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The Keystone Thrust

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This page last updated on 05/22/2017
(Fig. 01)


Description: The Keystone Thrust System runs through the entire length of the Red Rock Canyon Park. It starts at the southwestern end of the 2,000 foot Sandstone Bluffs, also known as the Wilson Cliffs or the Red Rock Escarpment, and runs through the mountains behind Calico Basin (Fig. 02). It is composed dominantly of red and white Aztec Sandstone. Behind the sandstone there is a series of dark gray layers that rise above the Aztec Sandstone. This strata is limestone and dolomite, resulting with the older rocks resting upon the younger rocks. This process results from compressional forces within the Earth's crust, called a reverse fault. This is seen in a generalized cross section of the Sandstone Bluffs and the Wilson Cliffs thrust fault (Fig. 03). The two names were probably coined by James Wilson. He and his partner George Anderson owned a ranch at the base of the rugged cliffs rising to the west of the ranch, hence the Wilson Cliffs. The name of their ranch was called the "Sandstone Ranch," so they could be the ones who coined"Sandstone Bluffs" as well. The Keystone Thrust Fault is considered the most significant geological feature in Red Rock Canyon (Fig. 04). Fittingly, there is a hike in the Red Rock Canyon National Conservation Area called the Keystone Thrust Trail. This is an area where you can actually stand on the thrust fault. Click here for pictures and a description of this trail hike ... Keystone Thrust Trail - RRCNCA.


(Fig. 02)

(Fig. 03)

(Fig. 04)


Credits: Information and charts are from the publication, "Geologic Tours in the Las Vegas Area", published by the National Bureau of Mines and Geology