This digital data release contains spatial datasets of bedrock geology, volcanic ash bed locations, test hole locations, bedrock outcrops, and structure contours of the top of bedrock and the base of the Ogallala Group from a previously published map (Souders, 2000). The GeologicMap feature dataset contains separate feature classes for the Ogallala Group map unit (ContactsAndFaults and MapUnitPolys) and the underlying pre-Ogallala bedrock map units (ContactsAndFaults_Bedrock and MapUnitPolys_Bedrock). The VolcanicAshBedPoints feature class contains the locations of volcanic ash beds within the Ogallala Group. The contours depicting the elevation of the top of bedrock (top of Ogallala Group where present and top of pre-Ogallala bedrock [...]