Named as upper member of the Huelster Formation; named for exposures on the Reynolds Ranch along the east side of Adobe Canyon, Jeff Davis Co, TX, Permian basin. No type locality designated. At Reynolds Ranch is composed of a single trachytic lava flow approximately 40 m thick; this flow forms rounded slopes and has a small percentage of anorthoclase set in dark-green aphanitic groundmass. The anorthoclase is up to 5 mm in diameter. Generally defined as silicic flows occurring in upper part of the formation below the Gomez Tuff. Geologic map. Chemical analyses. Correlation chart. Of Oligocene age.
Source: GNU records (USGS DDS-6; Denver GNULEX).
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