The digital geologic and geographic information system (GIS) data presented here were prepared to aid in Grand Mesa, Uncompahgre, Gunnison National Forest (GMUG) mineral resource assessment Project studies by the U.S. Geological Survey Mineral Resource Program. The goals of the GMUG Project is to provide mineral resource data and an assessment for undiscovered mineral resources in U.S. Forest Service (USFS) and Bureau of Land Management (BLM) lands in southwestern Colorado. The Project area covers a large region in southwestern Colorado that is bounded by latitudes 37o 45’ to 39o 30’ north and longitudes 106o to 109o west. The study area is covered by all or parts of six 1o x2o topographic and quadrangle geologic maps, which include geologic maps for the Leadville (Tweto and others, 1978), Montrose (Tweto and others, 1976), Durango (Steven and others, 1974), Grand Junction (Cashion, 1973), Moab (Williams, 1976), and Cortez (Haynes and others, 1972) quadrangles. These geologic maps were used inasmuch as a complete remapping and compilation effort for this study area was beyond the scope of the Project.
