The USGS had an aerial survey flown over parts of Cameron, Hidalgo, and Willacy Counties in Texas. The aerial survey included measurements of the earth's magnetic field and of the radioactivity of the surface rocks and soils.
This report presents the results of analyses and interpretation of aerial gamma-ray, Landsat TM, geologic, and digital elevation data of the Big Bend area in Texas.
Data generated by aerial sensing of radiation emanating from the earth's surface provides general estimates of the geographic distribution of Uranium, Thorium, and Potassium in surficial and bedrock units. Covers the conterminous United States, southeaste