Data Release - Digital subsurface data from previously published contoured maps of the tops of the Mowry Shale, Morrison Formation, and Minnelusa Formation, Powder River basin, Wyoming and Montana

This digital data release contains previously published contours on the tops of the Mowry Shale, Morrison Formation, and Minnelusa Formation. The maps are from a series of U.S. Geological Survey Miscellaneous Field Studies (MF) showing computer-generated structure contours, isopachs, and cross sections of selected formations in the Powder River basin, Wyoming and Montana (Crysdale 1990, 1991a, 1991b). The maps were constructed from information stored in a U.S. Geological Survey Evolution of Sedimentary Basins data base. This data base contains picks of geologic formation and (or) unit tops and bases determined from electric resistivity and gamma-ray logs of 8,592 wells penetrating Tertiary and older rocks in the Powder River basin. [...]