Gamma-ray, magnetic, and topographic data for parts of the Colorado Front Range

Online link http://geo-nsdi.er.usgs.gov/metadata/open-file/00-331/metadata.faq.html
Description Five geospatial grids from the NURE surveys, showing potassium, uranium, and thorium concentration, residual magnetic field, and digital elevation.
Originators Duval, Joseph S.; Reed, John C.; and Zietz, Isidore
Publication U.S. Geological Survey Open-File Report 00-331