Structure, Volcanic Stratigraphy, & Ore Deposits of the Pah Rah Range, Washoe County, Nevada: Olinghouse Mine, Pyramid Mining District, Perry Canyon Caldera, & Pah Rah Range Oligocene-Miocene Volcanic Succession

The Pah Pah Range nicely illustrates the interplay between Cenozoic magmatism, structure, and mineral deposits in western Nevada. Cenozoic magmatism has been nearly continuous from ~31 Ma to the present but has varied considerably in location, composition, and eruptive style. Fundamentally, magmatism has occurred in three distinct episodes. Volcanic rocks from 31 to about 23 Ma are almost entirely rhyolitic ash-flow tuffs erupted from large calderas, only one of which has been positively identified in the Pah Rah Range to date.