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Filters: Tags: gravitational field (earth) (X) > partyWithName: Geology, Geophysics, and Geochemistry Science Center (X)

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Gravity data were collected from 2006 through 2015 to assist in mapping subsurface geology in the southern San Luis Basin, northern New Mexico. This data release provides principal facts for 566 new gravity stations that were acquired to fill in gaps in the existing public gravity data coverage.
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Physical properties of geologic units are important for geophysical interpretation because they provide the tie between lithology and geophysical fields. For gravity data, the applicable physical property is bulk density, which is the overall mass per unit volume of rocks, sediments, and their pore spaces. Bulk dry density is the mass per unit volume measured when the sample is dry. Saturated density is the mass per unit volume measured when the sample is saturated with fresh water, which has a density of 1,000 kg/m^3. The two values are commonly compared in order to determine the porosity of a sample, that is, the percentage of the volume that is composed of open space. Density is commonly reported in kilograms...
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Gravity data were collected from 2016 through 2018 to assist in mapping subsurface geology in northeastern Iowa. This data release provides principal facts for 1080 new gravity stations that were acquired to supplement existing public gravity data coverage. References cited: Blakely, R.J., 1995, Potential Theory in Gravity and Magnetic Applications, Cambridge University Press, 441 p. International Association of Geodesy, 1971, Geodetic reference system 1967: International Association of Geodesy Special Publication No. 3, 116 p. Morelli, C., ed., 1974, the International gravity standardization net 1971: International Association of Geodesy Special Publication no.4, 194 p. Plouff, Donald, 1977, Preliminary documentation...
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Gravity data were collected during three separate campaigns during July of 2013, August and September of 2014, and September and October of 2020 at 168 sites on and around the Stillwater layered mafic complex in southern Montana. Measurements were taken with Lacoste & Romberg G-64, G-550, and G-161 gravimeters and reduced to obtain the complete Bouguer anomaly, with reference ties to absolute base stations at U.S. Post Offices in Spokane, Washington (2014), Billings (2013-2014) and Livingston (2020), Montana. This data release includes principal facts for 168 new gravity stations and shapefiles with field locations.
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Surface electrical resistivity tomography, magnetic, and gravity surveys were conducted in July 2017 in the greater East River Watershed near Crested Butte Colorado with a focused effort in Redwell Basin as part of a broader study of the role of bedrock groundwater in the hydrogeology of mineralized mountain watersheds. Approximately ten kilometers of total field magnetics data were acquired on July 29, 2017 with a Geometrics G-858 cesium vapor magnetometer that detects changes in deep (tens of meters to kilometers) geologic structure based on variations in the magnetic properties of different formations. This data release includes the raw and processed magnetics data. They are provided as digital data, and data...
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Note: this data release is currently being revised and is temporarily unavailable. This data release is a compilation of the locations of airborne geophysical surveys in the United States. The inventory documents public airborne geophysical surveys primarily flown by or contracted by the USGS from 1943 to present. In addition, surveys from the State of Alaska, Department of Natural Resources, Division of Geological and Geophysical Surveys (DGGS): Airborne GeophysWeb, the Bureau of Land Management, the Department of Energy and other state agencies have also been included. The surveys have contributed to studies under USGS programs including Water, Geologic Mapping, Minerals, Energy, Environmental Health, Ecosystems,...
Categories: Data, Data Release - Under Revision; Types: ArcGIS REST Map Service, ArcGIS Service Definition, Downloadable, Map Service; Tags: Alabama, Alaska, Arizona, Arkansas, California, All tags...
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Regional surface elevation grid files (provided in Grid eXchange File format) were used to study crustal architecture beneath the Southern Midcontinent (USA) by McCafferty and others (2019). The study covered a rectangular, multi-state area of 924 by 924 kilometers centered on Missouri, and a corresponding volume extending from the topographic surface to a depth of 50 kilometers below sea level. The grid files (magnetic field observation surface, topographic surface, Precambrian basement surface, and Moho interface) were used to construct templates and initial physical property models for 3D inversions. A masked version of the Precambrian basement surface grid was used to remove inverted densities and magnetic susceptibilities...
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The U.S. Geological Survey (USGS) collected rock physical property measurements to help understand causative sources of gravity and magnetic survey anomalies in the Iron Mountain-Menominee region, Michigan-Wisconsin. A total of 2,356 measurements of magnetic susceptibility and density from 152 locations have been conducted on Precambrian rocks. The measurements aid in interpretation of newly acquired ground-based gravity and airborne magnetic data that are helping to understand concealed Precambrian geology and potential mineral resources. Multiple measurements were made at each location and sample lithology units were derived from existing USGS geologic maps noted in the supplemental information section of the...
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Surface electrical resistivity tomography (ERT), time-domain electromagnetics (TEM), nuclear magnetic resonance (NMR), magnetics, and gravity data were acquired in 2016, 2017 and 2018 in the greater East River Watershed near Crested Butte Colorado with a focused effort in Redwell Basin. Five ERT profiles were acquired within Redwell Basin and Brush Creek to map geologic structure at depths up to 40 meters, depending on the subsurface resistivity, using the Advanced Geosciences, Inc. SuperSting R8 resistivity meter. Approximately ten kilometers of total field magnetics data were acquired with a Geometrics G-858 cesium vapor magnetometer that detects changes in deep (tens of meters to kilometers) geologic structure...
Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Brush Creek, Colorado, Crested Butte, East River, Environmental Health, All tags...
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Surface electrical resistivity tomography, magnetic, and gravity surveys were conducted in July 2017 in the greater East River Watershed near Crested Butte Colorado with a focused effort in Redwell Basin as part of a broader study of the role of bedrock groundwater in the hydrogeology of mineralized mountain watersheds. Ten gravity stations were acquired with a LaCoste and Romberg G-model relative gravimeter to map density variations. This data release includes principal facts for the gravity stations provided as digital data. Data fields are defined in the data dictionary.
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The U.S. Geological Survey collected ground gravity data as part of a helicopter reconnaissance campaign of the Democrat Creek alkaline complex and Deer Peak quadrangle in the Wet Mountains, Colorado. A total of 60 measurements were collected using a LaCoste and Romberg gravity meter. High accuracy geographic coordinates and elevations were collected using a survey grade Leica GS16 differential GPS system. These data supplement existing public gravity data to aid in the interpretation of a newly collected, high-resolution airborne magnetic survey (Grauch et al., 2023). Grauch, V.J.S., Anderson, E.D., Brown, P.J., and Allen Langhans, A.D., 2023, Airborne magnetic and radiometric survey of the Wet Mountains and surrounding...
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Regional grid files and 3D voxel models were used to study crustal architecture beneath the Southern Midcontinent (USA) by McCafferty and others (2019). The study covered a rectangular, multi-state area of 924 by 924 kilometers centered on Missouri, and a corresponding volume extending from the topographic surface to a depth of 50 kilometers below sea level. The grid files consist of surface grids (magnetic field observation surface, topographic surface, Precambrian basement surface, and Moho interface) used to construct templates and initial physical property models for 3D inversions, observed geophysical data grids (Bouguer gravity anomaly and reduced-to-pole (RTP) aeromagnetic anomaly) used in the inversions,...
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This 3D voxel model of density in GOCAD format was used to study crustal architecture beneath the Southern Midcontinent (USA) by McCafferty and others (2019). The study covered a rectangular, multi-state area of 924 by 924 kilometers centered on Missouri, and a corresponding volume extending from the topographic surface to a depth of 50 kilometers below sea level. The 3D voxel model describes the density of the crust and upper mantle as interpreted using 3D inversion. The masked version excludes densities in areas where the Precambrian basement surface elevations are unknown. The individual voxel elements are 2,000 by 2,000 meters by 500 meters thick. The GOCAD voxel (GRID3D or Voxet) file format is documented...
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High resolution magnetic and gravity gradient data were collected using the HeliFalcon airborne gravity gradiometry system together with a stinger-mounted magnetometer. The survey took place out of the Sullivan, Missouri airport during March of 2014. The survey covers a 35 x 37 square-kilometer area centered on the Pea Ridge iron oxide-apatite rare-earth element deposit, which is located about halfway between the towns of Sullivan and Potosi, Missouri. Data were collected along north-south flight lines spaced 400 m apart with east-west tie lines flown every 4000 m. A nominal flight height above terrain of 80 m was maintained except where safety dictated a higher elevation. A total of 3538 line km of data were collected....
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Gravity data were collected from 2016 through 2019 to assist in mapping surface and subsurface geology in the central Upper Peninsula of Michigan and in neighboring northeastern Wisconsin. This data release provides principal facts for 1536 new gravity stations that were acquired to supplement existing public gravity data coverage.
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Gravity data were collected in August of 2019 at 21 sites on and around Iliamna Volcano and Anchorage, Alaska. Measurements were taken with a Lacoste & Romberg G-161 meter and reduced to obtain the complete Bouguer anomaly. A total of 39 magnetic susceptibility measurements were taken at 13 locations using a ZH Instruments SM30 susceptibility meter. This data release includes susceptibility measurements, processed gravity data, shapefiles with field locations, and site photos.
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New gravity and magnetic compilations and elevation-bathymetry models have been compiled for the Lake Superior region. These data provide continuous sets of observations for geologic interpretations spanning political boundaries such as US States and the US-Canada border where bedrock geology is largely concealed beneath glacial deposits and surface water. These data are providing constraints for on-going 3D geologic modeling of the Midcontinent Rift System and are helping to understand the metallogeny of the region.
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Gravity data were collected in 2016 and 2017 to assist in mapping subsurface geology in and around the eastern Adirondack highlands, northern New York, which host numerous iron-oxide apatite deposits. Many of these deposits contain rare-earth elements, which are considered a critical mineral resource. This data release provides principal facts for 189 new gravity stations that were acquired to fill in gaps in the existing public gravity data coverage.
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Surface geophysical surveys were conducted from 2016 to 2018 in the greater East River Watershed near Crested Butte Colorado with a focused effort in Redwell Basin as part of a broader study of the role of bedrock groundwater in the hydrogeology of mineralized mountain watersheds. Five electrical resistivity tomography (ERT) profiles were acquired within Redwell Basin and Brush Creek to map geologic structure at depths up to 40 meters, depending on the subsurface resistivity, using the Advanced Geosciences, Inc. SuperSting R8 resistivity meter. This data release includes the raw and processed resistivity data as well as inverted resistivity models. All are provided as digital data, and data fields for each file...
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The U.S. Geological Survey (USGS) collected gravity data in the Wet Mountains, CO from September 2021 to July 2022 to compliment newly collected airborne magnetic data for surface and subsurface geologic mapping. A total of 261 measurements were collected across two Ediacaran-Ordovician alkaline complexes (Gem Park and McClure Mountain) and gabbroic outcrops suspected Ediacaran-Ordovician in age. These data supplement existing public gravity data to aid the subsurface interpretation of mapped and concealed Ediacaran-Ordovician alkaline intrusions related to rare earth element (REE) mineralization.


    map background search result map search result map Updated aeromagnetic and gravity anomaly compilations and elevation-bathymetry models over Lake Superior Helicopter magnetic and gravity gradiometry survey over the Pea Ridge iron mine and surrounding area, southeast Missouri, 2014 Principal facts of gravity data in the southern San Luis Basin, northern New Mexico Physical Properties by Geologic Unit in the Southern San Luis Basin, New Mexico Crustal Architecture Beneath the Southern Midcontinent (USA) -- Data Grids and 3D Geophysical Models Crustal and upper mantle density model for the southern midcontinent Principal facts of regional gravity data in northeast Iowa Elevation surface grids for the southern midcontinent Principal facts of gravity data collected in and around the eastern Adirondack highlands, northern New York Surface electrical resistivity tomography, magnetic, and gravity surveys in Redwell Basin and the greater East River watershed near Crested Butte, Colorado, 2017 Gravity Data Magnetics Data Electrical Resistivity Tomography (ERT) Data Bouguer gravity and magnetic susceptibility measurements at Iliamna Volcano, Alaska 2019 Density and magnetic susceptibility measurements on Precambrian rocks in the Iron Mountain-Menominee region, Michigan-Wisconsin Principal facts of regional gravity data in the central Upper Peninsula, Michigan, and northeastern Wisconsin Principal facts of gravity data from the Stillwater Complex, Montana, 2013-2014 and 2020 Gravity data in the Wet Mountains area, southcentral Colorado, 2021 to 2022 Gravity data in the Wet Mountains area, southcentral Colorado, 2023 Airborne Geophysical Survey Inventory of the Conterminous United States, Alaska, Hawaii, and Puerto Rico (ver. 4.0, April 2023) (Under Revision) Gravity Data Magnetics Data Electrical Resistivity Tomography (ERT) Data Surface electrical resistivity tomography, magnetic, and gravity surveys in Redwell Basin and the greater East River watershed near Crested Butte, Colorado, 2017 Helicopter magnetic and gravity gradiometry survey over the Pea Ridge iron mine and surrounding area, southeast Missouri, 2014 Gravity data in the Wet Mountains area, southcentral Colorado, 2021 to 2022 Density and magnetic susceptibility measurements on Precambrian rocks in the Iron Mountain-Menominee region, Michigan-Wisconsin Principal facts of gravity data in the southern San Luis Basin, northern New Mexico Physical Properties by Geologic Unit in the Southern San Luis Basin, New Mexico Principal facts of regional gravity data in northeast Iowa Principal facts of regional gravity data in the central Upper Peninsula, Michigan, and northeastern Wisconsin Principal facts of gravity data from the Stillwater Complex, Montana, 2013-2014 and 2020 Bouguer gravity and magnetic susceptibility measurements at Iliamna Volcano, Alaska 2019 Updated aeromagnetic and gravity anomaly compilations and elevation-bathymetry models over Lake Superior Crustal Architecture Beneath the Southern Midcontinent (USA) -- Data Grids and 3D Geophysical Models Crustal and upper mantle density model for the southern midcontinent Elevation surface grids for the southern midcontinent Airborne Geophysical Survey Inventory of the Conterminous United States, Alaska, Hawaii, and Puerto Rico (ver. 4.0, April 2023) (Under Revision)