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

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At least 91 records · Page 5Linked to original sources
USGS2014

Geologic framework for the national assessment of carbon dioxide storage resources: U.S. Gulf Coast

This report presents 27 storage assessment units (SAUs) within the United States (U.S.) Gulf Coast. The U.S. Gulf Coast contains a regionally extensive, thick succession of clastics, carbonates, salts, and other evaporites that were deposited in a highly cyclic depositional environment that was subjected to a fluctuating siliciclastic sediment supply and transgressive and regressive sea levels. At least nine major depositional packages contain porous strata that are potentially suitable for geologic carbon dioxide (CO 2 ) sequestration within the region. For each SAU identified within these packages, the areal distribution of porous rock that is suitable for geologic CO 2 sequestration is discussed, along with a description of the geologic characteristics that influence the potential CO 2 storage volume and reservoir performance. These characteristics include reservoir depth, gross thickness, net-porous thickness, porosity, permeability, and groundwater salinity. Additionally, a characterization of the overlying regional seal for each SAU is presented. On a case-by-case basis, strategies for estimating the pore volume existing within structurally and (or) stratigraphically closed traps are also presented. Geologic information presented in this report has been employed to calculate potential storage capacities for CO 2 sequestration in the SAUs that are assessed herein, although complete assessment results are not contained in this report.

Alabama, Arkansas, Florida, Georgia, Kentucky, Lou↗
USGS2004

Water Quality in the Nation's Streams and Aquifers Overview of Selected Findings, 1991-2001

This report accompanies the publication of the last 15 of 51 river basin and aquifer assessments by the USGS National Water-Quality Assessment (NAWQA) Program during 1991?2001. It highlights selected water-quality findings of regional and national interest through examples from river basins and aquifer systems across the Nation. Forthcoming reports in the USGS series ?The Quality of Our Nation?s Waters? will present comprehensive national syntheses of information collected in the 51 study units on pesticides in water, sediment, and fish; volatile organic compounds in major aquifers used for domestic and public supply; nutrients and trace elements in streams and ground water; and aquatic ecology. This report, summaries of the 51 water-quality assessments, and a 1999 national synthesis of information on nutrients and pesticides, are available free of charge as USGS Circulars and on the World Wide Web at http://water.usgs.gov/nawqa/nawqa_sumr.html.

Circular↗
USGS2003

Results of elemental and stable isotopic measurements, and dietary composition of Arctic grayling (Thymallus arcticus) collected in 2000 and 2001 from the Fortymile River Watershed, Alaska

We report the results of the elemental and stable isotopic analyses, as well as the composition of stomach contents, of Arctic grayling (Thymallus arcticus), an ecologically important resident freshwater sport and subsistence fish in the Fortymile River Mining District of the Interior Highlands Ecoregion in eastern Alaska. These data are presented here as a data compilation with minimal interpretation or discussion. Further analyses of the data will be presented elsewhere. The study area has been mined for placer gold for over a century and is currently experiencing renewed mineral exploration activity. The results for the analysis of 40 inorganic elements are reported for grayling muscle (fillet) tissue, liver tissue, and stomach contents from 34 individuals caught at 11 sites within the watershed. The 11 sites were classified as occurring within the following lithologies: metavolcanic (7 sites), metasedimentary (3 sites), and granitic intrusion (1 site). This information (along with fish tissue stable isotope data) is critical in the assessment of the influence of regional lithology on the fish chemical composition, especially the trace metal content. We report the nitrogen, carbon, and sulfur stable isotope composition of muscle samples. Nitrogen isotopes appear homogeneous (d15N = 7.6 to 9.7 permil) whereas carbon and sulfur isotope compositions of the same samples span a range from d 13C = ?33.1 to ?25.8 permil, and d 34S = ?8.4 to 8.2 permil. Stomach content material was examined for the occurrence and frequency of macroinvertebrate composition and diversity in three individual fish. Results showed a high degree of diversity with 9 to 15 invertebrate taxa; both aquatic and terrestrial forms were represented.

Open-File Report↗
USGS2017

Status of natural and human environment

This report present the results of the 2017 AMAP Assessment of Adaptation Actions for a changing Arctic (AACA): Perspectives form the Bering-Chukchi-Beaufort Region. This is one of three pilot study regions included in the AACA project. AACA is the first AMAP assessment dealing with adaptation actions and how to meet possible Arctic futures in these times of rapid chance. Information contained in this report is fully referenced and based first and foremost on peer-reviewed and published results of research and monitoring undertaken within the past decade. Care has been taken to ensure that no critical probability statements are based on non-peer-reviewed materials Access to reliable and up-to-date information is essential for the development of science-based decision-making regarding ongoing changes in the Arctic and their global implications.

Bering-Chukchi-Beaufort region↗
USGS1996

Summary of hydrogeologic controls on ground-water flow at the Nevada Test Site, Nye County, Nevada

The underground testing of nuclear devices has generated substantial volumes of radioactive and other chemical contaminants below ground at the Nevada Test Site (NTS). Many of the more radioactive contaminants are highly toxic and are known to persist in the environment for thousands of years. In response to concerns about potential health hazards, the U.S. Department of Energy, under its Environmental Restoration Program, has made NTS the subject of a long-term investigation. Efforts supported through the U.S. Department of Energy program will assess whether byproducts of underground testing pose a potential hazard to the health and safety of the public and, if necessary, will evaluate and implement steps to remediate any of the identified dangers. Test-generated contaminants have been introduced over large areas and at variable depths above and below the water table throughout NTS. Evaluating the risks associated with these byproducts of underground testing presupposes a knowledge of the source, transport, and potential receptors of these contaminants. Ground-water flow is the primary mechanism by which contaminants can be transported significant distances away from the initial point of injection. Flow paths between contaminant sources and potential receptors are separated by remote areas that span tens of miles. The diversity and structural complexity of the rocks along these flow paths complicates the hydrology of the region. Although the hydrology has been studied in some detail, much still remains uncertain about flow rates and directions through the fractured-rock aquifers that transmit water great distances across this arid region. Unique to the hydrology of NTS are the effects of underground testing, which severely alter local rock characteristics and affect hydrologic conditions throughout the region. Any assessment of the risk must rely in part on the current understanding of ground-water flow, and the assessment will be only as good as the understanding itself. This report summarizes what is known and inferred about ground-water flow throughout the NTS region. The report identifies and updates what is known about some of the major controls on ground-water flow, highlights some of the uncertainties in the current understanding, and prioritizes some of the technical needs as related to the Environmental Restoration Program. An apparent deficiency in the current understanding is a lack of knowledge about flow directions and rates away from major areas of testing. Efforts are necessary to delineate areas of downgradient flow and to identify factors that constrain and control flow within these areas. These efforts also should identify the areas most critical to gaining detailed understanding and to establishing long-term monitoring sites necessary for effective remediation.

Nevada↗
USGS2026

Spectral characteristics and mapping of lithium-rich playas in the Basin and Range Province, western United States

This report presents a comprehensive set of prospectivity maps for lithium in brines located within the playas of the Basin and Range Province of western United States. The prospectivity assessment is based on criteria established in the descriptive deposit model outlined in a previous U.S. Geological Survey report, with a focus on regional remote sensing methodologies. The playas within the study area have been systematically ranked according to several key factors, including size, the presence and abundance of source rocks, vegetation as an indicator of water availability, documented prospects, and data products derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor. Notably, the deposits in the playa of Clayton Valley make it stand out as the sole lithium brine-producing playa in the United States. The ASTER sensor provides optimal regional coverage, characterized by a 60-kilometer swath width and unique multispectral capabilities that are not available with other remote sensing instruments. This report and the accompanying maps are intended to serve as resources for further multidisciplinary assessments of lithium or other elements or commodities where prospectivity can be inferred from the presence of proxies such as alteration minerals.

Arizona, Baja California, California, Chihuahua, I↗
USGS2010

Connecticut Highlands technical report— Documentation of the regional rainfall-runoff model

This report provides the supporting data and describes the data sources, methodologies, and assumptions used in the assessment of existing and potential water resources of the Highlands of Connecticut and Pennsylvania (referred to herein as the “Highlands”). Included in this report are Highlands groundwater and surface-water use data and the methods of data compilation. Annual mean streamflow and annual mean base-flow estimates from selected U.S. Geological Survey (USGS) gaging stations were computed using data for the period of record through water year 2005. The methods of watershed modeling are discussed and regional and sub-regional water budgets are provided. Information on Highlands surface-water-quality trends is presented. USGS web sites are provided as sources for additional information on groundwater levels, streamflow records, and ground- and surface-water-quality data. Interpretation of these data and the findings are summarized in the Highlands study report.

Connecticut↗
USGS2012

Scenarios of land use and land cover change in the conterminous United States: Utilizing the special report on emission scenarios at ecoregional scales

Global environmental change scenarios have typically provided projections of land use and land cover for a relatively small number of regions or using a relatively coarse resolution spatial grid, and for only a few major sectors. The coarseness of global projections, in both spatial and thematic dimensions, often limits their direct utility at scales useful for environmental management. This paper describes methods to downscale projections of land-use and land-cover change from the Intergovernmental Panel on Climate Change's Special Report on Emission Scenarios to ecological regions of the conterminous United States, using an integrated assessment model, land-use histories, and expert knowledge. Downscaled projections span a wide range of future potential conditions across sixteen land use/land cover sectors and 84 ecological regions, and are logically consistent with both historical measurements and SRES characteristics. Results appear to provide a credible solution for connecting regionalized projections of land use and land cover with existing downscaled climate scenarios, under a common set of scenario-based socioeconomic assumptions.

Global Environmental Change↗
USGS2019

Drinking water quality in the glacial aquifer system, northern USA

Groundwater supplies 50% of drinking water worldwide, but compromised water quality from anthropogenic and geogenic contaminants can limit usage of groundwater as a drinking water source. Groundwater quality in the glacial aquifer system, USA (GLAC), is presented in the context of a hydrogeologic framework that divides the study area into 17 hydrogeologic terranes. Results are reported at aquifer-system scale and regional (terrane) scale. This paper presents a quantitative assessment of groundwater quality in the GLAC using data from numerous sources for samples collected 2005–2013, compared to health-based and aesthetic (non-health) benchmarks, and evaluated with areal and population metrics. Concentrations above a benchmark are considered high. Trace elements are widespread across the study area, with an estimated 5.7 million people relying on groundwater with high concentrations of one or more trace elements; manganese and arsenic are most often at high concentration. Nitrate is found at high concentration in 4.0% of the study area, serving about 740 thousand people. Organic compounds including pesticides and volatile organic compounds are high in 2.0% of the assessed study area, with about 870 thousand people relying on groundwater with high concentrations of an organic compound. High arsenic and manganese concentrations occur primarily in the terranes with thick, stratigraphically complex, fine-grained glacial sediment, coincident with groundwater under reducing conditions (indicated by iron concentrations >100 μg/L); high nitrate is uncommon in those same terranes. When nitrate is high in thick, fine-grained, complex terranes, though, it is much more commonly associated with groundwater under more oxidizing conditions. Common geogenic trace elements occur at high concentration due to characteristic geologic and geochemical conditions. Conversely, anthropogenic nitrate and organic compounds are introduced at or near the land surface. High concentrations of nitrate or organic compounds are generally limited to areas in proximity where people live and use the chemicals.

Science of Total Environment↗
USGS2006

Coastal monitoring of the May 2005 dredge disposal offshore of Ocean Beach, San Francisco, Calif.

Ocean Beach, California, contains an erosion hot spot in the shadow of the San Francisco ebb tidal delta south of Sloat Boulevard that threatens valuable public infrastructure as well as the safe recreational use of the beach. In an effort to reduce the erosion at this location and avoid hazardous navigation conditions at the current disposal site (SF-8), a new plan for the management of sediment dredged annually from the main shipping channel at the mouth of Francisco Bay was implemented in May 2005 by the United States Army Corps of Engineers, San Francisco District (COE). The objective for COE was to perform a test dredge disposal of ~230,000 m 3 (300,000 yd 3 ) of sand just offshore of the erosion hot spot, in depths between approximately 9 and 14 m. This disposal site was chosen because it is in a location where the strong tidal currents associated with the mouth of San Francisco Bay and waves can potentially feed sediment toward the littoral zone in the reach of the beach that is experiencing critical erosion. The onshore migration of sediment from the target disposal location might feed the primary longshore bar or the nearshore zone, and provide a buffer to erosion that peaks during winter months when large waves impact the region. The U.S. Geological Survey (USGS), in collaboration with the Sea Floor Mapping Lab (SFML) of California State University, Monterey Bay, monitored the initial bathymetric evolution of the test dredge disposal site and the adjacent coastal region from May 2005 to November 2005. This paper reports on this monitoring effort and assesses the short-term coastal response.

California↗
USGS2002

Assessment of undiscovered deposits of gold, silver, copper, lead, and zinc in the United States: A Portable Document (PDF) recompilation of USGS Open-File Report 96-96 and Circular 1178

This publication contains the results of a national mineral resource assessment study. The study (1) identifies regional tracts of ground believed to contain most of the nation's undiscovered resources of gold, silver, copper, lead, and zinc in conventional types of deposits; and (2) includes probabilistic estimates of the amounts of these undiscovered resources in most of the tracts. It also contains a table of the significant known deposits in the tracts, and includes descriptions of the mineral deposit models used for the assessment. The assessment was previously released in two major publications. The conterminous United States assessment was published in 1996 as USGS Open-File Report 96-96. Subsequently, the Alaska assessment was combined with the conterminous assessment in 1998 and released as USGS Circular 1178. This new recompilation was undertaken for several reasons. First, the graphical browser software used in Circular 1178 was ONLY compatible with the Microsoft Windows operating system. It was incompatible with the Macintosh operating system, Linux, and other types of Unix computers. Second, the browser on Circular 1178 is much less intuitive to operate, requiring most users to follow a tutorial to understand how to navigate the information on the CD. Third, this release corrects several errors and numbering inconsistencies in Circular 1178.

Open-File Report↗
USGS2015

Estimated annual agricultural pesticide use for counties of the conterminous United States, 2008-12

Annual county-level pesticide use was estimated for 423 herbicides, insecticides, and fungicides applied to agricultural crops grown in the conterminous United States during 2008–12. For all States except California, pesticide-use data were compiled from proprietary surveys of farm operations located within U.S. Department of Agriculture Crop Reporting Districts (CRDs). Surveyed pesticide-use data were used in conjunction with county annual harvested-crop acres reported by the U.S. Department of Agriculture 2007 and 2012 Censuses of Agriculture and the 2008–11 County Agricultural Production Survey to calculate use rates per harvested-crop acre, or an “estimated pesticide use” (EPest) rate, for each crop by year. County-use estimates were then calculated by multiplying EPest rates by harvested-crop acres for each pesticide crop combination. Use estimates for California were obtained from annual Department of Pesticide Regulation-Pesticide Use Reports. Proprietary surveyed pesticide-use data were not available for all CRDs and years. When pesticide-survey data were unavailable for a CRD in a particular year, EPest extrapolated rates were calculated from adjoining or nearby CRDs to ensure that pesticide use was estimated for all counties where harvested-crop acres were reported. Two estimation methods were used—EPest-low and EPest high—and differed in how they treated situations when a CRD was surveyed and pesticide use was not reported for a particular pesticide-by-crop combination. California pesticide-use estimates were not extrapolated; therefore, EPest-low and EPest-high are the same for counties in California. This data series is a continuation of the 1992–2009 pesticide-use estimates reported by Stone (2013). It is an update of estimates for 2008–9 (Stone, 2013), as well as an update of the 2010–11 preliminary estimates reported by Baker and Stone (2013). EPest values from these compilations (1992–2012) are suitable for making national, regional, and watershed assessments of annual pesticide use. County-level estimates are provided to make it easier to compile watershed assessments; however, users should be aware there is a greater degree of uncertainty in individual county-level estimates when compared to CRD or State-level estimates. This report provides EPest-low and EPest-high annual agricultural pesticide use for counties of the conterminous United States for 423 compounds during 2008–12 in tab-delimited files organized by compound, year, State Federal Information Processing Standard (FIPS) code, county FIPS code, and amount in kilograms (kg). EPest-high county pesticide-use estimates were divided into tables 1 through 7 by pesticide name: Table 1: 2, 4-D through Chlorantraniliprole Table 2: Chlorethoxyfos through Diflufenzopyr Table 3: Dimethenamid through Gibberellic acid Table 4: Glufosinate through Metiram Table 5: Metolachlor through Propazine Table 6: Propiconazole through Triasulfuron Table 7: Tribenuron methyl through Zoxamide EPest-low county pesticide-use estimates were divided into tables 8 through 14 by pesticide name: Table 8: 2, 4-D through Chlorantraniliprole Table 9: Chlorethoxyfos through Diflufenzopyr Table 10: Dimethenamid through Gibberellic acid Table 11: Glufosinate through Metiram Table 12: Metolachlor through Propazine Table 13: Propiconazole through Triasulfuron Table 14: Tribenuron methyl through Zoxamide

Data Series↗
USGS1993

Petroleum exploration plays and resource estimates, 1989, onshore United States; Region 1, Alaska; Region 2, Pacific Coast

This study provides brief discussions of the petroleum geology, play descriptions, and resource estimates of 220 individually assessed exploration plays in all 80 onshore geologic provinces within nine assessment regions of the continental United States in 1989; these 80 onshore provinces were assessed in connection with the determination of the Nation's estimated undiscovered resources of oil and gas. The present report covers the 25 provinces that make up Region 1, Alaska, and Region 2, Pacific Coast. It is our intention to issue Region 3, Colorado Plateau and Basin and Range, and Region 4, Rocky Mountains and Northern Great Plains, in book form as well. Regions 5 through 9 (West Texas and Eastern New Mexico, Gulf Coast, Midcontinent, Eastern Interior and Atlantic Coast) will be released individually, as Open-File Reports.

Bulletin↗
USGS1986

Methods for hydrologic monitoring of surface mining in the central-western United States

The regulations promulgated pursuant to the Surface Mining Control and Reclamation Act require the monitoring of potentially impacted hydrologic systems before, during, and after mining operations. This report details characteristics and processes that commonly determine the most acceptable approaches to hydrologic monitoring in the arid and semiarid central-western United States. No single approach is best for all hydrologic systems; consideration of basin characteristics, regulatory requirements, and regional patterns in hydrologic systems is necessary in any well-designed monitoring program for hydrologic-impact assessment. This report describes processes and characteristics that control the surface and subsurface hydraulics, as well as the water quality, of typical hydrological systems being mined in the central-western United States. After a discussion of these processes and characteristics, three examples are presented that describe acceptable, but nonexclusive, approaches to hydrologic monitoring network design. (USGS)

Open-File Report↗
USGS2013

Multi-regional synthesis of temporal trends in biotic assemblages in streams and rivers of the continental United States

Biotic assemblages in aquatic ecosystems are excellent integrators and indicators of changing environmental conditions within a watershed. Therefore, temporal changes in abiotic environmental variables often can be inferred from temporal changes in biotic assemblages. Algae, macroinvertebrate, and fish assemblage data were collected from 91 sampling sites in 4 geographic regions (northeastern/north-central, southeastern, south-central, and western), collectively encompassing the continental United States, from 1993 to 2009 as part of the U.S. Geological Survey National Water-Quality Assessment Program. This report uses a multivariate approach to synthesize temporal trends in biotic assemblages and correlations with relevant abiotic parameters as a function of biotic assemblage, geographic region, and land use. Of the three groups of biota, algal assemblages had temporal trends at the greatest percentage of sites. Of the regions, a greater percentage of sites in the northeastern/north-central and western regions had temporal trends in biotic assemblages. In terms of land use, a greater percentage of watersheds draining agricultural, urban, and undeveloped areas had significant temporal changes in biota, as compared to watersheds with mixed use. Correlations between biotic assemblages and abiotic variables indicate that, in general, macroinvertebrate assemblages correlated with water quality and fish assemblages correlated with physical habitat. Taken together, results indicate that there are regional differences in how individual biotic assemblages (algae, macroinvertebrates, and fish) respond to different abiotic drivers of change.

Continental United States↗
USGS2000

Maps showing geology, oil and gas fields, and geologic provinces of Iran

This digitally compiled map includes geology, oil and gas field centerpoints, geologic provinces, and major faults of Iran with some of these components extended into geographically adjacent areas. This digital compilation is an interim product of the U.S. Geological Survey's World Energy Project (WEP) and part of a series on CD-ROM. The goal of the WEP is to assess the undiscovered, technically recoverable oil and gas resources of the world and report the result of this assessment in the year 2000. For data management purposes, the world was divided into eight energy regions corresponding approximately to the economic regions of the world as defined by the U.S. Department of State.

Open-File Report↗