1. Hydrogeology of aquifers of Paleozoic age, upper Colorado River Basin-excluding the San Juan Basin-in Colorado, Utah, Wyoming, and Arizona Yale Public content 1989. 2002-06-01T04:00:00Z. 2002-06-01T04:00:00Z. Geological Survey (U.S.). The Survey ; For sale by Map Distribution. English. Public. Colorado River Watershed (Colo.-Mexico).