Named as the upper member of the newly named Wristen Formation. Type section is the Wilshire Oil Co. 1 Atlantic Frame, sec 8, Blk 10 H and GN, Pecos Co, TX. Is entirely a subsurface unit. Identified in Winkler, Andrews, Ward, Pecos, Crane, Ector, and Upton Cos, TX, Permian basin. Conformably overlies Wink Member (newly named) of Wristen. Unconformably underlies Thirtyone Formation (newly named). Lies between 6,880 and 6,680 ft in the type well where it consists mostly of gray, calcareous to dolomitic shale, white to gray shaly limestone, and some gray dolomite, and white to gray chert. Becomes more calcareous to north. Thins north and south of type well. Cross sections. E-logs. Correlation chart. Graptolites of Niagaran age identified in upper 20 ft. Correlates with Henryhouse Formation, part of Fusselman, and part of Caballos Novaculite. Assigned to the Late Silurian.

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