Maps, grids, and flight-line databases of a detailed aerial survey and maps and grids of satellite data

Spatial footprints with scientific and operational characteristics of airborne electromagnetic surveys conducted by or for the USGS.

Study to estimate the 3-D distribution of permafrost, to evaluate the effectiveness of these methods at mapping permafrost geometry, and to better define the physical properties of the subsurface in discontinuous permafrost areas.

Airborne electromagnetic and magnetic survey data were collected in 2017 along 347 line kilometers. Includes processed AEM and magnetic data and inverted resistivity depth sections. Data are provided in CSV format.

Airborne electromagnetic and magnetic survey data were collected during 2016 along 300 line kilometers in this area, flown at a nominal flight height of 30 m above terrain along widely spaced reconnaissance lines. Includes raw and processed AEM data, laterally-constrained inverted resistivity depth sections along all flight lines, and unprocessed and processed magnetic data. Data are provided in CSV format.

Airborne electromagnetic (AEM) and magnetic survey data along 1,637 line-km at a nominal flight height of 30m above terrain (averaging 53m), with nominal line spacing 1 km or 4 km. Data provided are minimally processed AEM and magnetic measurements, fully processed AEM data were used to develop an included resistivity model.

Airborne electromagnetic (AEM) and magnetic survey data, a total of 3065 line-kilometers, collected during October 2001 with line spacing 400m and nominal altitude of 30m. Includes raw and processed AEM data and magnetic data, in CSV format.

Airborne electromagnetic and magnetic survey data were collected during 2019 along 1,467 line-kilometers in this area. The survey was flown at a mean flight height of 140 meters (m) above terrain and line spacings ranging from 150 m to 600 m. Data are provided in CSV and shapefile formats.

Airborne electromagnetic (AEM) and magnetic survey data collected in 2015 along 769 line-kilometers including raw and processed AEM and magnetic data, processed AEM resistivity-depth inversions. Data are provided in CSV format.

Airborne electromagnetic and magnetic survey data were collected in 2014 in this area. The survey was flown at a nominal flight height of 30 m above terrain, line spacing of 200 m with a smaller area at 100 m. Includes raw and processed AEM data and spatially-constrained inverted resistivity depth sections, and unprocessed and processed magnetic data that has been drift corrected, leveled, and draped to terrain. Data are provided in CSV format.

Airborne electromagnetic and magnetic survey data in 2012 along 556 line-kilometers over this volcano flown at a nominal flight height of 30 meters (m) above terrain with a nominal spacing of 250 m. Data are provided in CSV and GeoTiff formats.

Airborne electromagnetic and magnetic survey data collected during 2021 over 3,170 line kilometers with nominal flight height of 30 - 40 m above terrain and nominal line spacing of 0.5 miles. Data are provided in Geosoft database, Geosoft grid, GeoTiff, Geosoft map, and netCDF formats.

Airborne electromagnetic and magnetic survey data collected during April and May 2019 along 1,467 line-kilometers in this area. Data are provided in netCDF format.

Airborne electromagnetic (AEM) and magnetic survey data to support groundwater salinity mapping and hydrogeologic framework development. Data are provided in CSV format.

Data from a helicopter-borne electromagnetic and magnetic survey flown over this area area in 2000. Nominal elevation of the sensor was 60 meters. Survey coverage comprises 1,914 line kilometers. Data are provided in CSV format.

Airborne electromagnetic (AEM) and magnetic survey data in this area to aid groundwater studies. Includes inverted resistivity model. Data are provided in CSV, plotted sections provided in PDF.

Airborne electromagnetic and magnetic survey data were collected during 2016 along 4,212 line-kilometers over this area. The survey was flown with a nominal line spacing of 450 meters or less, and mean flight height about 48 m providing depth of investigation about 500m. Data are provided in CSV format, flight lines in shapefile format.

Releases airborne survey data, resistivity cross-sections and depth slices derived from data inversion. Resulting resistivity models confirm geologic framework, constrain hydrostratigraphy and depth to basement, and reveal fault and fold distribution.

Gridded data used to revise base of aquifer, with supporting elevation data.

Airborne electromagnetic (AEM) and magnetic survey data were collected in 2016 along 4,212 line-kilometers over this area as part of a study of the subsurface geologic structure and geothermal and groundwater resources of Yellowstone National Park. Data are provided in CSV format.

Airborne electromagnetic, magnetic, and radiometric data were acquired in 2018-2019 along 16,816 line-kilometers flown at a nominal sensor flight height of 30 m above terrain with 6- to 12-kilometer spaced east-west flight lines to understand subsurface geologic structure and inform hydrologic models. Data are provided in CSV and GXF grid formats. Flight lines are provided in shapefile format.

Airborne electromagnetic, magnetic, and radiometric data were acquired from 2019 to 2020 along 24,030 line-kilometers over the Mississippi Alluvial Plain. Survey was flown at a nominal height of 120 m above terrain with 6-kilometer spaced east-west flight lines. Data are provided in ASEG-GDF2 format.

Airborne electromagnetic, magnetic, and radiometric data were acquired in 2018 along 2,364 line-kilometers in this area at anominal sensor flight height of 30 m above terrain with 250 to 1,000-meter spaced flight lines. Data are provided in GXF grid, CSV, and GeoTiff formats.

Airborne electromagnetic, magnetic, and radiometric data collected in 2017 over 1,984 line-kilometers in this area. Data include inverted resistivity and IP models as well. Data are provided in CSV format.

Grids and flight-line magnetic and conductivity data

Electrical resistivity results from two regional airborne electromagnetic surveys were combined to produce three-dimensional gridded models and derivative hydrogeologic products. This high-resolution information about hydrogeologic structure and properties to aid interpretations and hydrologic models. Data are provided in netCDF and GeoTiff formats.

This large producer of mercury operated from 1933 to 1971. As part of remediation work, this survey used electromagnetic methods to study subsurface resistivity.

Shallow soil characteristics were mapped using an electromagnetic sensor in October 2018. Data were acquired by towing the sensor on a wheeled cart behind an all-terrain vehicle (ATV), with the sensor at a height of 0.432 meters (m) above the ground surface. Data are provided in CSV format.

Ground-based transient electromagnetic data were acquired near Manistee National Forest, Michigan, to define the resistivity structure of the subsurface rocks.

The objective of the survey was to improve the understanding of the relationship between surface water and groundwater systems critical to developing management programs for water resources.

Flight line data, grids, and inversions for these surveys are intended to help understand shallow groundwater and develop groundwater resource plans for the aquifer.

Electrical resistivity depicted in georeferenced grids and maps, representing different approximate depths of investigation for each area. The range of subsurface investigation is comparable to the depth of shallow aquifers.

Geophysical surveys to map shallow hydrogeologic features of the southwestern part of the Sand Hills that contain a mix of fresh to saline lakes.

The objective of the contracted survey was to improve the understanding of the relation between surface water and groundwater systems critical to developing groundwater models used in management programs for water resources.

Grids, images, and flight-line paths for magnetic and resistivity surveys

Airborne geophysical data and a summary of the hydrologic application.

Flight-line and gridded data, with description of methodology and interpretation

Flight line data for an airborne magnetic survey with nominal sensor height of 60m above terrain, flight-line data for a gravity gradiometry survey, with a report containing instrument and procedure details. Data are provided in CSV format.

Study to help constrain 3-dimensional geologic maps of surficial materials in these glacial deposits

Describes electromagnetic sounding locations, data acquisition, calibration, and modeling; compares data to borehole data, correlating model results; and summarizes the applications and limitations of the TEM method. Examples of models are provided.

Time-domain electromagnetic (TEM) soundings were made in this area to map the location of a blue clay unit as well as suspected faults. Data are provided in CSV and shapefile formats.

Geophysical surveying data used to infer subsurface configuration of impermeable layers in this Pliocene-Pleistocene lake bed.

Compilation of airborne geophysical surveys (magnetic, radiometric, and electromagnetic) with links, for each survey to the data, metadata, and preview images. Includes a measure of quality indicating which surveys are likely most useful for investigations of subsurface mineral deposits. Data are provided in Esri file geodatabase, shapefile, and CSV formats.

Airborne surveys measuring the earth's magnetic field, resistivity or other electomagnetic properties, or gamma ray emission over parts of North America.

Three contractor reports and data files for an airborne electromagnetic survey describing data aquisition and processing. Processed geophysical data were inverted to produce resistivity depth sections along flight lines. Results are described herein.

Audio-magnetotelluric sounding data collected in 2017 in this area to understand geologic structure and lithologic variations.

Audiomagnetotelluric sounding data collected in 2018 in this area to understand subsurface geologic structure.

Audiomagnetotelluric station locations and data to characterize subsurface rock properties important for understanding surface water and groundwater quality issues, and also to improve knowledge of deep geologic structures that may have been conduits for hydrothermal fluids that formed mineral deposits.

Audiomagnetotelluric (AMT) sounding data collected in 2008 in this area in support of assessments of concealed mineral resources.

Geophysical study of the sediment under a river intended to help assess the susceptibility of this material to scour and the erosion of levees adjacent to the river.

A regional profile on the Utah-Nevada State line reveals a deeply penetrating, broad electrical conductor suggesting the southwestern limit of intact Archean crust is farther north than previously reported with implications for future mineral exploration.

Nevada is one of the Earth's premier gold producing regions, accounting for approximately 64 percent of the U.S and nine percent of the world total. The impact of these mines on nearby local economies and on our national balance of payments is profound, a

Surveys originally carried out by Soviet geophysicists from 1972 through 1974 were digitized. Georeferencing was problematic as were some of the measured characteristics; we explain what we did and how we have understood these data.

As part of a mineral resource assessment, imagery data were used to help target areas where exposed rocks might be hydrothermally altered, providing an indication of the location of potentially mineralized areas that may contain mineral deposits.

Data from seismic reflection and refraction, electromagnetic sounding, and resistivity profiling in a study area in Indiana. Exact location is not provided.

<h1>Introduction</h1>The San Juan-Silverton caldera complex located near Silverton, Colorado, in the Southern Rocky Mountains volcanic field is an ideal natural laboratory for furthering the understanding of shallow-to-deep volcanic-related mineral system

Chemical analyses of water and sediment samples, images depicting resistivity.

Uninterpreted geophysical measurements and geochemical and mineralogical analytical data from samples collected during the summer field seasons from 2007 to 2010. Data are available in a single Geographic Information System (GIS) database.

Data from more than 660 gravity stations, 100 line-km of truck-towed magnetometer traverses, and 260 physical-property sites in this area.

Shallow subsurface electrical conductivity mapped at selected U.S. Fish and Wildlife Service managed lands in northeast Montana and northwest North Dakota in the winters of 2017 and 2018. Data are provided in CSV format, locations are provided in shapefile format.

Electromagnetic, resistivity, and magnetic surveys used to determine the extent of contamination in an abandoned mine area.

Magnetotelluric soundings collected in 2019 to help inform depth-dependent fault zone geometry, fluid content and porosity in this part of the fault zone. Data are provided in MTH5 format.

The purpose of this report is to release one north-south and two east-west regional magnetotelluric sounding profiles collected where drillhole data are sparse. No interpretation of the data is included.

Magnetotelluric stations collected from 2015-2019 across parts of Minnesota, Wisconsin and the Upper Peninsula of Michigan to support regional investigations into the geologic and tectonic framework of the area and to support mineral resource investigations.

Magnetotelluric station data collected from 2016-2019 across parts of Missouri, Arkansas, Tennessee, Illinois, and Kentucky to support regional investigations into the geologic and tectonic framework of the area and mineral resource and geologic hazard investigations.

Magnetotelluric (MT) data from 65 stations collected in 2015 in this area create a regional conductivity model near the Mountain Pass mine.

Magnetotelluric data collected in 1989 and 1990 using USGS portable truck mounted systems that measure the distribution of electrical conductivity beneath the surface of the earth. This release provides digital information previously collected, recovered and reformatted for use with modern software. Data are provided in MT/EMAP formats.

Magnetotelluric sounding data collected in July 2018 in the Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field to understand the geologic structure of this area.

Magnetotelluric station locations and data intended to help to characterize subsurface rock properties important for understanding surface water and groundwater quality issues, and also to improve knowledge of deep geologic structures that may have been conduits for hydrothermal fluids that formed mineral deposits.

Magnetotelluric (MT) sounding data collected in 2003 along a north-south profile in this area to learn whether major mining districts in the Northern Nevada Gold Province are underlain by rocks of the Archean Wyoming craton, which are known to contain orogenic gold deposits, or by accreted rocks of the Paleoproterozoic Mojave province.

Magnetotelluric sounding data collected in 2006 in this area to improve understanding of the hydrogeology of the Santa Fe Group and the nature of the sedimentary deposits comprising the principal groundwater aquifers of the Rio Grande rift.

Magnetotelluric sounding data collected in 2003 along a north-south profile west of Wendover, Nevada, to understand the rocks underlying mineral deposits in this area.

Magnetotelluric sounding data collected in 2009 in this area to improve understanding of the hydrogeology of the Santa Fe Group and the nature of the sedimentary deposits comprising the principal groundwater aquifers of the Rio Grande rift.

Magnetotelluric (MT) sounding data collected in 2005 along an east-west profile in this area, to know whether major mining districts in the Northern Nevada Gold Province are underlain by rocks of the Archean Wyoming craton, which are known to contain orogenic gold deposits, or by accreted rocks of the Paleoproterozoic Mojave province.

Magnetotelluric sounding data collected in 2007 in this area to improve understanding of the hydrogeology of the Santa Fe Group and the nature of the sedimentary deposits comprising the principal groundwater aquifers of the Rio Grande rift.

Magnetotelluric sounding data collected in 2008 in this area to help USGS understand concealed mineral resources.

A standard for expressing the detailed information needed to properly describe data produced in this type of scientific investigation. Data are provided in CSV format.

Data from 102 magnetotelluric (MT) stations collected from 2012 through 2014 in this area to improve regional conductivity models of the western United States.

A study to investigate subsurface geologic conditions as they relate to ground-water flow in an abandoned landfill.

DC resistivity soundings were made to map subsurface lithologic, structural and hydrologic features important in controlling possible ground water contamination from mining activities and for design of remediation efforts.

Aeromagnetic surveys of South Carolina, merged to form seamless grids across the state. Gravity anomaly data are provided as well. Data provided in a variety of formats.

Data sets include drill-hole from core and geophysical logs, surface geology and elevation, and helicopter electromagnetic survey data. The model may be explored and .jpg or .tiff images or using specialized software provided.