U.S. Department of the Interior

U.S. Geological Survey

USGS Fact Sheet 052-99

January 2000

Wyoming

Wyoming’s social and economic

development is driven, in large part

by its natural resources. For more

than 100 years, the U.S. Geological

Survey (USGS) has been involved in

studies of the geology, geography,

water resources, and, more recently,

the biological resources of Wyoming.

Results of these studies provide

natural-resource managers and

policymakers with essential earth

science information needed to make

decisions about the use and conservation of Wyoming’s resources.

Integrated Geoscience Studies of

the Greater Yellowstone Area

Integrated geoscience studies conducted by the USGS provide information that can be applied to the stewardship of the natural resources of

Yellowstone National Park (YNP)

and the Greater Yellowstone Area

(GYA) (fig. 1). The studies include

investigations of hydrothermal

systems in relation to magmatic

activity, caldera development, active

faulting, fluid flow, ore-forming

processes, and impacts on wildlife,

plants, and climate. Additional studies

include:

• using geophysics to understand the

“plumbing” system of the Yellowstone caldera, geothermal systems,

and to help locate active faults,

• surveying the bottom of the

northern part of Yellowstone Lake

to complement ongoing studies of

active hydrothermal vents and

explosion craters;

• mapping surficial mineralogy and

vegetation communities to show

the distribution of white pine,

which will be used to define bear

habitat,

• establishing a geochemical database to help evaluate the environmental health of YNP, including its

wildlife, through time.

Geologic mapping is intended to

provide information about geologic

influences on environments of

particular plant and animal species.

Life cycles of some plants and the

animals that eat the plants are affected by circulating hydrothermal

water enriched with trace elements.

The role of the USGS in the GYA, in

cooperation with local, State, and

Federal agencies, is to transfer and

apply USGS technology, and to

distribute information to the scientific

community, citizens, public interest

groups, and the media. Exhibits

planned by the National Park Service

(NPS) may include information from

USGS studies and demonstrate the

relevance of earth science to the

stewardship of Federal lands.

The USGS is producing digital

geologic maps (1:100,000 scale) for

the GYA, as part of the National

Geologic Map database This activity

is an initiative under the Greater

Yellowstone Ecosystem program of

the USGS, a cooperative program

with the NPS, U.S. Forest Service,

and other local, county, and State

agencies in Wyoming, Montana, and

Idaho. The digital geologic maps will

be combined with other spatial

databases for studies of wildlife

habitat, geologic hazards, and the

geochemical effects that different

rock types have on water, plants, and

animals in the area.

The USGS also has constructed

digital orthophoto quadrangles

(DOQ’s) and digital elevation models

(DEM’s) for parts of the GYA (fig. 2).

DOQ’s are scanned aerial photographs for 7.5-minute quadrangles

(scale 1: 24,000) in which distortion

and displacements caused by the

camera orientation and terrain are

removed. DEM’s are digital files of

terrain elevations for ground positions

at regularly spaced horizontal intervals. Ongoing work provides basemap data for the GYA in Wyoming,

Montana, and Idaho. The data are

Figure 1. Public lands in the Greater

Yellowstone area.

National Forest

EXPLANATION

National Park

Indian Reservation

National Wildlife Refuge

Bureau of Land Management

MONTANA

WYOMING

IDAHO

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Bozeman

Dillon

Billings

Cody Yellowstone

 National

 Park

Ashton

Pocatello

Idaho

Falls

Riverton

Lander
science for a changing world

intended to be used for studying

population demographics, estimating

visitor and recreation demands,

studying the effects of human and

animal interactions, identifying

geothermal hazards, studying noxious

weeds and land use, and protecting

natural resources.

Cartographic and Geographic

Data

Through several programs the USGS

produces and publishes basic cartographic and geographic data for

Wyoming. Much of the work is in

cooperation with other agencies. In

one highly successful program, the

Wyoming State Engineers Office,

Wyoming Water Development

Commission, State Lands Office,

cities and counties, the Bureau of

Reclamation, and the U.S. Department of Agriculture provide cooperative funding for producing

DOQ’s. Because DOQ’s are referenced to ground control, the images

may be loaded into a geographic

information system (GIS) and used

with other data for analysis. Of the

1,922 quadrangles for Wyoming,

only about 300 remain to be mapped

as DOQ’s.

Other activities include the establishment of State data-sharing clearinghouses, with the help of the Federal

Geographic Data Committee; the

clearinghouses are components of the

National Spatial Data Infrastructure.

Also, the Wyoming Natural Resources Data Clearinghouse of the

University of Wyoming, the Greater

Yellowstone Area Data Clearinghouse, and the Wyoming Spatial Data

Clearinghouse of the State Office of

GIS are partners with the USGS in

making geospatial data accessible to

the public. In addition to data coordination and sharing roles, the USGS is

involved in the Wyoming Geographic

Information Advisory Council, which

provides leadership and establishes

GIS policy for the State of Wyoming.

Yellowstone River Basin National

Water-Quality Assessment

The USGS is studying water quality

in the Yellowstone River Basin in

Wyoming, Montana, and North

Dakota as part of the National Water

Quality Assessment Program

(NAWQA). Water-resource managers

need, but commonly lack, sufficient

information for making effective

management decisions and for

evaluating long-term changes in water

quality. Changes in water quality can

affect an entire ecosystem, raising

concerns about drinking-water

quality, habitat degradation or destruction, and loss of use of the water.

The Yellowstone River Basin

NAWQA will provide needed information about surface- and groundwater quality and the factors that

influence water quality in the basin.

Water-quality issues in the Yellowstone River Basin range from potential degradation of pristine streams in

headwater areas to industrial and

agricultural effects in downstream

reaches. Specific issues include:

• trace elements (for example,

selenium and arsenic) originating

from sources such as leachate from

mine spoils, leaching of soil, water

from geothermal areas, and

uranium-rich rocks;

• toxic compounds from leachate,

pesticides, hydrocarbons, and

industrial and commercial waste;

• increasing salinity in ground and

surface water;

• sediment problems in streams;

• effects of dewatering of aquifers;

• nutrient enrichment of ground and

surface water from fertilizer

application and from animal and

human waste; and

• water quality on tribal lands.

Pesticide Monitoring of Ground

Water

The USGS is conducting a pesticidemonitoring program, in cooperation

with the Wyoming Department of

Agriculture (WDA), in selected

agricultural areas (potentially in all

23 counties) to determine the extent

of pesticides in ground water. The

WDA is implementing the State’s

generic Management Plan for Pesticides in Ground Water, in cooperation with other State and Federal

agencies, for the U.S. Environmental

Protection Agency. Increased pesticide use has raised concerns about the

effects of pesticides on the environment and human health. Ground

water, the sole source of drinking

water for rural residents in many parts

of Wyoming, is particularly susceptible to contamination.

Initial sampling by the USGS has

been completed in Goshen, Park, and

Washakie Counties and is underway

in Laramie, Lincoln, and Fremont

Counties. The sampling strategy was

based on the potential vulnerability

of ground water to pesticide contamination shown on maps created

Figure 2. Part of digital orthophoto

quadrangle of the Old Faithful area in

Yellowstone National Park.
Wyoming

by the University of Wyoming Spatial

Data and Visualization Center (fig.

3). Eighteen pesticides and two

degradation products were chosen for

analysis.

Shallow alluvial and terrace aquifers

typically were identified as the

aquifers most vulnerable to pesticide

contamination. Concentrations of all

pesticides detected in water from

wells in Goshen, Park, and Washakie

Counties were less than the safe

drinking-water standard or its equivalent established by the Wyoming

Department of Environmental Quality

for municipal supplies. These standards do not apply to private domestic well water, but the standards

provide a reference to the acceptable

amount of chemicals in drinking

water. Atrazine was the most commonly detected pesticide. Trace

amounts of atrazine were found in

more than one-half of the water

samples from the three counties in

which the pesticide was detected.

Basic Hydrologic Data

The USGS, in cooperation with many

local, State, and Federal agencies,

collects hydrologic data at surfacewater and ground-water sites throughout Wyoming. Depending upon the

information needed, the data are

collected continuously with automatic

recording devices, intermittently, or

by a single sample or measurement

(fig. 4). Since 1888, streamflow data

have been collected at more than

2,000 sites, and surface-water-quality

data at more than 1,600 sites.

About 150 streamflow stations are

operating (1999). All USGS data are

available to the public; streamflow

data from many stations are available

in near-realtime on the World Wide

Web. The hydrologic-data program is

the foundation upon which most other

water-resources investigations are

based.

Although the USGS has no management or regulatory function, the

short-term and long-term data acquired through this program have

many uses. Local, State, and Federal

agencies use the data for daily and

annual management of Wyoming

water, including allocation of water

under State and Federal laws, enforcement of water-quality standards,

and design of highway bridges and

culverts. Also, the data are used for

hydrologic investigations including:

• developing improved data-collection methods,

• describing and appraising water

resources,

• determining the extent and severity

of droughts,

• documenting floods and developing methods for estimating the

magnitude of floods of a given

frequency, and

• assessing the effects of human

activities on surface-water and

groundwater resources.

Invasive Weeds

To determine the impacts of invasive,

nonnative plants on native plant

communities in forest, grassland, and

wetland habitats, USGS scientists are

working in cooperation with the NPS,

Bureau of Land Management (BLM)

and Colorado State University. New

sampling techniques are helping

researchers pinpoint “hot spots” for

exotic species and predict new areas

of invasion. Habitats with the highest

numbers of native species, including

wetlands and streamside zones, are

particularly vulnerable to nonnative

weeds. In such areas, the invaders

often spread at the expense of unique

or narrowly distributed native species. Information gained in these

studies is intended to help scientists

propose cost-effective strategies for

nonnative weed eradication and

native habitat restoration.

Big Game Use of Reclaimed

Mining Lands

Researchers at the USGS Wyoming

Cooperative Fish and Wildlife

Research Unit in Laramie compared

Figure 3. Locations of wells where

water was sampled for pesticides,

and the potential vulnerability of

ground water to pesticide

contamination in Washakie County.

EXPLANATION

Vulnerability to pesticide

contamination

 High

 Medium high

 Medium

 Medium low

 Low

 Not included in vulnerability estimates

Worland

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5

0

0

WYOMING

Washakie

County

Map area

Pesticide not detected

 in well

Pesticide detected in well

Figure 4. A USGS hydrographer

measuring streamflow. Photo courtesy

of the Wyoming Tribune-Eagle.
Printed on recycled paper

USGS office locations USGS State Representative

2617 E. Lincolnway

Suite B

Cheyenne WY 82001-5562

(307) 778-2931

FAX (307) 778-2764

USGS Home Page

http://www.usgs.gov/

Reports and products

1-888-ASK-USGS

The USGS has 49

employees in Wyoming

Casper

Jackson

Riverton

Cheyenne

Laramie

big game animals’ use of native

habitats and reclaimed mining lands.

The results of this study are intended

to help mining companies and

government agencies design and

implement reclamation projects in

ways most favorable to big game.

Pronghorn antelope, mule deer, and

elk each showed distinct habitat

preferences and distribution patterns,

but all three used reclaimed areas

during all or part of the year (fig. 5).

Particular features of the vegetation

on reclaimed lands were associated

with greater use by different game

species. Pronghorn, for example,

preferred reclaimed sites on which

alfalfa was present. Mule deer made

consistent use of reclaimed grasslands, but elk used those areas only

during late fall and winter.

Energy-Resource Assessment

USGS scientists, in cooperation with

the Wyoming State Geological

Survey, BLM, Office of Surface

Mining, and coal-mine operators, are

assessing the availability, quantity,

and quality of the coal, oil and gas,

and coalbed methane in the State

(fig. 6). One major objective is to

generate, store, and manipulate the

data in digital format so that it will be

available for analysis by using a GIS.

The digital database will provide

information to potential users in a

readily available format.

The coal-resource assessment

includes gathering information about

geography, stratigraphy, geochemistry, and quality of coal zones and

beds in the State. Potentially minable

coals included in the assessment are

associated with the 55–65-millionyear-old Fort Union Formation. The

USGS has examined deposits in the

Powder River, Hanna, Carbon, and

Green River Basins. Mining of these

coal resources, especially those in the

Powder River Basin, contributes

substantially to the State’s economy

through increased jobs and severance

taxes.

Oil-and-gas resources in Wyoming

are being assessed by the USGS as

part of a national study of 18 priority

provinces in the United States that are

estimated to contain 90–95 percent of

the Nation’s known and undiscovered

natural-gas resources. Provinces in

Wyoming include the Greater Green

River Basin and the Wyoming Thrust

Belt. The study integrates all of the

elements of the petroleum geology of

a basin, including source-rock

characterization, hydrocarbon migration, timing of migration and structural evolution, sequence stratigraphy, and reservoir quality.

Coalbed methane in the Powder

River Basin is undergoing substantial

development. The methane has been

estimated to be as much as 39 trillion

Figure 5. Elk grazing on reclaimed

mining land.

cubic feet. Resource managers need

accurate basinwide and local gasresource estimates and content

analyses. For this assessment, USGS

scientists are using data on coal

geology, stratigraphy, and the reservoir to develop models of the basin.

Chemical analyses and density

measurements will be performed on

coal cores collected from coalbed

methane wells throughout the basin.

Figure 6. Energy-resource areas.

Fort Union Formation (in some

 areas includes equivalent units

 or adjacent Wasatch units)

EXPLANATION

Subsurface

Surface

Major structural basins

Powder River

Greater Green River

Bighorn

Wind River

WYOMING

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2

3

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1

2

3

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1