 0.6 1.1 0.025 0.25 <2 <10 <8 530 SH-2/25-AD 5.4 0.86 2.1 1.8 0.54 1.2 0.034 0.25 <2 <10 <8 380 SH-2/26-AD 4.6 0.53 2.6 2.0 0.36 1.1 0.022 0.14 <2 <10 <8 400 SH-2/27-AD 4.9 0.67 1.4 1.9 0.38 1.2 0.021 0.17 <2 <10 <8 590 

20
Appendix 7. Results of ICP-AES analyses —Continued.

Sample Al Ca Fe K Mg Na P Ti Ag As Au Ba 

wt. % wt. % wt. % wt. % wt. % wt. % wt. % wt. % ppm ppm ppm ppm 

SH-2/28-AD 4.6 0.75 2.3 1.6 0.42 1.0 0.027 0.23 <2 <10 <8 370 

SH-2/29-AD 4.8 0.88 1.9 1.5 0.43 1.1 0.026 0.24 <2 <10 <8 1100 SH-2/30-AD 4.8 0.83 1.5 1.7 0.40 1.2 0.024 0.19 <2 <10 <8 1100 SH-2/31-AD 4.7 1.1 2.1 1.4 0.49 1.1 0.027 0.24 <2 <10 <8 840 SH-2/32-AD 11.0 0.4 6.5 3.0 1.4 0.31 0.056 0.48 <2 <10 <8 770 SH-2/33-AD 6.2 0.47 3.8 1.2 0.38 0.22 0.023 0.37 <2 <10 <8 443 SH-2/34-AD 7.4 0.47 3.8 2.2 0.98 0.77 0.014 0.42 <2 22 <8 630 SH-2/35-AD 4.9 1.4 2.4 1.5 0.59 1.2 0.048 0.32 <2 <10 <8 370 SH-2/36-AD 4.5 0.88 1.6 1.7 0.38 1.2 0.029 0.20 <2 <10 <8 580 SH-2/37-AD 6.1 0.44 3.3 1.8 0.76 0.94 0.028 0.38 <2 <10 <8 510 

21
Appendix 7. Results of ICP-AES analyses—Continued

Sample Cd Ce Co Cr Cu Eu Ga Ho La Li Mn Mo 

ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm 

SH-2/1-AD <2 86 19 94 33 <2 21 <4 44 49 430 2 

SH-2/2-AD <2 75 12 53 10 <2 15 <4 40 24 600 <2 SH-2/3-AD <2 86 17 97 36 <2 14 <4 42 36 840 <2 SH-2/4-AD <2 73 10 47 4.1 <2 10 <4 35 18 490 <2 SH-2/5-AD <2 80 7.7 43 3.5 <2 9.3 <4 39 16 500 <2 SH-2/6-AD <2 66 8.3 40 4.5 <2 9.1 <4 33 17 470 <2 SH-2/7-AD <2 56 5.9 28 6.8 <2 6.9 <4 27 12 390 <2 SH-2/8-AD <2 44 7.3 29 18 <2 5.2 <4 22 14 440 <2 SH-2/9-AD <2 70 21 110 52 <2 17 <4 34 56 470 <2 

SH-2/10-AD <2 29 48 12 10 <2 <4 <4 14 12 2800 <2 SH-2/11-AD <2 54 5.3 24 2.1 <2 8.4 <4 26 14 350 <2 SH-2/12-AD <2 36 16 90 22 <2 18 <4 19 31 510 <2 SH-2/13-AD <2 69 7.8 46 4.3 <2 9.4 <4 33 14 300 <2 SH-2/14-AD <2 53 8.7 48 6 <2 11 <4 25 15 310 <2 SH-2/15-AD <2 69 11 49 30 <2 <4 <4 33 20 1100 <2 SH-2/16-AD <2 37 3.9 19 36 <2 6.8 <4 17 9.6 110 <2 SH-2/17-AD <2 55 8.2 36 4.8 <2 11 <4 25 16 260 <2 SH-2/18-AD <2 74 6.3 36 12 <2 8.3 <4 34 14 420 <2 SH-2/19-AD <2 56 7.8 32 6.2 <2 7.6 <4 27 16 490 <2 SH-2/20-AD <2 44 5.2 19 3.5 <2 9.3 <4 21 12 240 <2 SH-2/21-AD <2 67 5.5 22 2.4 <2 7.8 <4 31 13 350 <2 SH-2/22-AD <2 52 6.4 28 3.6 <2 8.9 <4 24 15 330 <2 SH-2/23-AD <2 43 10 33 7.4 <2 5.2 <4 21 18 820 <2 SH-2/24-AD <2 58 10 39 7.1 <2 10 <4 27 20 400 <2 SH-2/25-AD <2 59 8 35 4.5 <2 8.1 <4 28 18 580 <2 SH-2/26-AD <2 29 7.9 20 3.1 <2 <4 <4 14 15 1300 <2 SH-2/27-AD <2 44 6.3 28 42 <2 9.9 <4 21 16 270 <2 

22
Appendix 7. Results of ICP-AES analyses—Continued

Sample Cd Ce Co Cr Cu Eu Ga Ho La Li Mn Mo 

ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm 

SH-2/28-AD <2 73 7.0 36 2.3 <2 <4 <4 34 15 980 <2 

SH-2/29-AD <2 82 6.1 36 6.6 <2 6.7 <4 39 14 580 <2 SH-2/30-AD <2 49 2.4 29 3.1 <2 9.6 <4 26 16 320 <2 SH-2/31-AD <2 86 3.8 40 4.7 <2 9.7 <4 46 14 650 <2 SH-2/32-AD <2 79 24 80 41 2 30 <4 41 67 610 3.4 SH-2/33-AD <2 87 13 77 34 <2 14 <4 40 46 1100 <2 SH-2/34-AD <2 73 16 77 76 <2 15 <4 38 32 340 2.2 SH-2/35-AD <2 110 6.6 38 3.2 <2 10 <4 58 14 680 <2 SH-2/36-AD <2 67 4.0 29 3.0 <2 9 <4 36 15 390 <2 SH-2/37-AD <2 73 16 73 61 <2 17 <4 38 37 750 <2 

23
Appendix 7. Results of ICP-AES analyses—Continued

Sample Pb Sc Sn Sr Ta Th U V Y Yb Zn 

ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm 

SH-2/1-AD 25 14 <5 110 <20 21 <100 100 21 2.3 83 

SH-2/2-AD 17 9.4 <5 140 <20 17 <100 66 21 2.4 48 SH-2/3-AD 25 15 <5 140 <20 nr <100 100 23 2.4 91 SH-2/4-AD 21 9.2 <5 150 <20 nr <100 60 19 2.0 44 SH-2/5-AD 18 8.6 <5 160 <20 nr <100 55 21 2.3 38 SH-2/6-AD 19 7.6 <5 150 <20 nr <100 48 16 1.8 40 SH-2/7-AD 18 5.8 <5 150 <20 nr <100 34 13 1.5 28 SH-2/8-AD 13 4.7 <5 78 <20 nr <100 30 10 1.2 34 SH-2/9-AD 39 16 <5 130 <20 nr <100 120 20 2.2 110 

SH-2/10-AD 9.4 3.9 <5 76 <20 nr <100 22 7.6 <1 30 SH-2/11-AD 17 5.4 <5 150 <20 nr <100 34 13 1.4 31 SH-2/12-AD 24 12 <5 120 <20 nr <100 85 14 1.5 96 SH-2/13-AD 18 7.3 <5 120 <20 nr <100 57 18 1.8 32 SH-2/14-AD 20 7.7 <5 130 <20 nr <100 52 15 1.5 46 SH-2/15-AD 19 7.9 <5 90 <20 nr <100 56 17 1.8 76 SH-2/16-AD 19 3.2 <5 100 <20 nr <100 23 8.9 <1 77 SH-2/17-AD 23 6.2 <5 140 <20 nr <100 44 14 1.6 34 SH-2/18-AD 21 7.6 <5 140 <20 nr <100 50 19 2.2 73 SH-2/19-AD 19 6.2 <5 120 <20 nr <100 42 14 1.6 38 SH-2/20-AD 22 4.9 <5 130 <20 nr <100 33 12 1.3 33 SH-2/21-AD 19 5.6 <5 120 <20 nr <100 36 16 1.8 25 SH-2/22-AD 21 5.7 <5 120 <20 nr <100 38 12 1.3 29 SH-2/23-AD 22 6.4 <5 120 <20 nr <100 40 11 1.3 74 SH-2/24-AD 19 7.7 <5 130 <20 nr <100 52 15 1.6 49 SH-2/25-AD 19 7.3 <5 130 <20 nr <100 50 16 1.6 39 SH-2/26-AD 18 4.5 <5 110 <20 nr <100 28 8.2 <1 30 SH-2/27-AD 21 5.1 <5 130 <20 nr <100 35 11 1.2 51 

24
Appendix 7. Results of ICP-AES analyses—Continued

Sample Pb Sc Sn Sr Ta Th U V Y Yb Zn 

ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm 

SH-2/28-AD 17 7.0 <5 120 <20 nr <100 45 18 2.0 29 

SH-2/29-AD 18 7.6 <5 140 <20 nr <100 48 21 2.5 34 SH-2/30-AD 18 5.6 23 160 <20 10 <100 40 12 1.3 26 SH-2/31-AD 15 8.3 6.7 150 <20 18 <100 50 22 3.0 28 SH-2/32-AD 34 18 5.4 92 <20 25 <100 140 22 2.5 120 SH-2/33-AD 24 11 30 51 <20 20 <100 100 19 2.1 48 SH-2/34-AD 26 12 8 93 <20 17 <100 87 19 2.2 110 SH-2/35-AD 16 9.3 16 140 <20 24 <100 61 29 3.6 32 SH-2/36-AD 19 5.8 <5 130 <20 14 <100 39 16 1.8 24 SH-2/37-AD 24 9.6 <5 91 <20 16 <100 71 16 1.8 94 

25
Appendix 8. Results of Energy Dispersive X-ray Fluorescence (EDXRF) analyses of air-dried sediment samples re

2 borehole at Rajoir, Bangladesh. [David Siems and Tammy Hannah, USGS, Analysts; wt.% weight percent; ppm, parts per million] 

Sample Ag As Ba Bi Br Cd Ce Cr Cs Cu Ga 

ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm 

SH-2/1-AD <1 3 530 <5 6 <1 90 90 11 37 19 

SH-2/2-AD <1 2 400 <5 <1 <1 93 53 6 19 15 SH-2/3-AD <1 3 520 <5 <1 <1 86 97 10 51 17 SH-2/4-AD <1 <2 410 <5 <1 <1 71 46 8 19 12 SH-2/5-AD <1 <2 390 <5 <1 <1 80 47 7 20 12 SH-2/6-AD <1 <2 410 <5 <1 <1 71 37 8 19 12 SH-2/7-AD <1 <2 360 <5 <1 <1 60 28 5 20 9 SH-2/8-AD <1 <2 290 <5 <1 <1 47 29 <5 41 6 SH-2/9-AD <1 9 580 <5 1 <1 71 110 15 65 20 

SH-2/10-AD <1 <2 250 <5 <1 <1 29 17 <5 47 7 SH-2/11-AD <1 <2 380 <5 <1 <1 54 24 <5 18 10 SH-2/12-AD <1 <2 530 <5 1 <1 35 84 18 37 18 SH-2/13-AD <1 <2 390 <5 <1 <1 71 42 6 21 11 SH-2/14-AD <1 <2 440 <5 1 <1 58 43 8 21 10 SH-2/15-AD <1 3 390 <5 2 <1 73 52 6 47 13 SH-2/16-AD <1 <2 420 <5 <1 <1 61 20 7 48 8 SH-2/17-AD <1 <2 420 <5 <1 <1 57 34 8 20 12 SH-2/18-AD <1 <2 410 <5 <1 <1 74 36 5 27 11 SH-2/19-AD <1 <2 420 <5 <1 <1 61 35 9 25 10 SH-2/20-AD <1 <2 470 <5 <1 <1 73 28 7 18 9 SH-2/21-AD <1 <2 480 <5 <1 <1 73 29 5 19 9 SH-2/22-AD <1 <2 580 <5 <1 <1 61 33 7 18 10 SH-2/23-AD <1 2 530 <5 <1 <1 49 33 6 26 11 SH-2/24-AD <1 <2 590 <5 <1 <1 63 42 11 23 12 SH-2/25-AD <1 <2 440 <5 <1 <1 34 23 7 18 8 SH-2/26-AD <1 <2 440 <5 <1 <1 32 23 <5 19 10 SH-2/27-AD <1 <2 650 <5 <1 <1 50 30 10 51 10 

26
Appendix 8. Results of EDXRF analyses—Continued.

Sample Ag As Ba Bi Br Cd Ce Cr Cs Cu Ga 

ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm 

SH-2/28-AD <1 <2 420 <5 1 <1 85 40 8 19 10 

SH-2/29-AD <1 <2 1200 <5 <1 <1 90 43 12 22 11 SH-2/30-AD <1 <2 1200 <5 <1 <1 64 31 14 9 10 SH-2/31-AD <1 <2 910 <5 <1 <1 100 36 9 11 11 SH-2/32-AD <1 6 660 <5 <1 <1 78 120 18 45 24 SH-2/33-AD <1 4 420 <5 <1 <1 110 75 9 41 16 SH-2/34-AD <1 21 610 <5 <1 <1 89 85 11 74 18 SH-2/35-AD <1 <2 370 <5 <1 <1 130 36 5 12 11 SH-2/36-AD <1 <2 500 <5 <1 <1 87 87 7 64 13 SH-2/37-AD <1 7 420 <5 1 <1 85 40 8 19 10 

27
Appendix 8. Results of EDXRF analyses—Continued.

Sample Mo Nb Nd Ni Pb Rb Sb Se Sn Sr Th 

ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm 

SH-2/1-AD <2 16 40 53 25 180 <2 <1 5 110 19 

SH-2/2-AD <2 12 44 37 19 110 <2 <1 3 140 16 SH-2/3-AD <2 16 30 54 25 150 <2 <1 5 140 19 SH-2/4-AD <2 10 26 32 19 110 <2 <1 3 170 9 SH-2/5-AD <2 10 29 30 17 95 <2 <1 3 170 15 SH-2/6-AD <2 8 32 28 18 100 <2 <1 2 170 10 SH-2/7-AD <2 6 33 21 16 78 <2 <1 <2 160 9 SH-2/8-AD <2 6 22 20 14 70 <2 <1 <2 89 9 SH-2/9-AD <2 14 36 71 37 170 <2 <1 4 140 18 

SH-2/10-AD <2 5 <10 23 13 65 <2 <1 2 83 5 SH-2/11-AD <2 6 16 19 18 88 <2 <1 2 160 9 SH-2/12-AD <2 13 16 50 22 210 <2 <1 5 120 5 SH-2/13-AD <2 9 30 26 17 87 <2 <1 2 140 11 SH-2/14-AD <2 9 26 28 19 110 <2 <1 3 140 9 SH-2/15-AD <2 10 34 36 18 100 <2 <1 3 110 13 SH-2/16-AD 2 5 44 14 19 88 <2 <1 2 110 8 SH-2/17-AD <2 8 26 24 18 100 <2 <1 2 150 6 SH-2/18-AD <2 9 27 24 18 87 <2 <1 2 160 13 SH-2/19-AD <2 7 32 24 18 100 <2 <1 2 140 9 SH-2/20-AD <2 8 36 18 18 85 <2 <1 <2 140 14 SH-2/21-AD <2 7 29 23 17 84 <2 <1 <2 140 11 SH-2/22-AD <2 7 30 22 18 93 <2 <1 2 140 8 SH-2/23-AD <2 7 24 31 23 110 <2 <1 2 130 7 SH-2/24-AD <2 10 30 36 20 120 <2 <1 3 140 13 SH-2/25-AD <2 6 14 21 18 100 <2 <1 <2 120 5 SH-2/26-AD <2 6 15 23 19 100 <2 <1 2 120 6 SH-2/27-AD <2 6 22 19 18 98 <2 <1 3 140 7 

28
Appendix 8. Results of EDXRF analyses—Continued.

Sample Mo Nb Nd Ni Pb Rb Sb Se Sn Sr Th 

ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm 

SH-2/28-AD <2 9 40 25 17 88 <2 <1 2 130 15 

SH-2/29-AD <2 9 46 25 16 77 <2 <1 3 160 13 SH-2/30-AD 2 8 37 20 19 89 <2 <1 2 160 9 SH-2/31-AD <2 8 43 24 16 69 <2 <1 3 160 16 SH-2/32-AD 2 19 32 61 36 200 <2 <1 6 90 24 SH-2/33-AD <2 16 35 45 24 100 <2 <1 4 54 19 SH-2/34-AD <2 17 48 47 26 130 <2 <1 5 97 19 SH-2/35-AD <2 12 47 22 16 76 <2 <1 3 150 22 SH-2/36-AD <2 16 41 49 19 110 <2 <1 4 96 15 SH-2/37-AD <2 9 40 25 17 88 <2 <1 2 130 15 

29
Appendix 8. Results of EDXRF analyses—Continued.

Sample V W Y Zn Zr 

ppm ppm ppm ppm ppm 

SH-2/1-AD 110 <5 35 84 108 

SH-2/2-AD 71 <5 33 55 71 SH-2/3-AD 110 <5 35 83 107 SH-2/4-AD 56 <5 25 48 56 SH-2/5-AD 53 <5 26 41 53 SH-2/6-AD 45 <5 19 43 45 SH-2/7-AD 33 <5 17 33 33 SH-2/8-AD 28 <5 16 46 28 SH-2/9-AD 110 <5 27 103 113 

SH-2/10-AD 24 160 12 49 24 SH-2/11-AD 30 <5 16 35 30 SH-2/12-AD 91 <5 17 93 91 SH-2/13-AD 55 <5 21 34 55 SH-2/14-AD 53 <5 18 50 53 SH-2/15-AD 62 <5 26 78 62 SH-2/16-AD 24 <5 15 81 24 SH-2/17-AD 43 <5 18 36 43 SH-2/18-AD 52 <5 25 77 52 SH-2/19-AD 41 <5 17 40 41 SH-2/20-AD 34 <5 22 30 34 SH-2/21-AD 37 <5 19 30 37 SH-2/22-AD 36 <5 16 33 36 SH-2/23-AD 41 <5 14 78 41 SH-2/24-AD 51 <5 23 54 51 SH-2/25-AD 31 <5 13 31 31 SH-2/26-AD 32 <5 13 31 32 SH-2/27-AD 35 <5 15 52 35 

30
31

W Y Zn Zr 

Appendix 8. Results of EDXRF analyses—Continued.

Sample V 

ppm ppm ppm m ppm 

<5 25 36 43 

pp

SH-2/28-AD 43 

SH-2/29-AD 52 <5 26 40 52 

<5 16 36 38 <5 28 44 54 

 140 <5 35 2 0  105 <5 34 59 5 

<5 36 7 99 <5 37 43 61 <5 33 97 85 <5 25 36 43 

SH-2/30-AD 38 SH-2/31-AD 54 SH-2/32-AD 11 14SH-2/33-AD 10SH-2/34-AD 99 10SH-2/35-AD 61 SH-2/36-AD 85 SH-2/37-AD 43 
Appendix 9. Results of arsenic analyses by Hydride Generation Atomic Absorption 

Spectrophotometry (HGAAS) of air-dried sediment samples from the SH-2 borehole, Rajoir, 

Bangladesh. 

 [Zoe Ann Brown, USGS, Analyst; ppm, parts per million] 

Sample As 

(ppm) 

SH-2/1-AD 3.9 

SH-2/2-AD 2.5 

SH-2/3-AD 4.2 

SH-2/4-AD 1.9 

SH-2/5-AD 1.3 

SH-2/6-AD 1.2 

SH-2/7-AD 1.2 

SH-2/8-AD 2.7 

SH-2/9-AD 11.0 

SH-2/10-AD 1.6 

SH-2/11-AD 1.1 

SH-2/12-AD 1.5 

SH-2/13-AD 0.8 

SH-2/14-AD 0.7 

SH-2/15-AD 4.8 

SH-2/16-AD 1.0 

SH-2/17-AD 0.7 

SH-2/18-AD 1.1 

SH-2/19-AD 0.7 

SH-2/20-AD 0.6 

SH-2/21-AD 0.6 

SH-2/22-AD 0.8 

SH-2/23-AD 2.4 

SH-2/24-AD 1.0 

SH-2/25-AD 1.8 

SH-2/26-AD 0.9 

SH-2/27-AD 0.9 

SH-2/28-AD 1.1 

SH-2/29-AD 0.8 

SH-2/30-AD 0.7 

SH-2/31-AD 0.6 

SH-2/32-AD 6.5 

SH-2/33-AD 5.1 

SH-2/34-AD 21.0 

SH-2/35-AD 0.6 

SH-2/36-AD 1.2 

SH-2/37-AD 8.1 

32
33

Appendix 10. Total iron and ferrous iron extracted from preserved sediment samples from the SH-2 

borehole, Rajoir, Bangladesh using a solution of 0.5 N HCl. 

[Values calculated based on dry weight of the post-extraction residue; wt.%, weight percent; Ferrous/Total Iron values 

>1 are within the 5 % relative error]

Total Iron Ferrous Ferrous / Total Iron 

(wt. %) (wt.%) 

SH-2/1-P 0.36 0.34 0.95 

SH-2/2-P 0.65 0.59 0.92 

SH-2/3-P 0.84 0.75 0.90 

SH-2/4-P 0.36 0.32 0.89 

SH-2/5-P 0.22 0.20 0.91 

SH-2/6-P 0.40 0.37 0.91 

SH-2/7-P 0.19 0.19 0.96 

SH-2/8-P 0.29 0.26 0.89 

SH-2/9-P 1.13 1.10 0.98 

SH-2/11-P 0.13 0.12 0.92 

SH-2/12-P 0.82 0.79 0.96 

SH-2/13-P 0.66 0.63 0.95 

SH-2/14-P 0.30 0.27 0.90 

SH-2/15-P 0.63 0.60 0.96 

SH-2/16-P 0.07 0.07 0.91 

SH-2/17-P 0.32 0.29 0.93 

SH-2/18-P 0.21 0.19 0.88 

SH-2/19-P 0.24 0.22 0.93 

SH-2/20-P 0.14 0.13 0.96 

SH-2/21-P 0.10 0.09 0.95 

SH-2/22-P 0.21 0.20 0.97 

SH-2/23-P 0.82 0.73 0.90 

SH-2/24-P 0.55 0.53 0.97 

SH-2/25-P 0.62 0.60 0.97 

SH-2/26-P 0.22 0.21 0.95 

SH-2/27-P 0.20 0.19 0.96 

SH-2/28-P 0.63 0.61 0.97 

SH-2/29-P 0.11 0.10 0.98 

SH-2/30-P 0.15 0.13 0.92 

SH-2/31-P 0.13 0.12 0.97 

SH-2/32-P 0.11 0.10 0.93 

SH-2/33-P 1.02 1.03 1.01 

SH-2/34-P 0.93 0.96 1.03 

SH-2/35-P 0.13 0.14 1.03 

SH-2/36-P 0.10 0.10 0.98 

SH-2/37-P 0.70 0.69 0.99 
Appendix 11. Results of analyses of 0.5 N HCl extract solutions after reaction with preserved sediment samples fr

Rajoir, Bangladesh. Concentrations determined by ICP-AES unless otherwise indicated. 

[Paul Briggs and Z. A. Brown, USGS, Analyses; *, determined by HGAAS. Values calculated based on dry weight of the post-extractiomillion]

Sample Al As* B Ba Be Ca Cd Co Cr Cu 

(ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) 

SH-2/1-P 2600 1.0 2.7 20 0.4 1600 0.5 4.4 4.0 13 

SH-2/2-P 2600 0.2 0.9 23 0.2 3400 <0.2 3.6 4.3 6 SH-2/3-P 3300 1.5 1.6 44 0.4 3900 0.2 5.1 5.2 28 SH-2/4-P 1400 0.4 1.6 23 0.1 850 <0.2 2.4 3.4 3 SH-2/5-P 1100 0.2 0.8 16 0.1 840 <0.2 1.7 1.9 2 SH-2/6-P 1600 0.2 0.6 28 0.2 900 <0.2 2.4 2.8 4 SH-2/7-P 580 0.2 2.3 13 0.1 460 <0.2 1.2 1.3 17 SH-2/8-P 770 0.2 0.6 22 0.1 730 <0.2 1.6 2.0 11 SH-2/9-P 570 0.7 1.9 140 0.8 2600 0.2 8.2 7.5 11 

SH-2/11-P 540 0.1 0.7 9 0.1 530 <0.2 0.8 1.4 1 SH-2/12-P 2200 0.2 0.5 40 0.4 780 <0.2 3.2 14.9 10 SH-2/13-P 1700 <0.1 1.6 36 0.4 880 <0.2 3.7 4.6 88 SH-2/14-P 930 0.1 2.5 19 0.1 820 <0.2 1.5 3.0 31 SH-2/15-P 1300 0.7 1.1 38 0.6 1300 <0.2 6.0 2.0 14 SH-2/16-P 330 0.1 0.4 6 0.1 260 <0.2 1.1 1.4 1 SH-2/17-P 180 0.1 0.8 22 0.3 980 <0.2 4.8 4.3 33 SH-2/18-P 1100 0.2 1.3 17 0.1 1000 <0.2 2.0 2.5 11 SH-2/19-P 1100 0.1 0.8 16 0.2 580 <0.2 1.8 2.9 11 SH-2/20-P 640 <0.1 1.2 9 0.1 560 <0.2 1.4 1.5 1 SH-2/21-P 460 <0.1 0.5 10 0.1 510 <0.2 1.0 1.6 1 SH-2/22-P 740 0.1 0.6 10 0.1 640 <0.2 1.9 3.3 2 SH-2/23-P 1100 6.2 0.6 37 0.4 1000 0.7 18 1.1 6 SH-2/24-P 2700 0.2 1.5 28 0.4 970 <0.2 8.3 4.9 4 SH-2/25-P 1500 0.5 0.9 21 0.3 950 <0.2 3.2 2.9 3 SH-2/26-P 1000 0.1 1.0 20 0.2 890 <0.2 1.8 2.7 2 SH-2/27-P 970 0.1 0.7 220 0.2 630 <0.2 1.8 2.0 11 

34
Appendix 11. Results of analyses of 0.5 N HCl extract solutions—Continued

Sample Al As* B Ba Be Ca Cd Co Cr Cu 

(ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) 

SH-2/28-P 990 0.1 1.0 40 0.2 750 <0.2 2.3 1.7 20 

SH-2/29-P 580 0.1 0.8 8 0.1 590 <0.2 1.2 1.6 1 SH-2/30-P 630 0.1 1.1 200 0.2 620 <0.2 1.4 1.0 16 SH-2/31-P 770 0.1 2.0 220 0.2 780 <0.2 2.3 1.8 62 SH-2/32-P 1200 <0.1 1.8 110 0.7 3000 <0.2 0.4 0.4 6 SH-2/33-P 1100 0.4 1.2 77 0.7 2900 <0.2 4.1 0.7 21 SH-2/34-P 3800 0.1 1.2 73 0.8 1600 <0.2 4.5 7.7 21 SH-2/35-P 530 0.8 1.1 9 0.1 1100 <0.2 0.9 1.5 1 SH-2/36-P 500 0.1 0.7 27 0.1 730 <0.2 1.4 1.6 1 SH-2/37-P 2100 0.2 1.3 36 0.5 1800 <0.2 4.9 3.9 9 

35
Appendix 11. Results of analyses of 0.5 N HCl extract solutions—Continued

Sample Li Mg Mn Mo Na Ni P Pb Sb 

(ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) 

SH-2/1-P 4.1 1900 64 0.33 96 11 360 8.0 <2 

SH-2/2-P 4.3 2900 270 0.33 72 10 370 5.2 <2 SH-2/3-P 4.0 3900 440 0.31 280 13 480 13 <2 SH-2/4-P 2.5 1000 75 0.29 210 8 270 3.3 <2 SH-2/5-P 2.1 710 66 0.33 130 6 320 2.6 <2 SH-2/6-P 2.9 1300 96 0.26 250 7 190 4.3 <2 SH-2/7-P 1.0 340 39 0.26 180 3 200 2.4 <2 SH-2/8-P 1.5 520 330 0.26 320 3 130 3.6 <2 SH-2/9-P 7.5 3800 120 0.33 950 18 320 23 <2 

SH-2/11-P 1.0 360 33 0.27 240 3 140 2.4 <2 SH-2/12-P 2.2 1900 71 0.27 630 13 110 7.7 <2 SH-2/13-P 1.8 1200 160 0.27 590 9 170 7.0 <2 SH-2/14-P 1.5 690 57 0.26 700 4 180 3.8 <2 SH-2/15-P 2.0 1300 340 0.29 1100 10 110 11 <2 SH-2/16-P 0.4 240 7 0.28 100 2 35 2.0 <2 SH-2/17-P 2.2 1200 54 0.27 250 10 210 5.6 <2 SH-2/18-P 1.6 700 47 0.27 260 5 310 3.7 <2 SH-2/19-P 1.8 800 68 0.27 250 6 130 2.6 <2 SH-2/20-P 1.0 580 34 0.26 170 4 110 2.3 <2 SH-2/21-P 0.7 390 17 0.28 190 3 110 2.5 <2 SH-2/22-P 1.0 570 82 0.27 230 6 160 2.8 <2 SH-2/23-P 1.5 860 970 0.27 230 39 230 26 <2 SH-2/24-P 3.6 2200 160 0.29 360 17 160 5.9 <2 SH-2/25-P 2.0 1200 380 0.29 210 7 290 3.4 <2 SH-2/26-P 1.3 810 46 0.27 170 6 290 2.9 <2 SH-2/27-P 1.6 730 54 0.29 340 5 130 2.4 <2 

36
Appendix 11. Results of analyses of 0.5 N HCl extract solutions—Continued

Sample Li Mg Mn Mo Na Ni P Pb Sb 

(ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) 

SH-2/28-P 1.6 740 570 0.3 270 4 200 4.0 <2 

SH-2/29-P 1.0 430 28 0.3 320 3 190 2.4 <2 SH-2/30-P 1.1 450 61 0.3 300 3 150 3.0 <2 SH-2/31-P 1.1 500 28 0.3 350 3 170 2.6 <2 SH-2/32-P 1.2 1700 51 0.3 850 1 88 13 <2 SH-2/33-P 0.9 1230 540 0.3 440 3 110 18 <2 SH-2/34-P 3.5 2900 91 0.3 470 9 44 13 <2 SH-2/35-P 0.9 350 37 0.3 120 3 440 2.3 <2 SH-2/36-P 0.9 330 23 0.3 150 3 260 1.6 <2 

SH-2/37-P 3.6 1700 540 0.3 730 11 180 11 <2 

37
Appendix 11. Results of analyses of 0.5 N HCl extract solutions—Continued

Sample Sr Ti V Zn 

(ppm) (ppm) (ppm) (ppm) 

SH-2/1-P 10 54 14 32 

SH-2/2-P 8 170 7.1 19 SH-2/3-P 12 140 13 24 SH-2/4-P 3 100 4.2 9 SH-2/5-P 3 73 3.0 8 SH-2/6-P 5 95 5.0 11 SH-2/7-P 2 12 1.7 13 SH-2/8-P 5 20 2.9 11 SH-2/9-P 23 <1 20 37 

SH-2/11-P 2 31 1.3 4 SH-2/12-P 6 36 8.6 19 SH-2/13-P 5 <1 7.2 53 SH-2/14-P 5 <1 2.7 27 SH-2/15-P 9 <1 6.1 19 SH-2/16-P 2 6 0.9 4 SH-2/17-P 5 83 6.8 27 SH-2/18-P 5 77 3.2 13 SH-2/19-P 4 76 3.1 14 SH-2/20-P 4 32 1.8 6 SH-2/21-P 3 17 1.5 4 SH-2/22-P 3 55 2.6 7 SH-2/23-P 4 53 9.0 13 SH-2/24-P 6 150 8.8 22 SH-2/25-P 3 150 7.2 13 SH-2/26-P 4 92 3.3 8 SH-2/27-P 10 62 2.2 15 

38
39

Ti V Zn 

Appendix 11. Results of analyses of 0.5 N HCl extract solutions—Continued

Sample Sr 

 (p ) ) ) ) 

19 

pm (ppm (ppm (ppm

SH-2/28-P 4 67 5.2 

SH-2/29-P 2 25 1.8 5 

5 15 6 45 

6 9 

9 15 

0 29 5 5 3 5 6 20 

SH-2/30-P 10 25 1.SH-2/31-P 12 12 1.SH-2/32-P 28 <1 4.SH-2/33-P 17 <1 5.SH-2/34-P 15 71 8.SH-2/35-P 3 29 1.SH-2/36-P 3 25 

13 9 

1.

SH-2/37-P 4.
```Appendix 12. Concentrations of acid-volatile sulfide (AVS), reducible sulfide (DI), and acidsoluble sulfate (SO4

) in selected preserved sediment samples from the SH-2 borehole, Rajoir, 

Bangladesh. 

[ppm, parts per million] 

Sample Sulfide -AVS 

(ppm) 

Sulfide -DI 

(ppm) 

Acid-soluble-SO4 

(ppm) 

SH-2/1-P 5250 9580 100 

SH-2/2-P 390 350 50 

SH-2/3-P 70 210 130 

SH-2/9-P 80 214 60 

SH-2/15-P 220 400 50 

SH-2/29-P 10 30 50 

SH-2/34-P 30 150 50 

SH-2/37-P 20 300 30 

40