From late Precambrian to Late Devonian time, shallow-water carbonate strata were deposited on a broad continental shelf along the west margin of North America in a region that is now the Great Basin. This deposition created a wedge of sedimentary rocks, the Cordilleran miogeocline, that thickens from about 1,000 m in cratonic areas in central Utah to nearly 10,000 m in central Nevada. Abrupt facies changes along the west margin of the miogeocline reflect depositional provinces from outer continental shelf to continental slope. Farther west in the Great Basin, coeval rocks consist mainly of shale, radiolarian chert, quartzite, and mafic pillow lava, considered to be mainly deep-water oceanic deposits.

Depositional provinces of the Great Basin were markedly changed by the Antler orogeny during Late Devonian and Early Mississippian time. This orogeny created the Antler highland, an upland belt trending north-northeast through central Nevada, along the former edge of the continental shelf. During Mississippian, Pennsylvanian, and Permian time, the Antler highland was either emergent or the depositional site of thin shallow-marine or continental coarse detrital sediments and shallow-marine carbonate. A foreland basin east of the Antler highland received thick deposits of coarse, chert-rich detritus during Mississippian and, to a lesser extent, Pennsylvanian and Permian time. A shallow-water carbonate shelf lay east of the foreland basin. Mississippian, Pennsylvanian, and Permian rocks est of the Antler highland consist of shale, sandstone, conglomerate, radiolarian chert, silty limestone, and mafic lava, all deposited in a deep-water oceanic environment.

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