This 30×60 minute map, provided as a digital GIS dataset only, is a 2022 compilation of the original 1989 USGS (Geologic map and cross sections of parts of the Grand Junction and Delta 30′ x 60′ quadrangles, west-central Colorado). This particular compilation includes both surficial and bedrock geodatabase sets. It was funded as part of a supplemental USGS STATEMAP program grant. Further details on the compilation process and provenance are available in the various metadata forms found in the package. The 30×60 minute map is a download package of GIS data only: no map plate or report. Digital ZIP download. OF-22-14D
From the map metadata:
The purpose of this dataset is to describe the surficial geologic setting of this 30×60 minute sheet. The original geologic map, USGS I-1825, was published in 1989 and included surficial units. The map was scanned and georeferenced. Digital Data Services digitized the map units, contacts, faults, geologic lines (including dikes and unconformities), and relative fault movement (shown as D on the down thrown side of the faults in the generic points feature class). The data was then imported into a GeMS style geodatabase. Topology was applied using the GeMS topology rules and then the gdb was validated using the GeMS validation script. The map was validated to Level 3.