First published use. Authors state unit was named in unpublished thesis (Bernt, J., 1982, Univ of ID) for small valley in southeastern Owyhee Co, ID, Snake River basin. No type locality designated in this report. Unit is a welded ash-flow tuff consisting of a basal vitrophyre layer, 2-3 m thick, overlain by a pale-red to grayish-red lithoidal rhyolite layer with a 3-6 m thick lithophysal zone at base that contains 3-20 cm long gas cavities. Unit is exposed around margins of Browns Basin, located east of Sheep Creek canyon and occurs on west flank of Cottonwood Creek pluton; extends southward from these areas into NV. Thickness ranges up to 60 m. Overlies a thin layer of air-fall tuff, which, in turn, overlies Cedar Canyon tuff (new) of the Bieroth volcanics (redescribed). Underlies Whiskey Draw rhyolite (first used) and Cougar Point Tuff at various localities. Geologic map. Chemical analysis. Miocene? age.

Source: GNU records (USGS DDS-6; Denver GNULEX).