1. Geologic map of the Buckhorn Lakes quadrangle, Gunnison, Montrose, and Ouray Counties, Colorado Yale Public content 1987. 2012-07-05T15:32:03Z. 2012-07-05T15:32:03Z. Dickinson, R. G. (Robert G.). U.S. Geological Survey. English. Public. Colorado, Gunnison County, Montrose County, and Ouray County.