White traces of early snow dust prominent sandstone and limestone rock layers on Mount Timpanogos and contrast with lower-elevation yellow-tinted aspen trees. The sedimentary rocks are the Pennsylvanian-age Bear Canyon Member of the Oquirrh Formation that have been transported eastward over 30 miles on thrust faults.
Mount Timpanogos, Wasatch Range, Utah County, Utah
Photographer: Jason Berry
Thousands of years of precipitation, wind, and glacial erosion have sculpted the east face of the Mount Timpanogos massif. The steep cliffs and snow-covered ledges of the Oquirrh Formation exposed on Roberts Horn (10,953 feet) are reminiscent of the Canadian Rockies.
GEOLOGIC MAP OF THE CHARLESTON QUADRANGLE, WASATCH COUNTY, UTAH
Robert F. Biek and Mike Lowe
The Charleston quadrangle lies on the south edge of a structural and topographic saddle between the Wasatch Range and Uinta Mountains. The quadrangle includes the southern part of Heber City and Heber Valley and the northern half of Round Valley, as well as parts of Deer Creek Reservoir and Wasatch Mountain State Park. The quadrangle also straddles the north edge of the Charleston-Nebo thrust plate, and thus includes three distinct groups of rocks: (1) a nearly complete section of Pennsylvanian rocks of the Oquirrh Formation that comprises the Charleston thrust plate; (2) underlying, southeast-dipping Jurassic and Triassic strata below the Charleston thrust; and (3) Upper Proterozoic, Cambrian, and Mississippian strata that are exposed in a structurally complicated zone between the Charleston thrust and Deer Creek detachment faults.
A variety of late Tertiary and Quaternary deposits record the evolution of the present landscape.
This geologic map and report provide basic geologic information necessary to further evaluate geologic hazards and resources in the area, and to gain an understanding of the geology upon which this landscape developed.
CD (28 p., 2 pl., 1:24,000)