USGS Science⌕ Search

SEARCH · USGS Science

Results for “Natural Resources Report”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,729 records · Page 96Linked to original sources

Hydrogeology and water-supply potential of the water-table aquifer on Dauphin Island, Alabama

The water table aquifer on Dauphin Island, Alabama, consists of a thin veneer of Holocene sand and an underlying Pleistocene unit locally known as the Gulfport Formation. The aquifer is from 28 to 35 ft thick with a thick marine clay at its base. Water in the aquifer generally is low in chloride content except near the coast. Excessively high iron concentrations in groundwater were found locally. A two-dimensional finite-difference groundwater flow model of the water table aquifer on Dauphin Island was used in the steady-state mode to evaluate the flow system under steady-state conditions. Model input data were obtained primarily from 40 test wells, 2 aquifer tests, continuous recording of groundwater levels, and rainfall. The model was calibrated to the low water-table conditions of July 1985 and high water table conditions of April 1985. The model was also used to simulate pumpage from the aquifer under transient conditions with no rainfall. Patterns of computed head changes compared favorably to the natural recession of water levels for the periods of April to May 1985 and May to June 1985. Simulation of groundwater withdrawals in the transient model showed the feasibility of producing 0.6 million gallons/day from eight wells that tap the water table aquifer without inducing lateral seawater encroachment. (USGS)

Water-Resources Investigations Report↗

Hydrology and quality of ground water in northern Thurston County, Washington

Northern Thurston County is underlain by as much as 1,800 feet of unconsolidated deposits of Pleistocene Age that are of glacial and nonglacial origin. Iterpretation of approximately 1,140 drillers' logs led to the delineation of seven major geohydrologic units, four of which are significant aquifers. Precipitation ranges from about 35 to 65 inches per year across the study area. Estimates of recharge indicate that the ground-water system of the Ground Water Management Area (GWMA), a subset of the study area, receives an average of about 28 inches per year. Ground water generally moves toward marine water bodies and to major surface drainage channels. At least 33,000 acre-feet per year of ground water discharges as springs from the GWMA. Approximately 21,000 acre-feet of water was withdrawn from the ground-water system of the GWMA through wells in 1988. Total ground-water use in the GWMA in 1988 was approximately 37,000 acre-feet. About 16,000 acre-feet of water that discharges naturally through springs was used together with water withdrawn by wells for domestic supply, agricultural, commercial, industrial, institutional, and aquaculture and livestock uses. Generally, the chemical quality of the ground water was good and 94 percent of the water samples were classified as soft or moderately hard. Of the few water-quality problems encountered, the most widespread anthropogenic problem appeared to be seawater intrusion. However, a comparison with data from 1978 indicated that the degree and extent of intrusion had not changed significantly since that time. Agricultural activities may be responsible for the presence of nitrate in ground waters at some individual wells, but septic tanks in areas of high housing density are likely responsible for elevated nitrate concentrations near the Cities of Lacey and Tumwater. The close correlation of nitrate concentrations with detergent concentrations supports the theory that the nitrate originates in septic systems, the only likely source of the detergents. Most water-quality problems in the study area, however, are due to natural causes. Iron concentrations are as large as 21,000 micrograms per liter, manganese concentrations are as large as 3,400 micrograms per liter, and connate seawater is present in ground water in the southern part of the study area.

Washington↗

Particulate, colloidal, and dissolved-phase associations of plutonium and americium in a water sample from well 1587 at the Rocky Flats Plant, Colorado

In November 1991, the initial phase of a study to determine the dominant aqueous phases that control the transport of plutonium (Pu), americium (Am), and uranium (U) in surface and groundwater at the Rocky Flats Plant was undertaken by the U.S. Geological Survey. By use of the techniques of stirred-cell spiral-flow filtration and crossflow ultrafiltration, particles of three size fractions were collected from a 60-liter sample of water from well 1587 at the Rocky Flats Plant. These samples and corresponding filtrate samples were analyzed for Pu and Am. As calculated from the analysis of filtrates, 65 percent of Pu 239 and 240 activity in the sample was associated with particulate and largest colloidal size fractions. Particulate (22 percent) and colloidal (43 percent) fractions were determined to have significant activities in relation to whole-water Pu activity. Am and Pu 238 activities were too low to be analyzed. Examination and analyses of the particulate and colloidal phases indicated the presence of mineral species (iron oxyhydroxides and clay minerals) and natural organic matter that can facilitate the transport of actinides in ground water. High concentrations of the transition metals copper and zinc in the smallest colloid fractions strongly indicate a potential for organic complexation of metals, and potentially of actinides, in this size fraction.

Colorado↗

Hydrogeology of the Pictured Cliffs Sandstone in the San Juan structural basin, New Mexico, Colorado, Arizona, and Utah

This report is one in a series resulting from the U.S. Geological Survey's Regional Aquifer System Analysis (RASA) study of the San Juan structural basin that began in October 1984. The purposes of the study (Welder, 1986) are to: (1) Define and evaluate the aquifer system; (2) assess the effects of past, present, and potential ground-water use on aquifers and streams, and (3) determine the availability and quality of ground water. Previous reports in this series describe the hydrogeology of the Dakota Sandstone (Craigg and others, 1989), Gallup Sandstone (Kernodle and others, 1989), Morrison Formation (Dam and others, 1990), Point Lookout Sandstone (Craigg and others, 1990), Kirtland Shale and Fruitland Formation (Kernodle and others, 1990), Menefee Formation (Levings and others, 1990), Cliff House Sandstone (Thorn and others, 1990), and Ojo Alamo Sandstone (Thorn and others, 1990) in the San Juan structural basin. This report summarizes information on the geology and the occurrence and quality of water in the Pictured Cliffs Sandstone, one of the primary water-bearing units in the regional aquifer system. Data used in this report were collected during the RASA study or derived from existing records in the U.S. Geological Survey's computerized National Water Information System (NWIS) data base, the Petroleum Information Corporation's data base, and the Dwight's ENERGYDATA Inc. BRIN database. Although all data available for the Pictured Cliffs Sandstone were considered in formulating the discussions in the text, not all those data could be plotted on the illustrations. The San Juan structural basin in New Mexico, Colorado, Arizona, and Utah has an area of about 21,600 square miles (fig. 1). The structural basin is about 140 miles wide and about 200 miles long. The study area is that part of the structural basin that contains rocks of Triassic and younger age; therefore, the study area is less extensive than the structural basin. Triassic through Tertiary sedimentary rocks are emphasized in this study because these units are the major aquifers in the basin. The study area is about 140 miles wide (about the same as the structural basin), 180 miles long, and has an area of about 19,400 square miles. Altitudes in the study area range from about 4,500 feet in southeastern Utah, to about 11,000 feet in the southeastern part of the basin. The area-weighted mean altitude is about 6,700 feet. Annual precipitation in the high mountainous areas along the north and east margins of the basin is as much as 45 inches, whereas annual precipitation in the lower altitude, central basin is generally less than 8 inches. Mean annual precipitation is about 12 inches. Data obtained from documents published by the U.S. Bureau of the Census (1980 and 1985) were used to calculate the population of the study area. The population in 1970 was calculated to be about 134,000. The population increased to about 194,000 in 1980,212,000 in 1982,221,000 in 1984, and then declined to about 210,000 in 1985. The economy of the basin is supported by exploration and development of natural gas, petroleum, coal, and uranium resources; urban enterprise; farming and ranching tourism, and recreation. The rise and fall in population were related to changes in the economic strength of the minerals, oil, and gas industries, and support services. Uranium-mining and -milling activities underwent rapid growth until the late 1970's when most uranium-mining activity came to an abrupt end. Likewise, the oil and gas industry prospered until about 1983 and then declined rapidly.

Hydrologic Atlas↗

Scientific monitoring plan in support of the selected alternative of the Glen Canyon Dam Long-Term Experimental and Management Plan

Introduction The purpose of this document is to describe a strategy by which monitoring and research data in the natural and social sciences will be collected, analyzed, and provided to the U.S. Department of the Interior (DOI), its bureaus, and to the Glen Canyon Dam Adaptive Management Program (GCDAMP) in support of implementation of the Glen Canyon Dam Long-Term Experimental and Management Plan (LTEMP) (U.S. Department of the Interior, 2016a). The selected alternative identified in the LTEMP Record of Decision (ROD) (U.S. Department of the Interior, 2016b) describes various data collection, analysis, modeling, and interpretation efforts to be conducted by the U.S. Geological Survey’s (USGS) Grand Canyon Monitoring and Research Center (GCMRC), partner agencies, and cooperators that will inform decisions about operations of Glen Canyon Dam and management of downstream resources between 2017 and 2037, the performance period of the LTEMP. General data collection, analysis, modeling, and interpretation activities are described in this science plan, whereas specific monitoring and research activities and detailed study plans are to be described in the GCDAMP’s triennial work plans (TWPs) to be developed by the Bureau of Reclamation and GCMRC with input from partner agencies and cooperators during the LTEMP period, which are to be reviewed and recommended by the GCDAMP and approved by the Secretary of the Interior. The GCDAMP consists of several components, the primary committee being the Adaptive Management Work Group (AMWG). This Federal advisory committee is composed of 25 agencies and stakeholder groups and is chaired by the Secretary of the Interior’s designee. The AMWG makes recommendations to the Secretary of the Interior concerning operations of Glen Canyon Dam and other experimental management actions that are intended to fulfill some obligations of the Grand Canyon Protection Act of 1992. The Technical Work Group (TWG) is a subcommittee of the AMWG and provides technical advice to the AMWG. It is composed of technical and science representatives from the same agencies and stakeholder groups who serve on the AMWG. GCMRC is the primary science provider to the GCDAMP and also coordinates many aspects of the science performed by cooperators and partner agencies. The Science Advisors Program provides independent science reviews and advice at the request of the GCDAMP. The plan proposed here necessarily depends on (1) the protocol for decision-making and the requirements for scientific data reporting described in the LTEMP ROD, (2) the priorities of the GCDAMP as directed by the LTEMP ROD (see Department of the Interior, 2016b, section 6.1), (3) the priorities for monitoring and research in the conservation measures section of the Biological Opinion for the LTEMP (U.S. Department of the Interior, 2016b, LTEMP ROD attachment E), (4) the priorities for resource management and information needs established by Federal and State resource-management agencies within the GCDAMP, (5) scientific understanding about the linkage between the status of those resources and operations of Glen Canyon Dam, and (6) the need to resolve existing scientific uncertainties about the linkage between dam operations and the condition of resources. We note that resource-management prioritization is fundamentally a policy decision charged specifically to DOI for the Colorado River in Glen and Grand Canyons, as outlined most recently in the LTEMP ROD, and is not the responsibility of the GCMRC. However, it is the responsibility of the GCMRC to describe the nature of scientific understanding, the nature of scientific uncertainty, and the risk of making resourcemanagement decisions in the face of existing scientific uncertainty. The goals of science activities in the next 20 years are to inform operational decisions regarding Glen Canyon Dam operations described in the LTEMP ROD, resolve remaining scientific uncertainties, and to monitor resource trends that are affected entirely, or in part, by dam operations.

Open-File Report↗

Remotely Sensed Data Collections: Offerings from EROS

The U.S. Geological Survey (USGS) Center for Earth Resources Observation and Science (EROS) maintains a wide variety of remotely sensed data collections that contain a wealth of information about the Earth’s land surfaces. Acquired by special sensors carried aboard civilian satellites and aircraft, the images and other data in these collections provide a unique perspective of the terrestrial environment. They represent invaluable resources for scientists, resource managers, policy makers, and educators to use in studying such things as natural hazards, conservation issues, land use and economic development, and environmental change at local, regional, and global levels. Different types of sensors record different types of information, resulting in diverse data products, each with its own particular strengths. Highlighted here are eight remotely sensed data collections that are currently available from EROS.

Fact Sheet↗

Quality of surface water in the Bear River basin, Utah, Wyoming, and Idaho

The United States Geological Survey, in cooperation with the Utah Department of Natural Resources, Division of Water Rights, began a reconnaissance in 1967 to obtain essential water-quality information for the Bear River basin. The reconnaissance was directed toward defining the chemical quality of the basin’s surface waters, including suitability for specific uses, geology, and general basin hydrology. Emphasis was given to those areas where water-development projects are proposed or being considered.

Idaho, Utah, Wyoming↗

Summary report of the geology, mineral resources, engineering geology, and environmental geochemistry of the Sweetwater-Kemmerer area, Wyoming: Part B, Engineering geology

A knowledge of the engineering geologic characteristics of the Upper Cretaceous and lower Tertiary rocks is basic to assessing the effects of anticipated large-scale coal development in the Sweetwater-Kemmerer area of southwestern Wyoming. This development will include construction of railroads, highways, residences, and commercial and industrial installations, as well as surface and underground coal mines. Engineering geologic characteristics of the rocks and soils will affect all of these types of development. Engineering geologic characteristics, as used in this report, include the geotechnical properties of the various earth materials, and the behavior of these materials in natural and artificial slopes and in surface and underground coal mines. The geotechnical properties of the rocks both above and below the coal beds are important factors to consider in planning mining activities, because they control the behavior of the bedrock in response to either surface mining or underground mining. The properties of the rocks at the outcrop commonly may be so much altered from their natural state that geotechnical test results on these rocks can be false and misleading. It is commonly necessary to test drill cores in order to obtain adequate geotechnical information. The information necessary to properly evaluate the geotechnical properties of coal-bearing rocks in the Sweetwater-Kemmerer area is not currently available.

Wyoming↗

Iowa ground-water quality

The population served by ground-water supplies in Iowa (fig. L4) is estimated to be about 2,392,000, or 82 percent of the total population (U.S. Geological Survey, 1985, p. 211). The population of Iowa is distributed fairly uniformly throughout the State (fig. IB), with 59 percent residing in rural areas or towns of less than 10,000 (U.S. Bureau of the Census, 1982). Surficial aquifers, the Jordan aquifer, and aquifers that form the uppermost bedrock aquifer in a particular area are most commonly used for drinking-water supplies and usually provide ample amounts of good quality water. However, naturally occurring properties or substances such as hardness, dissolved solids, and radioactivity limit the use of water for drinking purposes in some areas of each of the five principal aquifers (fig. 2/4). Median concentrations of nitrate in all aquifers and radium-226 in all aquifers except the Jordan are within the primary drinking-water standards established by the U.S. Environmental Protection Agency (1986a). Median concentrations for dissolved solids in the surficial, Dakota, and Jordan aquifers exceed secondary drinking-water standards established by the U.S. Environmental Protection Agency (1986b). Ground water in Iowa, however, has been affected by human induced contamination. Water from some wells in surficial and the uppermost bedrock aquifers contains nitrate concentrations exceeding the primary drinking-water standard of 10 mg/L (milligrams per liter) as nitrogen. Surficial aquifers also contain detectable concentrations of pesticides and other organic substances. Standards have not been established for many of the organic substances detected, and water supplies containing these substances may continue to be used. The long-term health consequences of exposure to these substances are not known; however, the estimated number of people in Iowa exposed to pesticide contaminants is believed to exceed 750,000 or 25 percent of the population (Kelley and others, 1986.) Land-use and waste-disposal practices are believed to be responsible for most human-induced contamination in Iowa. About 33 million acres, or nearly 93 percent of the land area of Iowa, is fanned (Skow and Halley, 1986). About 56 million pounds of herbicides was used for agriculture during 1979 (Becker and Stockdale, 1980) and about 2.7 million tons of fertilizer products was used during 1985 (Skow and Halley, 1986). Additionally, 30 hazardous-waste sites are under authority of the Federal Resource Conservation and Recovery Act (RCRA) of 1976; six other sites have been listed in the National Priorities List (NPL) under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980 (U.S. Environmental Protection Agency, 1986c). As of September 1985, two Federal sites at one facility under the U.S. Department of Defense Installation Restoration Program (IRP) were designated for remedial response in accordance with CERCLA. In addition to the above sites, Iowa has 90 active municipal landfills (fig. 3C). The U.S. Geological Survey, in cooperation with the University of Iowa Hygienic Laboratory, the Iowa Department of Natural Resources, and several counties in Iowa, currently (1986) is monitoring about 1,500 public and private wells for inorganic and organic constituents. The principal objective of this program, begun in 1982, is to collect water-quality data that will describe the long-term chemical quality of the surficial and major bedrock aquifer systems in Iowa (Detroy, 1985).

Iowa↗

Statistical and descriptive summaries of water-resources data for the Cannonball River basin, North Dakota and South Dakota

Existing hydrologic data and information for the Cannonball River Basin were compiled by the U.S. Geological Survey in cooperation with the Bureau of Reclamation. This report presents a summary of surface-water quality and streamflow data, ground-water quality data, ground-water level data, water-use data, and other information compiled from the U.S. Geological Survey, Bureau of Reclamation, North Dakota Game and Fish Department, North Dakota Department of Health, North Dakota Parks and Recreation Department, North Dakota State Water Commission, and Standing Rock Sioux Tribe data bases. The data are summarized statistically or descriptively, depending on the amount or nature of the data.

Open-File Report↗

Geology and assessment of undiscovered oil and gas resources of the Eurasia Basin Province, 2008

The Eurasia Basin Petroleum Province comprises the younger, eastern half of the Arctic Ocean, including the Eurasia Basin and the outboard part of the continental margin of northern Europe in the Barents and Kara Seas. The province includes the slope and rise sedimentary prism of the Lena Delta, the north-facing outer shelf, slope, and rise of the European passive margin, and sedimentary accumulations in the deep Nansen and Amundsen Basins. The entire province lies north of the Arctic Circle beneath the polar ice cap and includes the North Pole. The province is divided into four assessment units (AUs). The Lena Prodelta AU in the eastern part of the province consists of the deep-marine part of the Lena Delta, which has been deposited across the Gakkel Ridge, an ultraslow spreading ridge. The Nansen Basin Margin AU in the southern part of the province comprises the Cenozoic passive margin sequence of the rift margin of the western (European) part of the Eurasian plate. This AU spans the continent-ocean boundary and includes prerift strata along the outer continental margin. The Nansen Basin and Amundsen Basin AUs encompass the deep abyssal plains of the Eurasia Basin. Lying south of the Gakkel Ridge spreading center, the sedimentary fill of Nansen Basin AU consists of the distal clinoform deposits shed from the western Eurasia passive margin. North of the Gakkel Ridge, Amundsen Basin AU consists of a nascent distal passive-margin sequence derived from the adjacent Lomonosov Ridge and overlying flat-lying deep marine strata shed from distant source areas in Siberia and Greenland after the Lomonosov Ridge subsided below sea level at about 50 Ma. The primary petroleum system thought to be present is sourced in ~50–44 Ma (early to middle Eocene) condensed pelagic deposits that could be widespread in the province. Mean estimates of undiscovered, technically recoverable petroleum resources include <1 billion barrels of oil (BBO) and about 1.4 trillion cubic feet (TCF) of nonassociated gas in Lena Prodelta AU, and < 0.4 BBO and 3.4 TCF nonassociated gas in the Nansen Basin Margin AU. Quantities of natural gas liquids and associated natural gas also are assessed in each of these AUs. The Nansen Basin and Amundsen Basin AUs were not quantitatively assessed because they were judged to have less than 10 percent probability of containing at least one accumulation of 50 MMBOE (million barrels of oil equivalent), the minimum probability required for evaluation in the U.S. Geological Survey Circum-Arctic Resource Appraisal.

Professional Paper↗

Linear regression model documentation for computing water-quality constituent concentrations using continuous real-time water-quality data for the Republican River, Clay Center, Kansas, July 2018 through March 2021

The Republican River is the primary inflow to Milford Lake and drains areas of Kansas, Nebraska, and Colorado. Milford Lake has been listed as impaired and designated hypereutrophic by the Kansas Department of Health and Environment because of excessive nutrient loading. Milford Lake had confirmed harmful algal blooms every summer from 2011 through 2017 and in 2020 and 2021. In the lower Republican River drainage basin, the Regional Conservation Partnership Program, administered by the Natural Resources Conservation Service, provides reimbursement to agricultural producers that implement best management practices intended to decrease sediment and nutrient runoff and loading into Milford Lake. Sediment and nutrient loads could potentially be driving factors in the development of harmful algal blooms in the reservoir. Since July 2018, the U.S. Geological Survey, in cooperation with the Kansas Water Office, has collected continuous and discrete water-quality data at the Republican River at Clay Center, Kansas, streamgage (U.S. Geological Survey station 06856600), which is about 15 river miles upstream from Milford Lake. This report documents site-specific regression models for the computation of continuous concentrations of suspended sediment, total nitrogen, total phosphorus, and total carbon developed using continuous and discrete data collected from July 24, 2018, the date of continuous water-quality monitor installation, through March 31, 2021. The objective of this study is to characterize sediment and nutrient transport in the Milford Lake drainage basin before, during, and after best management practice implementation using the models described in this report. The explanatory variable turbidity explained a high amount (72–96 percent) of the variance in suspended-sediment, total nitrogen, total phosphorus, and total carbon concentrations. Statistical plots for the four selected models showed the desired normality and homoscedasticity in residuals, and model standard error ratios indicated that recomputing each selected model after removing a randomly selected 10 percent of the data did not substantially change model coefficients.

Kansas↗

Level I water-quality inventory and monitoring, Richmond National Battlefield Park, Virginia

The U.S. Geological Survey conducted a Level I Water-Quality Inventory and Monitoring (WAQIM) data-collection effort for Richmond National Battlefield Park (Richmond NBP) from August 2001 through April 2002. The primary objective of the WAQIM program was to provide the National Park Service (NPS) and Richmond NBP with at least a nominal inventory of its natural resources and to provide those data in a data-management system consistent with park management needs. Water-quality inventory data (physical, chemical, and biological) were collected from "key" water bodies within the boundaries of Richmond NBP. The key water bodies are those waters within park boundaries that are essential to the central cultural, historical or natural resources management themes of the parks or provide habitats to threatened or endangered plants and animals. Data were collected during the fall, winter, spring, and summer over a range of hydrologic conditions. Because of the drought conditions that persisted during the study period, variations in flow between seasons were less pronounced than during normal hydrologic conditions.

Virginia↗

Development of a screening tool to examine lake and reservoir susceptibility to eutrophication in selected watersheds of the eastern and southeastern United States

This report describes a new screening tool to examine lake and reservoir susceptibility to eutrophication in selected watersheds of the eastern and southeastern United States using estimated nutrient loading and flushing rates with measures of waterbody morphometry. To that end, the report documents the compiled data and methods (R-script) used to categorize waterbodies by Carlson’s Trophic State Index. Assessments were completed for 232 lakes and reservoirs having a surface area greater than or equal to 0.1 square kilometer in watersheds that drain to the Atlantic and eastern Gulf of Mexico coasts of the United States and in watersheds within the Tennessee River Basin. Waterbodies were categorized by type—natural lakes, headwater reservoirs, and downstream reservoirs—and were assessed independently. Recursive partitioning and the model-based boosting routine were used to create four-node regression trees to group waterbodies into five endpoints from low-to-high measures of Secchi depth, and concentrations of chlorophyll a and microcystin according to shared nutrient loading, flushing rate, and morphometric characteristics. Trophic state designations were assigned based on the average value within each of the five endpoints. An application (procedure) is provided using the tool to examine the susceptibility of a given waterbody of interest to eutrophication. Results of this study can aid water-resource managers in prioritizing lake and reservoir protection and restoration efforts based on the susceptibility of these waterbodies to eutrophication relative to nutrient loading, flushing rate, and morphometric characteristics.

Scientific Investigations Report↗

Hydrogeology of the Cliff House Sandstone in the San Juan structural basin, New Mexico, Colorado, Arizona, and Utah

This report is one in a series resulting from the U.S. Geological Survey's Regional Aquifer-System Analysis (RASA) study of the San Juan structural basin that began in October 1984. Previous reports in the series describe the hydrogeology of the Dakota Sandstone (Craigg and others, 1989), Point Lookout Sandstone (Craigg and others, 1990), Morrison Formation (Dam and others, 1990), Gallup Sandstone (Kernodle and others, 1989), and Menefee Formation (Levings and others, 1990) in the San Juan structural basin. The purposes of the RASA (Welder, 1986) are to: (1) Define and evaluate the aquifer system; (2) assess the effects of past, present, and potential ground-water use on aquifers and streams; and (3) determine the availability and quality of ground water. This report summarizes information on the geology and the occurrence and quality of water in the Cliff House Sandstone, one of the primary water-bearing units in the regional aquifer system. Data used in this report were collected during the study or were derived from existing records in the U.S. Geological Survey's computerized National Water Information System (NWIS) data base, the Petroleum Information Corporation's data base, and the Dwight's ENERGYDATA Inc. BRIN data base. Although all data available for the Cliff House Sandstone were considered in formulating the discussions in the text, not all those data could be plotted on the illustrations. The San Juan structural basin is in New Mexico, Colorado, Arizona, and Utah and has an area of about 21,600 square miles (fig. 1). The structural basin is about 140 miles wide and about 200 miles long. The study area is that part of the structural basin that contains rocks of Triassic or younger age and, therefore, is less extensive than the structural basin. Triassic through Tertiary sedimentary rocks are emphasized in this study because the major aquifers in the basin are present in these rocks. The study area is about 140 miles wide (about the same as the structural basin), 180 miles long, and has an area of about 19,400 square miles. Altitudes in the study area range from about 4,500 feet in San Juan County, Utah, to about 11,000 feet in Cibola County, New Mexico. Annual precipitation in the high mountainous areas along the north and east margins of the basin is as much as 45 inches, whereas annual precipitation in the lower altitude, central basin is generally less than 8 inches. Mean annual precipitation in the study area is about 12 inches. Data obtained from documents published by the U.S. Bureau of the Census, 1980 and 1985, were used to estimate the population of the study area. The population of the study area in 1970 was estimated to be about 134,000. The population rose to about 194,000 in 1980, 212,000 in 1982, 221,000 in 1984, and then fell to about 210,000 in 1985. The economy of the basin is supported by exploration and development of petroleum, natural gas, coal, and uranium resources; urban enterprise, farming and ranching; tourism; and recreation. The rise and fall in population were related to changes in the economic strength of the mining, petroleum, and natural-gas industries, and support services. Uranium mining and milling activities grew rapidly until the late 1970's when most uranium-mining activity ended in the study area. Likewise, the oil and gas industry prospered until about 1983 and then declined rapidly, also affecting many jobs in support industries.

Arizona, Colorado, New Mexico, Utah↗

Hydrogeology of the Point Lookout Sandstone in the San Juan structural basin, New Mexico, Colorado, Arizona, and Utah

This report is one in a series resulting from the U.S. Geological Survey's Regional Aquifer-System Analysis (RASA) study of the San Juan structural basin that began in October 1984. Previous reports in the series describe the hydrogeology of the Dakota Sandstone (Craigg and others, 1989), Morrison Formation (Dam and others, 1990), Gallup Sandstone (Kernodle and others, 1989), Menefee Formation (Levings and others, 1990), and Cliff House Sandstone (Thorn and others, 1990), in the San Juan structural basin. The purposes of the RASA (Welder, 1986) are to: (1) Define and evaluate the aquifer system; (2) assess the effects of past, present, and potential ground-water use on aquifers and streams; and (3) determine the availability and quality of ground water. This report summarizes information on the geology and the occurrence and quality of water in the Point Lookout Sandstone, one of the primary water-bearing units in the regional aquifer system. Data used in this report were collected during the study or were derived from existing records in the U.S. Geological Survey's computerized National Water Information System (NWIS) data base, the Petroleum Information Corporation's database, and the Dwight's ENERGYDATA Inc. BRIN data base. Although all data available for the Point Lookout Sandstone were considered in formulating the discussions in the text, not all those data could be plotted on the illustrations. The San Juan structural basin is in New Mexico, Colorado, Arizona, and Utah and has an area of about 21,600 square miles (fig. 1). The structural basin is about 140 miles wide and about 200 miles long. The study area is that part of the structural basin that contains rocks of Triassic or younger age and, therefore, is less areally extensive than the structural basin. Triassic through Tertiary sedimentary rocks are emphasized in this study because the major aquifers in the basin are present in these rocks. The study area is about 140 miles wide (about the same as the structural basin), 180 miles long, and has an area of about 19,400 square miles. Altitudes in the study area range from about 4,500 feet in San Juan County, Utah, to about 11,000 feet in Cibola County, New Mexico. Annual precipitation in the high mountainous areas along the north and east margins of the basin is as much as 45 inches, whereas annual precipitation in the lower altitude, central basin is generally less than 8 inches. Mean annual precipitation in the study area is about 12 inches. Data obtained from documents published by the U.S. Bureau of the Census, 1980 and 1985, were used to estimate the population of the study area. The population of the study area in 1970 was estimated to be about 134,000. The population rose to about 194,000 in 1980, 212,000 in 1982, 221,000 in 1984, and then fell to about 210,000 in 1985. The economy of the basin is supported by exploration and development of petroleum, natural gas, coal, and uranium resources; urban enterprise, farming "and ranching; tourism; and recreation. The rise and fall in population were related to changes in the economic strength of the mining, petroleum, and natural-gas industries, and support services. Uranium mining and milling activities grew rapidly until the late 1970's when most uranium-mining activity ended in the study area. Likewise, the oil and gas industry prospered until about 1983 and then declined rapidly, also affecting many jobs in support industries.

Arizona, Colorado, New Mexico, Utah↗

U.S. Geological Survey Cooperative Research Units Program—A hawk’s view of 2024

Introduction The U.S. Geological Survey Cooperative Fish and Wildlife Research Units (USGS CRU) program was established in 1935 and codified by Congress in 1960 to enhance graduate education in wildlife and fisheries sciences and to facilitate research and technical assistance among natural resource agencies and universities on fisheries and wildlife management topics of mutual concern. The success of the CRU program lies in its cooperative approach. State and Federal fish and wildlife agencies determine where focused, science-based studies for wildlife and natural resource management for societal benefit are needed. The CRU scientists conduct applied research to contribute results to inform and aid partners in determining best practices for managing resources. Each Unit is a unique partnership among the U.S. Geological Survey, a host university, one or more State agencies, the Wildlife Management Institute, and the U.S. Fish and Wildlife Service.

Fact Sheet↗

Interpretation of hydrogeologic data to support groundwater management, Bazile Groundwater Management Area, northeast Nebraska, 2019—A case demonstration of the Nebraska Geocloud

Nitrate, age tracer, and continuous groundwater-level data were interpreted in conjunction with airborne electromagnetic (AEM) survey data to understand the movement of nitrate within the Bazile Groundwater Management Area (BGMA) in northeastern Nebraska. Previously published age tracer data and nitrate data indicated vertical stratification of groundwater quality. Younger groundwater sampled within shallow parts of the aquifer had higher concentrations of nitrate, with 70 percent exceeding the U.S. Environmental Protection Agency maximum contaminant level of 10 milligrams per liter. In contrast, groundwater sampled from deeper parts of the aquifer indicated that nitrate concentrations were less than 2 milligrams per liter and that groundwater likely recharged prior to widespread use of commercial fertilizer. The hydrostratigraphic interpretation of AEM profiles indicated that shallow and deep monitoring wells were often screened within the same homogenous zone of aquifer material. In contrast, test-hole logs indicated that there often are fine-grained layers within these homogenous zones that separate the shallow and deep monitoring well screens, but these fine-grained layers are not detected by the AEM technique because of decreased resolution of the AEM technique with depth. The stratification of groundwater ages and nitrate concentrations likely was caused by groundwater-flow paths of different length, location and time of recharge, and denitrification. Within paleochannels interpreted from AEM and test-hole data, pesticides detected in groundwater generally coincide with elevated nitrate concentrations. Continuous groundwater-level data from four monitoring well nests indicated that groundwater pumping can impose or increase downward hydraulic gradients and facilitate the downward movement of nitrate into deeper parts of the High Plains aquifer. Given the density of irrigation wells within the BGMA, this effect on the hydraulic gradient is likely prevalent in other areas of the BGMA. Understanding seasonal water-level changes can allow water managers to better predict and assess the hydraulic gradient and the vulnerability of groundwater in deeper parts of the High Plains aquifer. Nitrate, age tracer, and continuous groundwater-level data within the BGMA were interpreted in conjunction with AEM data as a case demonstration of the Nebraska Geocloud. The Nebraska Geocloud was initiated to protect taxpayer investments in AEM data collection and realize maximum benefit of these data by creating a publicly available, online digital database for long-term data storage. The Lower Platte North, Lower Platte South, Papio-Missouri River, Nemaha, Lower Loup, Central Platte, Upper Elkhorn, Lower Elkhorn, Lower Niobrara, and Lewis and Clark Natural Resources Districts; the University of Nebraska-Lincoln Conservation and Survey Division, Nebraska Natural Resources Commission, Nebraska Department of Natural Resources; and the U.S. Geological Survey entered a cooperative agreement to begin a program of data management and research aimed at understanding the best use of AEM for groundwater sustainability and management. Resulting case-study interpretations are provided to guide use of the Nebraska Geocloud to assess water-quality conditions and can be used by water managers and staff to address applicable water resource problems.

Nebraska↗