Named as lowest member (of 8 named members) of Schoonover Formation (new) for exposures on hilltop south of Dorsey Creek, northern Independence Mountains area, Bull Run quad, Elko Co, NV. Shown on geologic map of portions of Bull Run and Wildhorse quads. Consists of two contrasting facies grading laterally into one another. One is series of thin-bedded siliceous argillaceous lutites with thin chert units and some quartzose silt beds. Second facies is dominantly volcanic, consisting of successive flows and local agglomerates. Closely folded; estimated thickness is 650 ft. Overlies unnamed member; underlies Fry Creek Member (new) (Schoonover Formation). Contains fossils considered to be Mississippian age.

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

Sample of radiolarian chert from Mikes Creek/Dorsey Creek Member of Schoonover Formation collected at 41 deg 31.21'N, 116 deg 0.302'W, yielded Late Mississippian age. "Because of structural complexity of Schoonover sequence it is not known whether ages of the ribbon-chert packages also represent the age span of pebble conglomerate, quartzose arenite, volcanogenic sedimentary, and rare silty-limestone units that are intercalated with the chert in the lower part of the sequence."

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