Geology of the Canon City-Twin Mountain area, Fremont County, Colorado

Abstract

The Canon City-Twin Mountain area lies along the western edge of the Canon City Embayment. · Precambrian crystallines of the Wet Mountains and the Front Range bound the area on the west and northeast respectively. Sedimentary rocks of every geologic age except Cambrian, Silurian, Mississippian, and Triassic crop out in the area.

Two periods of strong deformation are recognized in the area,· the Pennsylvanian Ancestral Rocky Mountain orogeny and the Cretaceous-Tertiary Laramide orogeny. Uplift and minor faulting are the principal features of the Ancestral Rocky·Mountain orogeny; folding and high-angle thrust faulting are the common features developed during the Laramide orogeny. Tertiary and Quaternary-terraces record epeirogenic uplift which occurred after the end of the Laramide revolution.

Economic mineral products of the area include oil, coal, refractory sand, ornamental stone, flux lime, fire clay, and sand and gravel.