Geologic map of the Black Ridge quadrangle, Delta and Montrose Counties, Colorado
By: by Wallace R. Hansen.
Contributors: Geological Survey (U.S.)
Series: Geologic quadrangle map -- GQ-747.
Publisher: U.S. Geological Survey
Place of publication: Washington, D.C
Format: Map
Subjects: Geology -- Colorado -- Delta County -- Maps.; Geology -- Colorado -- Montrose County -- Maps.
Genres: Maps.
Other titles: Black Ridge quadrangle, Delta and Montrose Counties, Colorado.
Notes: Relief shown by contours and spot heights.

"Geology mapped by W.R. Hansen, 1965-66, assisted by J.J. Antony, J.B. Hansen, and E.E. McGregor."

Includes text, stratigraphic section, 3 cross sections, and quadrangle location diagram; latter diagram also on envelope.

"Datum is mean sea level."

"Base by U.S. Geological Survey, 1955."