U.S. Department of the Interior

U.S. Geological Survey

Open-File Report 2014-1096

Prepared in cooperation with the National Park Service, Glen Canyon National Recreation Area

Sediment and Water Chemistry of the San Juan River and 

Escalante River Deltas of Lake Powell, Utah, 2010–2011
COVER

U.S. Geological Survey employees handling a sediment core on the San Juan River in Utah. Photograph by Robert J. 

Hart.
Sediment and Water Chemistry of the San 

Juan River and Escalante River Deltas of 

Lake Powell, Utah, 2010–2011

By N.J. Hornewer

Prepared in cooperation with the National Park Service, Glen Canyon 

National Recreation Area

Open-File Report 2014–1096

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: 2014

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Suggested citation:

Hornewer, N.J., 2014, Sediment and water chemistry of the San Juan River and Escalante River deltas of Lake Powell, 

Utah, 2010–2011: U.S. Geological Survey Open-File Report 2014-1096, 7 p., http://dx.doi.org/10.3133/ofr20141096.

ISSN 2331-1258 (online)
 iii

Acknowledgments

The author would like to thank Mark Anderson, aquatic ecologist, and Carolyn Hackbarth, 

hydrologic technician, from the National Park Service Glen Canyon National Recreation Area 

for their significant contribution and assistance with this study. In addition, thanks to Robert 

Hart from the U.S. Geological Survey Arizona Water Science Center (AzWSC) and Howard Taylor from the U.S. Geological Survey-Water Resources Discipline-National Research 

Program (NRP), Boulder, Colorado for developing and designing this study; Ronald Antweiler 

from NRP for his guidance and expertise with field-collection and analytical methods; David 

Roth from NRP and Corey Sannes from the AzWSC for their expertise with operating the 

coring rig; Kurt Schonauer from the AzWSC for his guidance; Greg Fisk from the AzWSC for 

his logistical expertise; Terry Plowman, chemist from NRP, for her contribution with sample 

processing and analyses; and William Vernieu, hydrologist from U.S. Geological Survey Grand 

Canyon Monitoring and Research Center, for his assistance with processing and providing 

bathymetric-survey information for the deltas.
iv 

Contents

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

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

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

Summary of Core and Water Analyses ......................................................................................................6

Consideration for Future Studies ................................................................................................................6

Summary..........................................................................................................................................................6

References Cited............................................................................................................................................7

Appendixes ......................................................................................................................... Available Online

Appendix A. Sediment Core Information and Sediment-Chemistry and Water-Sample 

Results for the San Juan River delta, Lake Powell, Utah, 2010.

Appendix B. Sediment Core Information and Sediment-Chemistry and Water-Sample 

Results for the Escalante River delta, Lake Powell, Utah, 2011.

Figures

1. Map showing location of study area and core sampling sites, San Juan River and 

 Escalante River deltas, Lake Powell, southeastern Utah ......................................................2

2. Sediment-accumulation profiles and coring locations in the deltas of the San Juan River

 (A) and Escalante River (B) inflow reaches to Lake Powell, Utah, and sediment and 

lake elevations for 1986 through 2011 .......................................................................................3

3. Logs showing cores, core sections and lengths, subsample locations, and composited 

samples collected from the San Juan River and Escalante River deltas, Lake Powell, 

Utah.................................................................................................................................................5
 v

Conversion Factors and Datums

Inch/Pound to SI

Multiply By To obtain

Length

millimeter (mm) 0.03937 inch (in.)

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi)

meter (m) 1.094 yard (yd) 

Mass

gram (g) 0.03527 ounce, avoirdupois (oz)

kilogram (kg) 2.205 pound avoirdupois (lb)

Radioactivity

becquerel per liter (Bq/L) 27.027 picocurie per liter (pCi/L)

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

°F=(1.8×°C)+32

Abbreviated Water-Quality Units

Chemical concentration and water temperature are given only in metric units. Chemical 

concentration in water is given in milligrams per liter (mg/L), micrograms per liter (μg/L), or 

nanograms per liter (ng/L). Milligrams per liter is a unit expressing the solute mass (milligrams) 

per unit volume (liter) of water. One thousand micrograms per liter is equivalent to 1 milligram 

per liter. For concentrations less than 7,000 milligrams per liter, the numerical value is about the 

same as for concentration in parts per million. Specific conductance is given in microSiemens 

per centimeter at 25 degrees Celsius (μS/cm at 25 °C). Radioactivity is expressed in picocuries 

per liter (pCi/L) or picocuries per gram (pCi/g), which is the amount of radioactive decay producing 2.2 disintegrations per minute in a unit volume (liter) of water or mass (gram) of sediment. 

Chemical concentration in bottom sediment is given in grams per kilogram (g/kg), micrograms 

per gram (μg/g), milligrams per kilogram (mg/kg), or micrograms per kilogram (μg/kg). Grams 

per kilogram is equal to parts per thousand (ppt). Milligrams per kilogram and micrograms per 

gram are equal to parts per million (ppm). Micrograms per kilogram are equal to parts per billion 

(ppb).

Datums

Vertical coordinate information is referenced to the North American Vertical Datum of 1929 

(NAVD 29).

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).

Elevation, as used in this report, refers to distance above the vertical datum.

Sediment and Water Chemistry of the San Juan River and 

Escalante River Deltas of Lake Powell, Utah, 2010–2011

By N.J. Hornewer

Abstract 

Recent studies have documented the presence of trace 

elements, organic compounds including polycyclic aromatic 

hydrocarbons, and radionuclides in sediment from the 

Colorado River delta and from sediment in some side canyons 

in Lake Powell, Utah and Arizona. The fate of many of these 

contaminants is of significant concern to the resource managers 

of the National Park Service Glen Canyon National Recreation 

Area because of potential health impacts to humans and aquatic 

and terrestrial species. In 2010, the U.S. Geological Survey 

began a sediment-core sampling and analysis program in the 

San Juan River and Escalante River deltas in Lake Powell, 

Utah, to help the National Park Service further document the 

presence or absence of contaminants in deltaic sediment. 

Three sediment cores were collected from the San Juan 

River delta in August 2010 and three sediment cores and an 

additional replicate core were collected from the Escalante 

River delta in September 2011. Sediment from the cores was 

subsampled and composited for analysis of major and trace 

elements. Fifty-five major and trace elements were analyzed 

in 116 subsamples and 7 composited samples for the San Juan 

River delta cores, and in 75 subsamples and 9 composited 

samples for the Escalante River delta cores. Six composited 

sediment samples from the San Juan River delta cores and 

eight from the Escalante River delta cores also were analyzed 

for 55 low-level organochlorine pesticides and polychlorinated 

biphenyls, 61 polycyclic aromatic hydrocarbon compounds, 

gross alpha and gross beta radionuclides, and sediment-particle 

size. 

Additionally, water samples were collected from the 

sediment-water interface overlying each of the three cores 

collected from the San Juan River and Escalante River deltas. 

Each water sample was analyzed for 57 major and trace 

elements. 

Most of the major and trace elements analyzed were 

detected at concentrations greater than reporting levels for 

the sediment-core subsamples and composited samples. 

Low-level organochlorine pesticides and polychlorinated 

biphenyls were not detected in any of the samples. Only one 

polycyclic aromatic hydrocarbon compound was detected at a 

concentration greater than the reporting level for one San Juan 

composited sample. Gross alpha and gross beta radionuclides 

were detected at concentrations greater than reporting levels 

for all samples. Most of the major and trace elements analyzed 

were detected at concentrations greater than reporting levels for 

water samples. 

Introduction

Lake Powell, located in northeastern Arizona and 

southeastern Utah (fig. 1), is the second largest reservoir in the 

United States. The reservoir was created by the construction of 

Glen Canyon Dam, completed in March 1963, and impounds 

three major rivers: the Colorado, San Juan, and Escalante. 

Sediment transported by these rivers is primarily deposited as 

deltas in the inflow reaches to Lake Powell. Deltas formed by 

the Colorado, San Juan, and Escalante Rivers are active areas 

of sediment deposition and erosion and change over time. 

They are affected by hydrology, regional climate, reservoir 

operations, and fluctuating lake levels (Ferrari, 1988; Pratson 

and others, 2008).

Deltas are potential sinks for contaminants introduced 

through natural processes and human activities, which may 

sorb to sediment and sink in deposition areas. When deltaic 

sediment is reworked and transported farther into the lake, 

contaminants can be released into the water and become 

bioavailable and potentially harmful to humans and aquatic 

and terrestrial species, and may affect water quality in 

downstream portions of the reservoir (Hart and others, 2005; 

Potter and Drake, 1989; Vernieu, 1997). Sediment cores 

collected from the Colorado River delta as part of a U.S. 

Geological Survey (USGS) study done in 2001 documented 

the presence of trace elements, organic compounds including 

polycyclic aromatic hydrocarbons (PAHs), and radionuclides 

in the sediment (Hart and others, 2004, 2005). 

Glen Canyon National Recreation Area (Glen Canyon 

NRA) resource managers are concerned about these 

contaminants and their potential effects on humans and 

the environment. In 2010, the USGS began another study, 

supported by the USGS Office of Water Quality’s WaterQuality Assessment and Monitoring program and Glen 

Canyon NRA, to help Glen Canyon NRA resource managers 

document the presence or absence of these contaminants in 

deltaic sediment from the two other major tributaries to Lake 

Powell, the San Juan and Escalante Rivers.
2 Sediment and Water Chemistry of the San Juan River and Escalante River Deltas of Lake Powell, Utah, 2010–2011

110°45'0"W

37°15'0"N

0 5 MILES

0 5 KILOMETERS

Escalante 

River

San Juan

River

Core 1

Core 2

Core 3

Core 1

Core 2

Core 3

Base from U.S. Geological Survey 

digital data, 1:100,000, 2009 Universal Transverse Mercator projection, Zone 12 

River

ar C o ol do

Lake Powell

Study area

ARIZONA

UTAH

1.25 2.5

1.25 2.5

San Juan River sediment core site

Escalante River sediment core site

Boundary of Glen Canyon National Recreation Area

EXPLANATION

Figure 1. Map showing location of study area and core sampling sites, San Juan River and Escalante River deltas, Lake Powell, 

southeastern Utah.

The mouth of the San Juan River is approximately 

100 km upstream of Glen Canyon Dam. In 1986, in the reach 

of the river where the sediment cores were collected 

(54–65 km upstream of the mouth), approximately 15 m of 

sediment had been deposited since the construction of Glen 

Canyon Dam (fig. 2A; appendix A1; Ferrari, 1988). Between 

1986 and 2011, an additional 12 m of sediment was deposited 

(William Vernieu, Grand Canyon Monitoring and Research 

Center, written commun., October 12, 2012). The mouth of 

the Escalante River is approximately 117 km upstream of Glen 

Canyon Dam. By 1986, approximately 13 m of sediment had 

been deposited in the river reach where the sediment cores 

were collected (27–30 km upstream of the mouth) and by 

2011, an additional 9 m was deposited (fig. 2B; appendix B1; 

Ferrari, 1988; William Vernieu, Grand Canyon Monitoring and 

Research Center, written commun., October 12, 2012).
Introduction 

3

Figure 2. Sedimentaccumulation profiles and 

coring locations in the 

deltas of the San Juan River (A) and Escalante River (B) inflow reaches to Lake 

Powell, Utah, and sediment 

and lake elevations for 1986 

through 2011. Data from 

Ferrari, 1988; Vernieu, Grand 

Canyon Monitoring and 

Research Center, written 

commun., October 12, 2012. 

Vertical datum is NGVD 29.
4 Sediment and Water Chemistry of the San Juan River and Escalante River Deltas of Lake Powell, Utah, 2010–2011

The purpose of this report is to present sediment and 

water chemistry analytical results from three sediment cores 

collected from the San Juan River delta in 2010 and three 

sediment cores and one replicate core collected from the 

Escalante River delta in 2011, and water-sample analytical 

results collected from water overlying the sediment-water 

interface above each of the cores collected from the San Juan 

River and Escalante River deltas (fig. 1). Sediment samples 

were analyzed for 55 major and trace elements, 55 low-level 

organochlorine pesticide and polychlorinated biphenyls, 

61 polycyclic aromatic hydrocarbon compounds, gross alpha 

and gross beta radionuclides, and sediment-particle size. 

Water samples were analyzed for 57 major and trace elements. Site information, physical descriptions of the cores, 

summaries of analytical results, and complete analytical 

results for individual and composited samples are presented 

in spreadsheets in appendix A for the San Juan River delta 

and appendix B for the Escalante River delta.

Methods

This study uses the same coring equipment and follows 

the methodology used in a similar study examining contaminants in the Colorado River delta in Lake Powell by Hart and 

others (2005). Methods for this study are summarized below. 

For more detailed information on coring equipment and 

methods, and field-sample preservation, processing, analysis, 

and quality-control, refer to Hart and others (2005).

Sediment-coring locations for the San Juan River and 

Escalante River deltas were determined by reviewing recent 

channel-bottom surveys (measured using an echo sounder 

along the thalweg, or deepest part of the channel) conducted 

by the USGS-Grand Canyon Monitoring and Research 

Center (GCMRC) and results from a 1986 bathymetric 

survey conducted by the Bureau of Reclamation (fig. 2). 

Three coring locations were selected along the thalweg of 

each delta (fig. 1): 

•	 Core 1, the most upstream site, in an area where 

there was sufficient water depth (minimum of 

approximately 5 m) to safely deploy the corer; 

•	 Core 2, a middle site, in an area that was between 

the most upstream and downstream sites; and 

•	 Core 3, the most downstream site, in an area where 

the water depth would be less than approximately 

25 m (corer does not properly operate in greater 

depths). 

One replicate core was collected at the site of the Escalante 

Core 3 sample. Selected delta sediment-accumulation profile 

surveys (channel-bottom surveys) from 1986 to 2011, 

corresponding lake elevations during the surveys, and coring 

locations for the San Juan River and Escalante River deltas 

are shown in figure 2. A Global Positioning System (GPS) 

was used to record the locations of each coring site.

Appendixes A1 and B1 show information on each of 

the coring locations, sediment-core sample dates, times and 

lengths, and USGS site numbers and names for each coresample location for the San Juan River and Escalante River 

deltas, respectively. Section 1, the uppermost section, of 

San Juan sediment Core 2 was damaged during collection 

and therefore, sediment from this section was unusable for 

analysis. The length of this damaged section was estimated 

to be between 174 and 226 mm long with an average length 

of 200 mm, which is the estimate used to represent sediment 

thickness for section 1 in this report.

Once collected, the sediment cores were sectioned 

and frozen in the field and processed at the USGS-National 

Research Program (NRP) laboratory in Boulder, Colo. At the 

laboratory, the sections were thawed, physical descriptions 

of the strata within each section of the sediment cores were 

recorded (appendixes A2 and B2 for the San Juan River and 

Escalante River sediment cores, respectively), and the cores 

were sampled for analyses.

Two types of samples were collected from the sediment 

cores and are referred to as subsamples and composited 

samples (fig. 3). Subsamples are samples taken from 

various strata in the sediment core that may represent 

different sediment-chemistry properties and are analyzed 

individually. For composited samples each core was divided 

into two equal lengths and a longitudinal slice of sediment 

was removed from each length, one for the upper half and 

one for the lower half of the core. Each sediment slice was 

homogenized and analyzed.

Sediment subsamples and composited samples were 

analyzed for 55 major and trace elements at the USGSNRP laboratory. From the three San Juan cores, there were 

a total of 116 subsamples analyzed, including 15 laboratory 

replicates; also, 6 composited samples and 1 laboratory 

replicate composited sample were analyzed. From the three 

Escalante cores, a total of 75 subsamples were analyzed, 

including 14 laboratory replicates; also, 6 composited samples 

and 1 laboratory replicate composited sample were analyzed. 

In addition, 2 composited samples were analyzed from the 

Escalante Core 3 field replicate.

Composited samples also were analyzed for 55 low-level 

organochlorine pesticides and polychlorinated biphenyls (at the 

USGS National Water Quality Laboratory [NWQL]), 

61 polycyclic aromatic hydrocarbon compounds (at the 

NWQL), gross alpha and gross beta radionuclides (at Eberline 

Services through the NWQL), and sediment-particle size (at the 

USGS Cascades Volcano Observatory Laboratory).

Water samples were collected from the sediment-water 

interface overlying each of Cores 1–3 collected from the San 

Juan River and Escalante River deltas. Each water sample 

was analyzed for 57 major and trace elements at the USGSNRP laboratory.
Methods 5

Figure 3. Logs showing cores, core sections and lengths, subsample locations, and composited samples collected from the San Juan 

River and Escalante River deltas, Lake Powell, Utah.
6 Sediment and Water Chemistry of the San Juan River and Escalante River Deltas of Lake Powell, Utah, 2010–2011

Summary of Core and Water Analyses

Major and trace elements were detected at 

concentrations greater than reporting levels for most of the 

sediment subsamples and composited samples (appendixes 

A3–A5 for the San Juan and B3–B5 for the Escalante). For 

the San Juan, all elements were detected in each subsample 

except for rhenium, sulphur, selenium, and tellurium; and all 

elements were detected in each composited sample except for 

copper, rhenium, selenium, and tellurium. For the Escalante, 

all elements were detected in each subsample except for 

boron, bismuth, molybdenum, rhenium, sulphur, selenium, 

tin, tellurium, and zinc; and all elements were detected in 

each composited sample except for rhenium, selenium, and 

tellurium.

Low-level organochlorine pesticides and 

polychlorinated biphenyls were not detected in any of the 

sediment samples (appendixes A6–A7 for San Juan and 

B6–B7 for Escalante). Of the 61 PAH compounds analyzed, 

only 1 compound (p-Cresol) was detected at a concentration 

greater than the reporting level in only one sample—the San 

Juan Core 2, upper-half composited sample. Eighteen PAH 

compounds were detected in some San Juan samples and 

5 PAH compounds were detected in some Escalante samples, 

but all concentrations were less than reporting levels 

(appendixes A8–A9 for San Juan and B8–B9 for Escalante). 

Gross alpha and gross beta radioactivity concentrations 

were greater than reporting levels for all samples and ranged 

from 8 to 32 pCi/g for gross alpha radioactivity and from 

17.1 to 34 pCi/g for gross beta radioactivity (appendixes 

A10–A11 for San Juan and B10–B11 for Escalante). 

Sediment particle-size analyses showed that the core samples 

primarily consisted of fine (0.125 mm) and very fine 

(0.0625 mm) sands, silts, and clays (appendixes A12 for San 

Juan and B12 for Escalante).

For the water samples, most of the 57 major and trace 

elements analyzed were detected at concentrations greater 

than reporting levels (appendixes A13–A14 for San Juan and 

B13–B14 for Escalante). For the San Juan, however, cobalt, 

cesium, europium, nickel, and thorium were not detected in 

any of the samples and cadmium, phosphorus, and tin were 

not detected in 67 percent of the samples. For the Escalante, 

cobalt, chromium, phosphorus, and tin were not detected in 

any of the samples and tellurium was not detected in 

67 percent of the samples.

Results from all analyses are tabulated in appendix A for 

the San Juan River delta and appendix B for the Escalante 

River delta. The appendixes are Microsoft© Excel 2010 Excel 

workbooks with an extension of .xlsx and are available for 

download from the report Web page at http://pubs.usgs.gov/

of/2014/1096/. Both appendixes have the same structure and 

include 15 worksheets. Although some results are available 

in the USGS National Water Information System–Web 

Interface (NWIS-Web) database, not all results are suitable 

for storage in NWIS-Web. As such, this report and attached 

appendixes will be used to archive these data. 

Consideration for Future Studies

Lake Powell provides storage for water from three major 

rivers, the Colorado, the San Juan, and the Escalante Rivers, 

and more than 90 tributaries. The lake is used recreationally 

and provides habitat for many aquatic and terrestrial species. 

Glen Canyon NRA managers are concerned about the quality 

of water and deltaic sediment in the reservoir. This study 

expands a similar study done on the Colorado River delta 

in 2001. Additional studies could be done to further the 

existing work: (1) collect additional sediment cores from 

other large tributaries or areas of concern to Glen Canyon 

NRA to document the presence or absence of contaminants 

in sediment; (2) synthesize and document chemical analyses 

from all studies of the Colorado River, San Juan River, and 

Escalante River deltas; and (3) conduct additional chemical 

analyses on existing cores, such as age dating.

Summary

Lake Powell impounds three major rivers: the Colorado, 

San Juan, and Escalante. Sediment transported by these rivers 

form deltas in the inflow reaches to Lake Powell. Deltas 

are active areas of sediment deposition and erosion, and are 

potential sinks for contaminants. These contaminants may 

be released into the water as the deltas are reworked with 

changing lake levels, and may be harmful to humans and 

aquatic and terrestrial species. In 2010, the USGS began a 

sediment-core sampling and analysis program to assist Glen 

Canyon NRA managers, concerned about the quality of 

water and sediment in Lake Powell, document the presence 

or absence of contaminants in deltaic sediment from the two 

deltas that had not yet been studied, the San Juan River and 

Escalante River deltas.

Three sediment cores were collected from the San Juan 

River delta in the summer of 2010 and three sediment cores 

and one replicate core were collected from the Escalante 

River delta in the summer of 2011. Water samples also were 

collected from the sediment-water interface overlying each 

of the three cores from the San Juan River and Escalante 

River deltas. The cores were analyzed for 55 major and 

trace elements, 55 low-level organochlorine pesticides and 

polychlorinated biphenyls, 61 PAH compounds, gross alpha 

and gross beta radionuclides, and sediment-particle size. The 

water samples were analyzed for 57 major and trace elements.

Most of the major and trace elements analyzed were 

detected at concentrations greater than reporting levels for 

the sediment-core subsamples and composited samples. 

Low-level organochlorine pesticides and polychlorinated 

biphenyls were not detected in any of the samples. One PAH 

compound, p-Cresol, was detected at a concentration greater 

than the reporting level for one sample (San Juan Core 2, 

upper-half composited sample). Gross-alpha and gross-beta 

radionuclide concentrations were greater than reporting 
Appendixes 7

levels for all samples. The cores primarily consisted of fine 

sand, very fine sand, silts, and clays. Most of the major and 

trace elements analyzed were detected at concentrations 

greater than reporting levels for the water samples. Cobalt, 

cesium, europium, nickel, and thorium were not detected 

in water samples from the San Juan, and cobalt, chromium, 

phosphorus, and tin were not detected in water samples from 

the Escalante.

References Cited

Ferrari, R.L., 1988, 1986 Lake Powell Survey: Denver, 

Colorado, U.S. Bureau of Reclamation Technical Report 

REC-ERC-88-6, 67 p.

Hart, R.J., Taylor, H.E., Antweiler, R.C., Fisk, G.G., Anderson, 

G.M., Roth, D.A., Flynn, M.E., Peart, D.B., Truini, Margot, 

and Barber, L.B., 2004, Physical and chemical characteristics of Knowles, Forgotten, and Moqui Canyons, and effects 

of recreational use on water quality, Lake Powell, Arizona 

and Utah, U.S. Geological Survey Open-File Report 2004-

5120, 43 p.

Hart, R.J., Taylor, H.E., Antweiler, R.C., Graham, D.D., Fisk, 

G.G., Riggins, S.G., and Flynn, M.E., 2005, Sediment 

chemistry of the Colorado River delta of Lake Powell, Utah, 

2001: U.S. Geological Survey Open-File Report 2005-1178, 

33 p.

Potter, L.D., and Drake, C.L., 1989, Lake Powell: Virgin flow 

to dynamo: Albuquerque, University of New Mexico Press, 

311 p.

Pratson, L., Hughes-Clarke, J., Anderson, M., Gerber, T., 

Twichell, D., Ferrari, R., Nittrouer, C., Beaudoin, J., Granet, 

J., and Crockett, J., 2008, Timing and patterns of basin 

infilling as documented in Lake Powell during a drought: 

Geology, v. 36, no. 11, p. 843–846.

Vernieu, W.S., 1997, Effects of reservoir drawdown on 

resuspension of deltaic sediments in Lake Powell: Lake and 

Reservoir Management, v. 13, no. 1, p. 67–78.

Appendixes

Results from all analyses are tabulated in appendix A 

for the San Juan River delta and appendix B for the Escalante 

River delta. The appendixes are Microsoft© Excel 2010 Excel 

workbooks with an extension of .xlsx and are available for 

download from the report Web page at http://pubs.usgs.gov/

of/2014/1096/. 

Appendix A. Sediment Core Information and 

Sediment-Chemistry and Water-Sample Results 

for the San Juan River delta, Lake Powell, Utah, 

2010.

Appendix B. Sediment Core Information and 

Sediment-Chemistry and Water-Sample Results 

for the Escalante River delta, Lake Powell, Utah, 

2011.

Menlo Park Publishing Service Center, California

Manuscript approved for publication May 9, 2014

Edited by John Buursma

Design and layout by Cory Hurd
Hornewer—Sediment and Water Chemistry of the San Juan River and Escalante River Deltas of Lake Powell, Utah, 2010–2011—Open-File Report 2014–1096

http://dx.doi.org/10.3133/ofr20141096

ISSN 2331-1258 (online)