This geodatabase is a digital reproduction of three legacy USGS oil shale publications--MF-958 (Pitman and Johnson, 1978), MF-1069 (Pitman, 1979), and OC-132 (Pitman and others, 1990). The database consists of 106 feature classes in three feature datasets organized by publication. Each dataset contains isopach contours, isoresource contours, isoresource polygons, and corehole and drillhole locations with resource values for 12 kerogen-rich (R) and kerogen-lean (L) oil shale zones in the Piceance Creek Basin, Colorado. The uppermost zones, Mahogany and R-6, also contain detailed structure files. The zones in descending order are: Mahogany, R-6, L-5, R-5, L-4, R-4, L-3, R-3, L-2, R-2, L-1, and R-1.