Radiometric data collected from an uncrewed airborne system and via walking surveys at mine waste sites in New Mexico, 2024

Radiometric data (gamma ray spectrometry) were collected via a small uncrewed airborne system (sUAS) in June 2024 to characterize four distinct mine waste features in Southwestern New Mexico. Walking surveys with a handheld meter were also conducted over parts of the survey areas to provide ground truth checks for the airborne data. Survey sites and their respective areas covered include: the Blackhawk mine dump (~1200 m^2) and the Alhambra mine dump (21,000 m^2), both located in the Blackhawk Mining District, and the low-grade stock piles (2100 m^2) and the tailings (108,000 m^2) at the Copper Flat Mine. These data were collected in support of the U.S. Geological Survey (USGS) Earth Mapping Resources Initiative (Earth MRI), which aims to improve knowledge of the geologic framework of the United States through new geological and geophysical mapping and to identify areas that may have the potential to contain critical mineral resources. Data were acquired with the Medusa MS-350 radiometric sensor mounted on a PRISM Lite sUAS. Precise horizontal and vertical positions were obtained using an Emlid M2 differential GPS system. The nominal flying height for the surveys was 1-3 m. Data collected at heights above 3 m were removed in the final processing due to low signal-to-noise with increasing height, but remain in the raw data products. Data were processed to produce maps of Potassium (K), estimated Thorium (eTh), and estimated Uranium (eU).