1. Geologic map of the northernmost Gore Range and southernmost Northern Park Range, Grand, Jackson, and Routt Counties, Colorado Yale Public content 1980. 2014-06-17T13:50:29Z. 2014-06-17T13:50:29Z. Snyder, George L. (George Leonard), 1927-. The Survey. English. Public. Colorado, Grand County, Jackson County, Routt County, U.S., Grand County., Jackson County., and Routt County.