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The U.S. Geological Survey (USGS), which was established in 1879, provides
earth-science information to aid in the understanding, development,
management, and protection of the Nation's land, water, mineral,
biological, and energy resources. The results of that work-maps, reports,
data, and other information-are used every day by persons at all levels of
government, universities, research institutions, industries, businesses,
and individual citizens and citizen groups.
The USGS works in all 50 States, frequently in cooperation with others.
This Fact Sheet describes some of the current USGS programs in
Tennessee. |
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The USGS, in cooperation with numerous Federal, State, and local agencies,
collects hydrologic data to meet the needs of many users. These data
document present conditions and provide the cornerstone for understanding
hydrologic systems and solving hydrologic problems. In Tennessee, the USGS
records streamflow continuously at 121 gaging stations equipped with
recorders and makes instantaneous measurements of streamflow at numerous
other stations (fig. 1). Ground-water levels are monitored statewide, and
the physical, chemical, and biological characteristics of surface and
ground waters are analyzed. Records of water use are compiled and updated
and data for the national baseline network, water-quality network, and
atmospheric-deposition programs are provided.
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Figure 1. USGS field crew prepares to measure streamflow of a Tennessee
river. | |
The data are used for many purposes. For example, satellite-transmitted
data that describe present river conditions are used to manage and operate
the reservoir systems on the Tennessee and the Cumberland Rivers, to
respond quickly to floods, and for certain cities and towns along the
rivers, to determine permissible windows of time for waste disposal. The
longer term record of data-going back in time for more than 100 years-is
used for various engineering purposes and to manage river flood-plain
development, to determine flood-insurance rates, to determine trends in
water availability and quality, to project and plan for future water
demand, and to conduct interpretive studies of water-related problems that
may benefit many thousands of people. |
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The Minerals Resource Data System (MRDS), which is a digital data base that
lists all known mineral sites worldwide, has been developed by the USGS, in
cooperation with many agencies, to provide up-to-date information on
mineral occurrences and related data. The MRDS supports USGS research and
mineral-resource assessments and is a principal tool for providing
mineral-related information to Federal and State agencies, industry, and
the public. The data base contains information on more than 110,000 sites;
almost 1,650 of them are in Tennessee. |
The USGS, in cooperation with the Tennessee Division of Geology, has
prepared mineral records for Tennessee. Most of the Tennessee data
describe occurrences of barium, iron, zinc, sand and gravel, and phosphate.
Work currently is in progress to transfer information in the MRDS to a
CD-ROM. |
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Maps and digital cartographic data have innumerable applications, and the
requirements for this information are expanding dramatically. The National
Mapping Program, which is conducted in cooperation with numerous State and
Federal agencies, strives to ensure that map data in graphic and digital
forms are available to the public through timely and effective
data-collection and revision procedures. |
The 1:24,000-scale topographic maps (1 inch on the map represents 2,000
feet on the ground) are among the most popular and versatile products of
the USGS. These maps are widely used by scientists and engineers and have
long been favorites with the general public for recreational purposes. In
addition to showing topography, they depict the natural and cultural
features of the landscape, such as lakes and streams, highways and
railroads, boundaries, and geographic names. Tennessee is covered by 803
maps at this scale. Digital coverages for boundary, hydrography, and
transportation features are available for about 25 percent of these maps,
and digital elevation model coverages are available for about 90 percent. |
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The USGS, in cooperation with the National Park Service, is conducting
field studies in the Great Smoky Mountains National Park to provide
geologic map data that will be used to help manage the Nation's most
heavily visited National Park. Study results are being compiled in digital
files that can be accessed by computers that have geographic information
system (GIS) software. GIS provides an efficient method for storing and
manipulating large amounts of data for this 520,004-acre park.
Additionally, geologic maps for 368 7.5-minute quadrangles, mostly for
middle Tennessee, have been converted to GIS coverages; these coverages can
be widely used for local and regional studies and for management purposes.
The coverages were made by the USGS in cooperation with the Tennessee
Department of Environment and Conservation, the U.S. Army Corps of
Engineers, the Tennessee Valley Authority, and the Natural Resources
Conservation Service (formerly the Soil Conservation Service). |
As part of the National Geologic Mapping Program, the USGS, in cooperation
with the Tennessee Division of Geology, is mapping the geology of the
Greenville, the Johnson City, and the Bristol 7.5-minute quadrangles in the
northeastern part of the State. Parts of these areas are underlain by
limestone in which solution cavities have developed. One of the objectives
of mapping is to provide geologic information that addresses regional
concerns about the transport of hazardous substances from Superfund sites
in ground water that flows through cavernous limestone. |
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Economic growth and development in Tennessee depend on the availability of
local sources of minerals and materials used in construction, industry, and
manufacturing and for maintaining and upgrading the State's infrastructure.
In 1993, the USGS published an inventory of known mineral resources in the
8,027-square-mile area of the Chattanooga 1° by 2° quadrangle in
southeastern Tennessee and maps that show potential areas for undiscovered
deposits. Five tracts that are favorable for the occurrence of mineral
resources, including metals, industrial minerals, and fuels were
delineated. Construction and industrial materials, especially limestone,
dolomite, sand, and gravel, were shown to have the greatest potential for
increased development to meet current needs and the requirements of future
population growth, industrial expansion, and new markets. The report and
maps are being used by Federal and State land-management agencies, land-use
planners, industry, and local governments to help ensure that adequate
supplies of these minerals remain available and to promote resource
development at the lowest possible cost. |
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A prototype quantitative national assessment of mineral resources is being
completed for five commonly used metals-gold, silver, copper, lead, and
zinc. Objectives of this effort are to list significant known deposits, to
identify areas with mineral potential, and to estimate the quantity of each
metal that is likely to be present. Although Tennessee does not have known
economically important deposits of gold, silver, or copper, the State does
have geologic terrains that are favorable for hosting zinc and lead
deposits. Tracts that have known deposits and potential for deposits are
outlined on maps on the basis of information in the MRDS and on geologic
maps. The national assessment will enable the USGS to respond quickly to
requests for information from Congress, Federal and State agencies,
industry, and the public about mineral resources throughout the country.
The results also will be useful to land-use planners who are concerned with
resource-management issues. |
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The USGS is conducting a National Coal Assessment (NCA). Coal is an
important energy source, which accounts for about 25 percent of the total
energy used and about 56 percent of the electricity generated in the United
States. In 1995, about 2.7 million of the 1.02 billion tons of coal
produced nationally were mined in Tennessee. It is expected that coal will
continue to serve as a major energy source as the Nation enters the next
century, and that the quality requirements for this material will become
even more stringent as new technologies that use coal come on line.
Objectives of the NCA are to provide details on the location, quantity, and
quality of coal that can be mined throughout the country during the next 20
years, classified by best intended use. |
In a related study, the USGS, in cooperation with the Tennessee Division of
Geology, is systematically revising, one quadrangle at a time, coal-reserve
maps and reserve estimates for selected areas in the Tennessee coal field.
Data are being entered in the National Coal Resources Data System. The
ultimate goal is to publish an up-to-date coal-reserve estimate for
Tennessee's 20 coal-bearing counties that can be periodically revised and
updated as needed. |
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The largest earthquakes known to have occurred within the interior of the
United States struck the central Mississippi River Valley during winter
1811-12. They were centered in the New Madrid, Missouri, region and were
felt as far away as Quebec. This region continues to have the highest
level of seismicity east of the Rocky Mountains. Two critical needs for
determining regional earthquake hazards are the development of an accurate
chronology of past large earthquakes and the location of buried faults
along which past movement has occurred.
A team of USGS research geologists stationed at the University of Memphis
is investigating prehistoric movement along the Reelfoot Fault near
Tiptonville (fig. 2). The scarp caused by this Fault forms the western
shore of Reelfoot Lake, which was created by the great New Madrid
earthquakes. The team's trenching studies have confirmed earlier work by
the USGS that suggested that two strong earthquakes occurred within a
2,000-year period before 1811. The most recent data indicate that the
dates of the earthquakes are about 900 and 1400. These dates are
consistent with evidence for those of past earthquakes found by other
researchers working in nearby Arkansas and Missouri. |
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Figure 2. Locations of earthquake research studies.
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As part of the National Earthquake Hazards Reduction Program, the USGS, in
cooperation with the Tennessee Division of Geology and Vanderbilt
University, is conducting gravity surveys in Lauderdale and Tipton
Counties. The information that results from this work will enable
scientists to locate buried faults and other geologic features associated
with earthquakes more precisely and will improve the ability to predict
which areas are most likely to sustain significant damage by a major
seismic event. |
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The USGS, in cooperation with the U.S. Air Force, the U.S. Navy, and the
U.S. Army, is conducting hydrogeologic investigations at three military
bases in Tennessee.
The purpose of the investigations is to provide resource managers with the
geologic and hydrologic information necessary to protect water quality at
each facility. |
A study at Arnold Air Force Base has provided an overview of the regional
hydrology and a computer model that simulates the ground-water flow system.
A detailed study is being made of an area where continual pumpage of a
250-foot-deep cylindrical excavation, which is used for testing rocket
motors, has dewatered aquifers and induced the transport of contaminants
through them. An investigation at the Naval Air Station in Memphis has
defined the stratigraphy that underlies the northern part of the base to a
depth of about 1,000 feet and summarized the hydrogeologic character of
each formation. Similar work is continuing for the southern part of the
base. The primary objective of a recently started study at Fort Campbell
is to provide information on the occurrence and movement of ground water at
the base and adjacent counties in Tennessee and Kentucky. One of the goals
is to delineate the recharge area of Boiling Spring, which supplies about 6
million gallons of water per day and is the principal source of drinking
water for the base, so that protective measures may be implemented. |
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Agricultural activities are a major contributor to nonpoint-source
pollution; that is, pollution that cannot be traced to a single point of
origin. In Tennessee, agriculture has been cited as one of the five
leading causes of water impairment. Attempts have been made to reduce the
extent of impairment in some areas by implementing conservation-related
measures termed "best-management practices" (BMP's).
The USGS is conducting a study to evaluate the effect of agricultural
activities on water quality and the effectiveness of agricultural BMP's in
the 95,000-acre Beaver Creek watershed of West Tennessee. The project is
being conducted jointly with other Federal, State, and county agencies, the
farming community, and academic institutions in support of the U.S.
Department of Agriculture's Hydrologic Unit Area Program. |
Sediment transport that results from soil erosion has been determined to be
the major water-quality problem in the watershed. Some other significant
findings are that higher nitrate concentrations are measured in water from
wells near septic tanks and confined animal facilities than in wells near
fertilized fields, and wells deeper than about 150 feet do not appear to be
as affected by surface or near-surface nitrate sources as those of
shallower depth. The horizontal transport of aldicarb sulfoxide, which is
a metabolite (daughter product) of the pesticide aldicarb, was negligible,
and the downward transport was minimal, with none being detected below a
depth of 2.5 feet. Nonbiological reactions appear to be important
mechanisms for the rapid degradation of aldicarb metabolites in the soil
profile. The findings will be useful for evaluating and improving the
BMP's, reducing soil loss from this very fertile area, and improving the
quality of water in wells and streams. |
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The USGS, in cooperation with the Tennessee Department of Agriculture,
recently began a study to determine the causes of water-quality impairment
in the North Fork Creek and the Fall Creek watersheds in Bedford County,
Middle Tennessee. Water quality is impaired by fecal contamination that
has resulted in algal growths in the streams and a decline in the quality
of drinking-water supplies. The watersheds are situated on karst
(limestone) terrain, which is characterized by sinkholes, caves and
conduit-type ground-water flow. As is typical of many karst terranes,
water in streams and below ground readily interchange.
Preliminary results after 1 year of study show that nitrate-nitrogen in 90
samples of stream water approached but did not exceed the Tennessee
standard for drinking water; the number of fecal bacteria colonies in 14 of
16 samples of stream water exceeded the Tennessee standard for recreational
water use; samples from 4 of 7 streams tested positive for laundry
brighteners, thus suggesting that septic tank outflow may contribute to the
problem; and initial tests at the University of Memphis indicate that the
ribonucleic acid (genetic material) of fecal bacteria has excellent
potential for defining whether the bacteria are of human or animal origin,
and if of animal origin, which group of animals. |
Results of the study will help managers make decisions to improve the
quality of water in not only the two watersheds, but also in the receiving
stream, the Duck River, which is the source of water for many communities.
Additionally, if the use of ribonucleic acid proves successful for
identifying the source of fecal contaminants, then the results will be
applicable to similar contamination problems worldwide. |
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The National Water-Quality Assessment (NAWQA) Program was established to
describe the status and trends in the quality of a large, representative
part of the Nation's surface and ground waters and to identify the natural
and human factors that affect the quality of these resources. Information
produced will be used by policymakers and managers at local, State, and
national levels for making decisions and managing the quality of much of
the water resources of this country.
The national assessment will consist of 60 study units that encompass parts
of most major river basins and aquifer systems in the Nation. Three of the
study units include regions in Tennessee-the upper Tennessee River Basin,
the lower Tennessee River Basin, and the Mississippi Embayment (fig. 3).
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Figure 3. National Water-Quality Assessment Program study units that
include Tennessee. | |
Water-quality assessment activities in the upper Tennessee River Basin and
the Mississippi Embayment study units began in 1994. Meetings with public
and private agencies resulted in an identification and prioritization of
several water-quality issues of regional and local interest, a
determination of sources of water-quality data and other information, and
assistance in the design and scope of project elements. In the upper
Tennessee River Basin study unit, most of the water-quality constituents of
greatest concern are sediment related. Nutrient enrichment from
agricultural activities also is a concern to environmental agencies. In
the Mississippi Embayment study unit, the issues of greatest concern are
the impacts of agricultural land use and agricultural chemicals on water
quality. For the Metropolitan Memphis area, the effects of residential
land use on water quality is a major issue. Although study of the lower
Tennessee River Basin study unit is not scheduled to start until 1997,
preliminary inquiry of Federal, State, and local agencies has ascertained
that sedimentation, nutrient enrichment, and habitat degradation of surface
water and bacterial contamination of ground water are the issues of
greatest regional importance. |
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The Earth Science Information Centers (ESIC's) provide information about
USGS programs, products, and technological developments to the public. The
ESIC in Knoxville was established under a cooperative agreement between the
USGS and the University of Tennessee's Cartographic Information Center.
The ESIC in Chattanooga is operated by the Tennessee Valley Authority. As
part of the national ESIC network, these offices provide information on
such earth science topics as cartography, geography, digital data, remote
sensing, geology, geophysics, geochemistry, hydrology, geohydrology, aerial
photography, and land use. The Chattanooga ESIC also sells maps that cover
many Southeastern States. The ESIC's are supported by the USGS with
reference materials, technical assistance, training and outreach
activities, and access to USGS data bases. |
FS-042-96.pdf 165K