1:24,000-scale geologic mapping in the Clifton 7.5' quadrangle, in support of the USGS Colorado River/I-70 Corridor Cooperative Geologic Mapping Project, provides interpretations of the Quaternary stratigraphy and geologic hazards in this area of the Grand Valley. The Clifton 1:24,000 quadrangle is in Mesa County in western Colorado. Because the map area is dominated by various surficial deposits, the map depicts 16 different Quaternary units. Five prominent river terraces are present in the quadrangle containing gravels deposited by the Colorado River. The map area contains a large landslide deposit on the southern slopes of Mount Garfield. The landslide developed in the Mancos Shale and contains large blocks of the overlying Mesaverde Group. In addition, the landslide is a source of debris flows that have closed I-70 in the past. The major bedrock unit in the quadrangle is the Mancos Shale of Upper Cretaceous age. The map is accompanied by text containing unit descriptions, and sections on geologic hazards (including landslides, piping, gullying, expansive soils, and flooding), and economic geology (including sand and gravel). A table indicates what map units are susceptible to a given hazard. Approximately 20 references are cited at the end of the report.
Additional Publication Details
USGS Numbered Series
Geologic map of the Clifton Quadrangle, Mesa County, Colorado