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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 811 records · Page 45Linked to original sources
USGS1980

Borehole geophysical measurements for hole UE25-3, Nevada Test Site, Nuclear Waste Isolation Program

Borehole geophysical measurements made in drill hole UE25a-3 with a U.S. Geological Survey research well-logging truck are presented in this paper. The purpose of these logging measurements is to provide in-situ physical properties information that is not commercially available on drill hole UE25a-3. Well logs are presented in this paper for dual-detector density, normal resistivity, gamma-ray, neutron-neutron, induced polarization, and magnetic susceptibility measurements. These data are analyzed for correlations with the core lithology. Hole-to-surface measurements made from drill hole UE25a-3 indicate the presence of two resistive bodies at depth. The deeper resistive anomaly may be related to a granitic intrusion.

Nevada↗
USGS1993

Ground-water quality at the Management Systems Evaluation Area (MSEA) near Princeton, Minnesota, 1991

The northern cornbelt sand-plains Management Systems Evaluation Area (MSEA) program is a multiagency, multistate initiative to evaluate the effects of modified and prevailing fanning systems on water quality in a sand-plain area in Minnesota and at satellite areas in North and South Dakota, and Wisconsin (Delin and others, 1992). The primary objective of the northern cornbelt sand-plains MSEA is to evaluate the effects of ridge-tillage practices in a corn and soybean farming system on ground-water quality. The Minnesota MSEA program is a cooperative study primarily between the U.S. Department of Agriculture-Agricultural Research Service, the University of Minnesota Soil Science Department, and the U.S. Geological Survey. The Minnesota Pollution Control Agency and the Department of Geology and Geophysics at the University of Minnesota are also cooperating in the evaluation of ground-water quality at the MSEA.

Minnesota↗
USGS1993

Ground-water quality at the Management Systems Evaluation Area near Princeton, Minnesota, 1991-92

The northern cornbelt sand-plains Management Systems Evaluation Area (MSEA) program is a multiagency, multistate initiative to evaluate the effects of modified and prevailing farming systems on water quality in a sand-plain area in Minnesota and at satellite areas in North and South Dakota, and Wisconsin. The primary objective of Minnesota MSEA is to evaluate the effects of ridge-tillage practices in a corn and soybean farming system on ground-water quality. The Minnesota MSEA program is a cooperative study primarily between the U.S. Department of Agriculture Agricultural Research Service, the University of Minnesota Soil Science Department, and the U.S. Geological Survey. The Minnesota Pollution Control Agency and the Department of Geology and Geophysics at the University of Minnesota are also cooperating in the evaluation of groundwater quality at the MSEA.

Minnesota↗
USGS2023

Geologic and geophysical maps of the Stockton 30’ × 60’ quadrangle, California

This pamphlet and accompanying geologic and geophysical maps are the products of cooperative efforts by the California Geological Survey (CGS) and United States Geological Survey (USGS) to compile a comprehensive, digital representation of the bedrock geology, Quaternary surficial deposits, and potential-field anomalies within the boundaries of the Stockton 30’ × 60’ quadrangle. The Stockton 30’ × 60’ quadrangle covers approximately 4,890 km 2 of Contra Costa, Alameda, San Joaquin, and Stanislaus Counties, California. From the rugged hillsides of the northern Diablo Range in the west to the San Joaquin Valley in the east, the map extends roughly 88 km across growing suburban communities of the eastern San Francisco Bay Area and Livermore Valley, grass-covered ranchlands along eastern slopes of the Diablo Range, and into the low farmlands of the San Joaquin Valley and Sacramento-San Joaquin River Delta (Figure 1). The elevation ranges from near sea level in the Delta to 1,173 meters on Mt. Diablo, the most prominent peak of the San Francisco Bay region.

California↗
USGS2023

National map of focus areas for potential critical mineral resources in the United States

Introduction The U.S. Geological Survey (USGS) launched the Earth Mapping Resources Initiative (Earth MRI) to modernize the surface and subsurface geologic mapping of the United States, with a focus on identifying areas that may have the potential to contain critical mineral resources. EarthMRI can inform strategies to ensure secure and reliable domestic critical mineral supplies for the United States as mandated by Executive Order 13817 and the Infrastructure and Jobs Act of 2021 (Public Law 117–58, 135 Stat. 529). Earth MRI is a collaborative effort between the USGS and the State geological surveys as represented by the Association of American State Geologists to identify, prioritize, and acquire new geoscience data for geographic areas, or focus areas, across the Nation that have potential to host critical mineral resources. Mapping of focus areas was based on a framework of mineral systems and their associated mineral deposit types that could possibly host critical minerals. Using readily available geologic, geophysical, geochemical, and mineral deposit data, teams of USGS scientists worked with representatives of State geological surveys in a series of workshops to outline focus areas that contain evidence of key features for one or more mineral systems. These areas can be used to guide future efforts to collect new geologic, geophysical, geochemical, and topographic data that focus on critical minerals through Earth MRI.

Fact Sheet↗
USGS2012

Geologic controls on sediment distribution and transport pathways around the Chandeleur Islands, LA., USA

Geophysical surveys around the Chandeleur Islands provide the necessary data to map the thickness and distribution of the Holocene deposit associated with this barrier island system. This system rests uncomformably on St. Bernard Delta deposits of the Mississippi Delta plain and is thinnest under the central part of the island chain and thickest at the northern and southern ends. The zone of divergence in the bidirectional littoral transport system coincides with the thin central part. An estimate of northward littoral transport rate based on lithosome age and the volume of sediment that has accumulated at the northern end of the transport cell suggests the average transport rate over the life of the system is greater than present day fair-weather estimates. This difference may be attributed to changes in transport rates through the life of the system, to changes in the rate of sea-level rise or to storms playing a more dominant role than fair-weather waves in littoral transport.

Louisiana↗
USGS2000

Bathymetric, geophysical and geologic sample data from Medicine Lake, Siskiyou County, northern California

In September, 1999, the U.S. Geological Survey acquired high-resolution bathymetry, seismic reflection profiles, and geologic sample data from Medicine Lake, a high altitude (2,036 m) lake located within the summit caldera/basin at Medicine Lake volcano (MLV), a dormant Quaternary shield volcano located in the Cascade Range, 50 km northeast of Mt. Shasta. It last erupted less than 1000 years ago.The purpose of this work was to assess whether sediments in the lake might provide a high-resolution record of the climate, volcanic and geochemical (particularly mercury) history of the region. We are still working with our data to assess whether the sediments are appropriate for further study. This report provides a summary of what we have learned to date.

California↗
USGS2018

Sediment data from vibracores collected in 2016 from Fire Island, New York

Researchers from the U.S. Geological Survey (USGS) conducted a long-term coastal morphologic-change study at Fire Island, New York, prior to and after Hurricane Sandy impacted the area in October 2012. The Fire Island Coastal Change project objectives include understanding the morphologic evolution of the barrier island system on a variety of time scales (months to centuries) and resolving storm-related effects, post-storm beach response, and recovery. In April 2016, scientists from the USGS St. Petersburg Coastal and Marine Science Center conducted sediment sampling and geophysical surveys on Fire Island to characterize and quantify spatial variability in the subaerial geology with the goal of subsequently integrating onshore geology with other surf zone and nearshore datasets. This report, along with the accompanying USGS data release , serves as an archive of sediment data from 14 vibracores collected on April 10 and 11, 2016 (USGS Field Activity Number 2016–322–FA ), along 6 transects that extend from the upper to lower subaerial shoreface at Fire Island. Sedimentologic and stratigraphic metrics (for example, sediment texture or unit thicknesses) derived from these data can be used to assess spatial and temporal trends and may aid in understanding beach evolution. Data products include sample location tables, descriptive core logs, core photographs, results of sediment grain-size analyses, and geographic information system data files with accompanying formal Federal Geographic Data Committee metadata.

New York↗
USGS2011

Geophysical bed sediment characterization of the Androscoggin River from the former Chlor-Alkali Facility Superfund Site, Berlin, New Hampshire, to the state border with Maine, August 2009

The former Chlor-Alkali Facility in Berlin, New Hampshire, was listed on the U.S. Environmental Protection Agency National Priorities List in 2005 as a Superfund site. The Chlor-Alkali Facility lies on the east bank of the Androscoggin River. Elemental mercury currently discharges from that bank into the Androscoggin River. The nature, extent, and the speciation of mercury and the production of methyl mercury contamination in the adjacent Androscoggin River is the subject of continuing investigations. The U.S. Geological Survey, in cooperation with Region I of the U.S. Environmental Protection Agency, used geophysical methods to determine the distribution, thickness, and physical properties of sediments in the Androscoggin River channel at a small area of an upstream reference reach and downstream from the site to the New Hampshire–Maine State border. Separate reaches of the Androscoggin River in the study area were surveyed with surface geophysical methods including ground-penetrating radar and step-frequency electromagnetics. Results were processed to assess sediment characteristics including grain size, electrical conductivity, and pore-water specific conductance. Specific conductance measured during surface- and pore-water sampling was used to help interpret the results of the geophysical surveys. The electrical resistivity of sediment samples was measured in the laboratory with intact pore water for comparison with survey results. In some instances, anthropogenic features and land uses, such as roads and power lines affected the detection of riverbed properties using geophysical methods; when this occurred, the data were removed. Through combining results, detailed riverbed sediment characterizations were made. Results from ground-penetrating radar surveys were used to image and measure the depth to the riverbed, depth to buried riverbeds, riverbed thickness and to interpret material-type variations in terms of relative grain size. Fifty two percent of the riverbed in the study area was covered with gravel and finer sediments. The electrically resistive river water and sediment in this study area were conducive to the penetration of the ground-penetrating radar and step-frequency electromagnetic signals and allowed for effective sediment characterization by geophysical methods. The reach between the former Chlor-Alkali Facility and the Riverside Dam, had small areas of fine sediment (estimated 11 percent of riverbed area), found on the upstream left bank and the downstream right bank, with an electromagnetic conductivity (31.4 millisiemens per meter (mS/m) maximum) that was higher than the upstream reference reach. The greatest electromagnetic conductivity (195 mS/m), pore-water specific conductance (324 mS/m) and lab measured sediment conductivity of (76.8 mS/m, measured with a direct-current resistivity test box) in the study were measured approximately 1 mile (mi) downstream of the site from a sandbar on the left bank. Reaches adjacent to and within 2 mi downstream from the site had elevated electromagnetic conductivity despite having lower estimated percentages of riverbed area covered in sediment (11, 25, and 61 percent, respectively) than the reference reach (97). Typically finer grained sediment with similar mineralogy will be more conductive. The Shelburne Reservoir is approximately 8 mi downstream from the site had the second greatest pore-water specific conductance measured, 45.8 mS/m. Many of the locations with the largest step-frequency electromagnetic values have not been sampled for pore water and sediment.

New Hampshire↗
USGS2009

Geophysical log analysis of selected test holes and wells in the High Plains Aquifer, Central Platte River Basin, Nebraska

The U.S. Geological Survey in cooperation with the Central Platte Natural Resources District is investigating the hydrostratigraphic framework of the High Plains aquifer in the Central Platte River basin. As part of this investigation, a comprehensive set of geophysical logs was collected from six test holes at three sites and analyzed to delineate the penetrated stratigraphic units and characterize their lithology and physical properties. Flow and fluid-property logs were collected from two wells at one of the sites and analyzed along with the other geophysical logs to determine the relative transmissivity of the High Plains aquifer units. The integrated log analysis indicated that the coarse-grained deposits of the alluvium and the upper part of the Ogallala Formation contributed more than 70 percent of the total transmissivity at this site. The lower part of the Ogallala with its moderately permeable sands and silts contributed some measureable transmissivity, as did the fine-grained sandstone of the underlying Arikaree Group, likely as a result of fractures and bedding-plane partings. Neither the lower nor the upper part of the siltstone- and claystone-dominated White River Group exhibited measurable transmissivity. The integrated analysis of the geophysical logs illustrated the utility of these methods in the detailed characterization of the hydrostratigraphy of the High Plains aquifer.

Nebraska↗
USGS2014

Sediment data collected in 2010 from Cat Island, Mississippi

Scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, in collaboration with the U.S. Army Corps of Engineers, conducted geophysical and sedimentological surveys in 2010 around Cat Island, Mississippi, which is the westernmost island in the Mississippi-Alabama barrier island chain. The objective of the study was to understand the geologic evolution of Cat Island relative to other barrier islands in the northern Gulf of Mexico by identifying relationships between the geologic history, present day morphology, and sediment distribution. This data series serves as an archive of terrestrial and marine sediment vibracores collected August 4-6 and October 20-22, 2010, respectively. Geographic information system data products include marine and terrestrial core locations and 2007 shoreline data. Additional files include marine and terrestrial core description logs, core photos, results of sediment grain-size analyses, optically stimulated luminescence dating and carbon-14 dating locations and results, Field Activity Collection System logs, and formal Federal Geographic Data Committee metadata.

Mississippi↗
USGS1982

3.5-kHz Data Collected in the Wilmington Canyon Area During 1980, Endeavor Cruise 80-EN-056

During 1980, geophysical data were collected seaward of New Jersey in the vicinity of Wilmington Canyon on three cruises, GYRE 80-G-7B, GYRE 80-G-BB, and ENDEAVOR 80-EN-056 (discussed here). The objectives of these surveys of the Continental Slope and upper Rise, including Wilmington Canyon and the adjacent margin, were to extend existing geophysical coverage to the south of Wilmington Canyon and to provide detailed geologic and geophysical data on the poss.ible origin and evolution of submarine canyons and on sediment transport and other processes within the canyon domain. The geology of this area near Wilmington Canyon was discussed by McGregor, Stubblefield, and others and Stubblefield and others. On ENDEAVOR Cruise 80-EN-056, during October 9-10, 1980, a series of 3.5-kHz profiles was collected. The objective of acquiring these data was to supplement data from GYRE 80-G-7B so that a bathymetric map based on 1-km-spaced grid of data could be constructed. The 3.5-k.Hz system consisted of a hull-mounted transducer and a signal correlator. Ship's speed during the survey was 10 knots (18 km/hr). Data were recorded on a strip chart at a 1-second sweep rate. Navigational control for the cruise was based on Loran C. All times given on the data and navigation plots are in Greenwich mean time (GMT or Z). The quality of the records is very good, although time marks had to be added manually. Maximum subbottom penetration was approximately 100 m. Original records may be viewed at the u.s. Geological Survey, Woods Hole, MA 02543. Microfilms of the data and 1:40,000 scale trackcharts can be purchased only from the National Geophysical and Solar-Terrestr.ial Data Center, NOAA/EDIS/NGSDC, Code D621, 325 Broadway, Boulder, Colorado, 80303 (303-497-6338).

Open-File Report↗
USGS2020

Geophysical surveys, hydrogeologic characterization, and groundwater flow model for the Truxton basin and Hualapai Plateau, northwestern Arizona

This is the third and final report in a series that describe the groundwater resources of the Hualapai Indian Reservation. These reports document the findings of a comprehensive groundwater study conducted on the reservation and adjacent areas from 2015 through 2018 by the U.S. Geological Survey in cooperation with the Bureau of Reclamation. The first report described the hydrologic framework and characterization of the Truxton aquifer on the Hualapai Indian Reservation (Bills and Macy, 2016). The second report described the hydrogeologic characterization of the Hualapai Plateau part of the reservation (Mason, Macy, and others, 2020). This report includes five chapters. Chapter A (Mason, Knight, and others, 2020) is a summary of this multichapter volume and briefly describes the study area. Chapter B (Mason, Bills, and Macy, 2020) describes the geology and hydrology of the Truxton basin and Hualapai Plateau. Chapter C (Kennedy, 2020) describes the results of a gravity geophysical survey of the Truxton basin. Chapter D (Ball, 2020) describes the findings of an airborne electromagnetic survey of the Truxton aquifer and Hualapai Plateau. Chapter E (Knight, 2020) describes the results of a transient groundwater model created for the entire Truxton aquifer both on and off the reservation. The groundwater-flow model is used to estimate projected groundwater levels based on future groundwater withdrawal scenarios.

Arizona↗
USGS2015

Lithostratigraphic, borehole-geophysical, hydrogeologic, and hydrochemical data from the East Bay Plain, Alameda County, California

The U.S. Geological Survey, in cooperation with the East Bay Municipal Utility District, carried out an investigation of aquifer-system deformation associated with groundwater-level changes at the Bayside Groundwater Project near the modern San Francisco Bay shore in San Lorenzo, California. As a part of the Bayside Groundwater Project, East Bay Municipal Utility District proposed an aquifer storage and recovery program for 1 million gallons of water per day. The potential for aquifer-system compaction and expansion, and related subsidence, uplift, or both, resulting from aquifer storage and recovery activities were investigated and monitored in the Bayside Groundwater Project. In addition, baseline analysis of groundwater and substrata properties were performed to assess the potential effect of such activities. Chemical and physical data, obtained from the subsurface at four sites on the east side of San Francisco Bay in the San Lorenzo and San Leandro areas of the East Bay Plain, Alameda County, California, were collected during the study. The results of the study were provided to the East Bay Municipal Utility District and other agencies to evaluate the chemical and mechanical responses of aquifers underlying the East Bay Plain to the future injection and recovery of imported water from the Sierra Nevada of California. Among 4 sites, 14 piezometers and 2 extensometers were installed in 6 boreholes, which ranged in depth from 460 to 1,040 feet. The lithology of drill cuttings, collected at 5- or 10-foot intervals, was described for grain size and any other noticeable features, such as wood or shell fragments. Borehole geophysical logging was performed at each site in the deepest borehole, immediately following drilling. Drill-core samples, totaling 284 feet, were collected at the Bayside site. The drill-core sediment was subsampled to determine pore-water chemistry, vertical hydraulic conductivity, and physical and mechanical properties at different depths. Depositional environment and age were determined by luminescence geochronology and fossil identification. The elemental composition of the drill-core sediments was determined by inductively coupled plasma mass spectroscopy and instrumental neutron activation by abbreviated count analysis. Mineral composition was determined by X-ray diffraction and scanning electron microscopy analysis. Groundwater samples were collected from all 14 piezometers as part of either the USGS Groundwater Ambient Monitoring and Assessment or the USGS National Water Quality Assessment program for water-quality analyses. Sample analytes included nutrients, major and minor ions, trace elements, isotopic ratios of hydrogen and oxygen in water, carbon-14, and tritium. Water-level and aquifer-system-compaction measurements, which indicated diurnal and seasonal fluctuations, were made at the Bayside Groundwater Project site. Slug tests were performed at the Bayside piezometers and nine pre-existing wells to estimate hydraulic conductivity.

California↗
USGS2018

Hydrogeophysics at societally relevant scales: Airborne electromagnetic applications and model structural uncertainty quantification

There is a critical and growing need for information about subsurface geological properties and processes over sufficiently large areas that can inform key scientific and societal studies. Airborne geophysical methods fill a unique role in Earth observation because of their ability to detect deep subsurface properties at regional scales and with high spatial resolution that cannot be achieved with groundbased measurements. Airborne electromagnetics, or AEM, is one technique that is rapidly emerging as a foundational tool for geological mapping, with widespread application to studies of water and mineral resources, geologic hazards, infrastructure, the cryosphere, and the environment. Applications of AEM are growing worldwide, with rapid developments in instrumentation and data analysis software. In this study, we summarize several recent hydrogeophysical applications of AEM, including examples drawn from a recent survey in the Mississippi Alluvial Plain (MAP). In addition, we discuss developments in computational methods for geophysical and geological model structural uncertainty quantification using AEM data, and how these results are used in a sequential hydrogeophysical approach to characterize hydrologic parameters and prediction uncertainty.

Conference Paper↗
USGS1974

Geologic map of the Monrovia Quadrangle, Liberia

As part of a program undertaken cooperatively by the Liberian Geological Survey and the U. S. Geological Survey, under the sponsorship of the Government of Liberia and the Agency for International Development, U. S. Department of State, Liberia was mapped by geologic and geophysical methods during the period 1965 to 1972.- The resulting geologic and geophysical maps are published in ten folios, each covering one quadrangle (see index map). The Monrovia quadrangle was systematically mapped by the author from June 1971 to July 1972. Field data provided by private companies and other members of the LGS-USGS project were used in map compilation, and are hereby acknowledged. Interpretation of gravity data (Behrendt and Wotorson, 1974, c), and total-intensity aeromagnetic and total count gamma radiation surveys (Behrendt and Wotorson, 1974, a, and b) were also used in the compilation, as were other unpublished geophysical data furnished by Behrendt and Wotorson (near-surface, regional magnetic component, and geologic correlations based on aeromagnetic and radiometric characteristics).

Monrovia Quadrangle↗
USGS2011

Digitized data from ground geophysical surveys in Afghanistan: A website for distribution of data

This document describes the process of digitization of a 1974 report on geophysical work undertaken by Soviet geophysicists in southern and eastern Afghanistan. These data, uncovered in Afghanistan, represent magnetic and electrical ground surveys for which locations are not well defined. Due to lack of location information, these surveys were georeferenced using the cities, rivers, and surrounding geology found on the maps used to plot survey locations. A geologic map found in the Soviet report contains profile lines that correspond to the geophysical maps, allowing these data to be georeferenced. The profiles correspond to sets of resistivity, chargeabiliy, and magnetic data. Some datasets were presented as graphs and needed to be gridded into a useable image. Only the vertical component of the magnetic field was collected, so conversion to total field anomaly was necessary. The magnetic data were collected in either gammas or milliorstead, both of which required conversion to standard SI units. To be useful to modern studies, the datasets and images contained in this report have been digitized, georeferenced, and in some cases converted into computer-ready formats.

Open-File Report↗
USGS2020

Passive seismic survey of sediment thickness, Dasht-e-Nawar basin, eastern Afghanistan

Exploration of water resources is needed for public supply, extraction of mineral resources, and economic development in Afghanistan. Remotely-sensed data are useful for identifying the general nature of surface sediments, however, “boots on the ground” geophysical surveys or drilling programs are needed to quantify the thickness of sediments or aquifers. The nature of such investigations presents a risk to field crews that may prohibit exploration of potentially valuable aquifers or mineral resources. The Dasht-e-Nawar basin, in east-central Afghanistan, contains a 400 km2 playa that includes evaporative mineral deposits, particularly lithium, which has been of interest since the 1970s. However, exploration of the basin, as with many areas of Afghanistan, has been hampered by decades of conflict. In 2014, an investigation of the basin was conducted by the U.S. Department of Defense Task Force for Business and Stability Operations (TFBSO), and their contractor, in cooperation with the U.S. Geological Survey (USGS). For this investigation the USGS compared the results of a rapid passive seismic survey of basin sediment thickness to the results of an independently conducted gravity survey of the same area. Each point measurement for the passive seismic method requires less than 30 minutes in the field by one person. The technique utilizes ambient seismic noise without an external sound source such as required by traditional seismic surveys. Additionally, the technique does not require external sensor arrays, which can be kilometers long for some geophysical techniques. The passive seismic equipment used in this study weighs approximately 1 kilogram and is about 10 cm3 in size. Although relatively new for assessment of sediment thickness, several investigations have found this method to be capable of estimating sediment thicknesses, in the 10’s to 1000 meter range, in settings with unconsolidated sediment over bedrock and a contrast in acoustic impedance. In this investigation, the gravity survey was conducted during a period of 3 weeks by an experienced field crew; required a detailed, centimeter-scale land elevation survey; and required laboratory analyses of sediment and rock densities to interpret the gravity data. In contrast, the passive seismic survey was collected by two inexperienced operators over a period of 8 days and required no additional data to interpret. Due to security restrictions, USGS personnel could not visit the site and the seismic operator was trained immediately prior to the field work. Although the quality of the seismic survey was affected by strong afternoon winds, and by the inexperience of the field operator, the results were fairly comparable to the gravity survey. Similar basin sediment thicknesses and patterns in sediment thickness were identified by both surveys in the basin with an estimated maximum thickness of approximately 170 m. The passive seismic technique required substantially less field resources and time than would be required by other geophysical surveys. Although this method will not be effective in all geologic settings, it may be a valuable assessment tool for use before conducting other, more intensive, geophysical efforts or drilling programs, especially in regions with elevated security risks such as Afghanistan.

Dasht-e-Nawar basin↗