1. Geologic map of the Casa Grande quadrangle, Colfax County, New Mexico and Las Animas County, Colorado Yale Public content 1969. 2012-02-27T16:03:29Z. 2012-02-27T16:03:29Z. Pillmore, C. L., 1930-. The Survey. English. Public. Colorado, Las Animas County, New Mexico, and Colfax County.