Geologic map of Westwater 30' x 60' quadrangle, Grand and Uintah Counties, Utah and Garfield and Mesa Counties, Colorado (OFR-441dm)

By: J. L. Gualtieri

Data for the geologic map of the Westwater 30' x 60' quadrangle were derived from published mapping, principally that of Cashion. Rock unit contacts above the base of the Wasatch Formation were used as previously mapped and were cartographically modified to fit the topography of the Westwater base. Likewise, contacts of rock units below the Castlegate Sandstone or Blackhawk Formation were used as previously mapped by Cashion, but were slightly modified in the narrow belt of outcrops including the Dakota Sandstone. Mapping in the course of this project was restricted to that part of the section lying between the top of the Mancos Shale and the base of the Wasatch Formation.

The purpose of mapping undertaken in this project was to map the Sego Sandstone and the coal zones in the overlying Neslen Formation, which are shown on other larger-scale maps; the top of the Sego Sandstone is the datum used to correlate the coal zones.

Other Information:
Published: 1988 (digital 2004)
Plates: 4 pl.
Scale: 1:100,000
Location: Grand County and Uintah County