1. Geologic and structure contour maps of the Raton 1/2⁰ x 1⁰ quadrangle, Colfax and Union counties, New Mexico and Las Animas County, Colorado [microform] Yale Public content 1990. 2002-06-01T04:00:00Z. 2002-06-01T04:00:00Z. Geological Survey (U.S.). U.S. Geological Survey : [Books and Open-File Report Section, distributor]. English. Public. New Mexico, Colfax County, Union County, Colorado, and Las Animas County.