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Detailed mapping and stratigraphic and sedimentologic studies within thick sequences of Pennsylvanian and Permian strata of central Colorado show that most of the major faults called "Laramide" underwent significant displacements in the late Paleozoic. Abrupt eastward facies changes from fine- to coarse-grained sediments and from gray to red strata, and abrupt thinning of the section across the faults indicate that the north-northwest-trending Gore, Mosquito-Weston, Williams Range, and Elkhorn faults were offset as much as 8,000-9,000 ft during the deposition of the Minturn and Maroon strata during the Pennsylvanian and Permian Periods. The Hartsel uplift was faulted as much as 6,000-8,000 ft along its bounding, north-northwest-trending Agate Creek and Santa Maria faults, thereby splitting South Park into several local depositional basins during the Pennsylvanian and Permian.
Lithofacies evidence within Madera (Minturn) strata, and a Permian angular unconformity between the lower and upper members of the Sangre de Cristo Formation show that the north-northwest-trending Pleasant Valley fault was offset as much as 11,000 ft during the Pennsylvanian and Permian. Abrupt facies
changes within the Madera and Sangre de Cristo Formations, overlap of the Crestone Conglomerate onto Precambrian rocks, and the presence of unconformities within the late Paleozoic section indicate that several faults in the Crestone (Sangre de Cristo Range) and southern Wet Mountain areas were displaced significantly in the late Paleozoic.
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