This data release consists of 1,984 line-kilometers of airborne electromagnetic (AEM), magnetic data and radiometric data collected from October to November 2017 in the upper East River and surrounding watersheds in central Colorado. The U.S. Geological Survey contracted Geotech Ltd. to acquire these data as part of regional investigations into the geologic structure and hydrologic framework of the area. The AEM data have been inverted to produce a series of regional cross-sections that constrain the electrical properties of the subsurface to a depth of ~500m. Data were acquired using the VTEM ET time-domain helicopter-borne electromagnetic system along flight lines that cross important geological structures over a 483 square kilometer area. In addition to magnetic and radiometric data, this data release includes minimally processed AEM data, processed AEM data used in the development of resistivity and induced polarization (IP) models, and laterally constrained inverse models for resistivity and IP parameters along all flight lines. Data that intersected cultural infrastructure have been removed from the processed AEM data prior to inversion.

This data release consists of 1,984 line-kilometers of airborne electromagnetic (AEM), magnetic data and radiometric data collected from October to November 2017 in the upper East River and surrounding watersheds in central Colorado. The U.S. Geological Survey contracted Geotech Ltd. to acquire these data as part of regional investigations into the geologic structure and hydrologic framework of the area. The AEM data have been inverted to produce a series of regional cross-sections that constrain the electrical properties of the subsurface to a depth of ~500m. Data were acquired using the VTEM ET time-domain helicopter-borne electromagnetic system along flight lines that cross important geological structures over a 483 square kilometer area. In addition to magnetic and radiometric data, this data release includes minimally processed AEM data, processed AEM data used in the development of resistivity and induced polarization (IP) models, and laterally constrained inverse models for resistivity and IP parameters along all flight lines. Data that intersected cultural infrastructure have been removed from the processed AEM data prior to inversion. The data provided in this section include minimally processed (raw) AEM data and unprocessed and processed magnetic data. Digital data are described in the data dictionary and the complete data package from the contractor is included in a zip file and described in the contractor's report.

This data release consists of 1,984 line-kilometers of airborne electromagnetic (AEM), magnetic data and radiometric data collected from October to November 2017 in the upper East River and surrounding watersheds in central Colorado. The U.S. Geological Survey contracted Geotech Ltd. to acquire these data as part of regional investigations into the geologic structure and hydrologic framework of the area. The AEM data have been inverted to produce a series of regional cross-sections that constrain the electrical properties of the subsurface to a depth of ~500m. Data were acquired using the VTEM ET time-domain helicopter-borne electromagnetic system along flight lines that cross important geological structures over a 483 square kilometer area. In addition to magnetic and radiometric data, this data release includes minimally processed AEM data, processed AEM data used in the development of resistivity and induced polarization (IP) models, and laterally constrained inverse models for resistivity and IP parameters along all flight lines. Data that intersected cultural infrastructure have been removed from the processed AEM data prior to inversion. The data provided in this section include fully processed electromagnetic data produced from minimally-processed AEM data and used to develop inverted resistivity models. Digital data are described in the data dictionary and additional documentation is provided in the metadata.

This data release consists of 1,984 line-kilometers of airborne electromagnetic (AEM), magnetic data and radiometric data collected from October to November 2017 in the upper East River and surrounding watersheds in central Colorado. The U.S. Geological Survey contracted Geotech Ltd. to acquire these data as part of regional investigations into the geologic structure and hydrologic framework of the area. The AEM data have been inverted to produce a series of regional cross-sections that constrain the electrical properties of the subsurface to a depth of ~500m. Data were acquired using the VTEM ET time-domain helicopter-borne electromagnetic system along flight lines that cross important geological structures over a 483 square kilometer area. In addition to magnetic and radiometric data, this data release includes minimally processed AEM data, processed AEM data used in the development of resistivity and induced polarization (IP) models, and laterally constrained inverse models for resistivity and IP parameters along all flight lines. Data that intersected cultural infrastructure have been removed from the processed AEM data prior to inversion. The data provided in this section include fully processed electromagnetic data produced from minimally-processed AEM data and used to develop inverted resistivity models. Digital data are described in the data dictionary and additional documentation is provided in the metadata.

This data release consists of 1,984 line-kilometers of airborne electromagnetic (AEM), magnetic data and radiometric data collected from October to November 2017 in the upper East River and surrounding watersheds in central Colorado. The U.S. Geological Survey contracted Geotech Ltd. to acquire these data as part of regional investigations into the geologic structure and hydrologic framework of the area. The AEM data have been inverted to produce a series of regional cross-sections that constrain the electrical properties of the subsurface to a depth of ~500m. Data were acquired using the VTEM ET time-domain helicopter-borne electromagnetic system along flight lines that cross important geological structures over a 483 square kilometer area. In addition to magnetic and radiometric data, this data release includes minimally processed AEM data, processed AEM data used in the development of resistivity and induced polarization (IP) models, and laterally constrained inverse models for resistivity and IP parameters along all flight lines. Data that intersected cultural infrastructure have been removed from the processed AEM data prior to inversion.

This data release consists of 1,984 line-kilometers of airborne electromagnetic (AEM), magnetic data and radiometric data collected from October to November 2017 in the upper East River and surrounding watersheds in central Colorado. The U.S. Geological Survey contracted Geotech Ltd. to acquire these data as part of regional investigations into the geologic structure and hydrologic framework of the area. The AEM data have been inverted to produce a series of regional cross-sections that constrain the electrical properties of the subsurface to a depth of ~500m. Data were acquired using the VTEM ET time-domain helicopter-borne electromagnetic system along flight lines that cross important geological structures over a 483 square kilometer area. In addition to magnetic and radiometric data, this data release includes minimally processed AEM data, processed AEM data used in the development of resistivity and induced polarization (IP) models, and laterally constrained inverse models for resistivity and IP parameters along all flight lines. Data that intersected cultural infrastructure have been removed from the processed AEM data prior to inversion.

This data release consists of 1,984 line-kilometers of airborne electromagnetic (AEM), magnetic data and radiometric data collected from October to November 2017 in the upper East River and surrounding watersheds in central Colorado. The U.S. Geological Survey contracted Geotech Ltd. to acquire these data as part of regional investigations into the geologic structure and hydrologic framework of the area. The AEM data have been inverted to produce a series of regional cross-sections that constrain the electrical properties of the subsurface to a depth of ~500m. Data were acquired using the VTEM ET time-domain helicopter-borne electromagnetic system along flight lines that cross important geological structures over a 483 square kilometer area. In addition to magnetic and radiometric data, this data release includes minimally processed AEM data, processed AEM data used in the development of resistivity and induced polarization (IP) models, and laterally constrained inverse models for resistivity and IP parameters along all flight lines. Data that intersected cultural infrastructure have been removed from the processed AEM data prior to inversion. The data provided in this section include laterally-constrained inverted resistivity models and plotted depth sections along all flight lines. Digital data are described in the data dictionary and additional details regarding data inversion are described in the metadata processing steps.

This data release consists of 1,984 line-kilometers of airborne electromagnetic (AEM), magnetic data and radiometric data collected from October to November 2017 in the upper East River and surrounding watersheds in central Colorado. The U.S. Geological Survey contracted Geotech Ltd. to acquire these data as part of regional investigations into the geologic structure and hydrologic framework of the area. The AEM data have been inverted to produce a series of regional cross-sections that constrain the electrical properties of the subsurface to a depth of ~500m. Data were acquired using the VTEM ET time-domain helicopter-borne electromagnetic system along flight lines that cross important geological structures over a 483 square kilometer area. In addition to magnetic and radiometric data, this data release includes minimally processed AEM data, processed AEM data used in the development of resistivity and induced polarization (IP) models, and laterally constrained inverse models for resistivity and IP parameters along all flight lines. Data that intersected cultural infrastructure have been removed from the processed AEM data prior to inversion. The data provided in this section include fully processed electromagnetic data produced from minimally-processed AEM data and used to develop inverted resistivity models. Digital data are described in the data dictionary and additional documentation is provided in the metadata.

This data release provides digital flight-line and gridded data for a high-resolution airborne magnetic and radiometric survey over the region surrounding the Wet Mountains of southern Colorado, including parts of Custer and Fremont Counties. Data for this survey were collected by Sander Geophysics Limited International (SGL) under contract with the USGS. The survey was flown in June and July of 2021 using a helicopter equipped with a magnetometer mounted in a stinger extending from the nose of the aircraft and a gamma-ray spectrometer stowed onboard. The helicopter pilots followed pre-planned flight paths in a grid-like pattern, with east-west lines spaced 150 meters apart and north-south lines spaced 1,000 meters apart. A terrain clearance of 80 meters above ground could be realized in areas of low relief to maximize detection of gamma-rays, but higher clearances, as much as 200-500 meters, were required over rugged terrain and populated areas for safety reasons. A total of 17,032 kilometers were flown along the lines, covering a 2,200 square-kilometer irregular area. SGL performed extensive data processing after completion of flying and delivered the final data and report in February 2022.

This data release provides digital flight-line and gridded data for a high-resolution airborne magnetic and radiometric survey over the region surrounding the Wet Mountains of southern Colorado, including parts of Custer and Fremont Counties. Data for this survey were collected by Sander Geophysics Limited International (SGL) under contract with the USGS. The survey was flown in June and July of 2021 using a helicopter equipped with a magnetometer mounted in a stinger extending from the nose of the aircraft and a gamma-ray spectrometer stowed onboard. The helicopter pilots followed pre-planned flight paths in a grid-like pattern, with east-west lines spaced 150 meters apart and north-south lines spaced 1,000 meters apart. A terrain clearance of 80 meters above ground could be realized in areas of low relief to maximize detection of gamma-rays, but higher clearances, as much as 200-500 meters, were required over rugged terrain and populated areas for safety reasons. A total of 17,032 kilometers were flown along the lines, covering a 2,200 square-kilometer irregular area. SGL performed extensive data processing after completion of flying and delivered the final data and report in February 2022.