Geology of the Indian Spring area, northern Washoe County, Nevada

Abstract

The Indian Spring study area is composed of Miocene volcanic and sedimentary rocks. Resting upon basal outcropping dacite are several units of the Canon Rhyolite. Sedimentary units lay unconformably upon the Canon Rhyolite. The Dome Rhyolite Series member of the Canon Rhyolite consists of ash flow tuffs and banded lava flows that form an extrusive dome. The dome was emplaced along a fault zone that parallels the regional fault pattern. The study area rhyolites are highly differentiated peralkaline rhyolites whose origin relates to the regional extensional tectonic setting in western Nevada. As such, they have a possible uranium deposit potential.