Peter L. Guth, 1990. "Chapter 11: Superposed Mesozoic and Cenozoic deformation, Indian Springs Quadrangle, southern Nevada", Basin and Range Extensional Tectonics Near the Latitude of Las Vegas, Nevada, Brian P. Wernicke
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Northwestern Clark County, Nevada, contains Tertiary extensional faults of the Sheep Range detachment that overprint the Mesozoic Sevier thrust belt. Three thrust faults occur: from west to east, the Spotted Range, Pintwater, and Gass Peak thrusts. The Spotted Range and Pintwater thrusts were minor imbrications in the thrust belt and have been excised by Tertiary extension. The Gass Peak thrust emplaced a major structural plate interpreted to have overridden a large ramp in the basal décollement of the Sevier belt, where the thrusts climb from the base of the Eocambrian clastic wedge to the middle Cambrian Bonanza King Formation.
Tertiary extension involved normal faults, steep at the surface but inferred to flatten into a deeper detachment; strike-slip faults that bound extensional blocks; and syntectonic sedimentary basins. The Spotted Range and Pintwater thrusts were largely excised by normal faults. The Dog Bone Lake fault is interpreted to have reactivated the basal thrust ramp, and other faults of the Sheep Range detachment may have reactivated the upper décollement in the Bonanza King Formation. Extensional faults are predominantly down to the west; they rotate bedding significantly in the eastern part of the region but much less to the west where the extensional allochthon was thicker and surficial extension less.