Airborne magnetic and radiometric survey, Laramie Mountains region, Wyoming, 2024-2025

This data release provides digital flight line data for a high-resolution airborne magnetic and radiometric survey over the Laramie Mountains region of Wyoming. The airborne survey was funded by the Earth Mapping Resources Initiative (Earth MRI). The survey was designed by the USGS in collaboration with the Wyoming State Geological Survey and contracted by the USGS. The survey was designed to meet complementary needs related to geologic mapping and characterization of mineral resource potential. A total of ca. 71,200 line km of magnetic and radiometric data were acquired over an area totaling ca. 12,600 km2 across two survey blocks. Data were collected from helicopters flown at a nominal terrain clearance of 100 meters (m) above topography along flight lines spaced at 200 m intervals. The flight lines were flown E-W in the southern block (A1+A2 block) and N-S in the northern block (A3+A4+A5 block). Tie lines were flown every 4000 m, perpendicular in direction to the regular flight lines. Data were collected by New-Sense Geophysics Ltd. and Merrick-Surdex Joint Venture, LLP under contract to the USGS using helicopters with magnetometers mounted in stingers and fully calibrated gamma-ray spectrometers. The survey operated out of airports in Laramie, Wheatland, Casper, and Douglas, Wyoming, from September of 2024 to September of 2025. Files that are available in this publication include flight line data for the magnetic and radiometric survey, and reports describing the survey parameters, field operations, quality control and data reduction procedures. A zip file is provided that contains the contractor's deliverable products that includes Geosoft databases and grids for the magnetic and radiometric survey and reports describing the survey and data reduction.