Named as a member of Vermejo formation of Montana group for Rail Canyon, T29N, R21E, Colfax Co, NM in the Las Vegas-Raton basin. No type locality designated. Occurs near the middle of the Vermejo above and beneath unnamed sandstone and shale. Lower contact is an unconformity. Lies 10-50+ ft above base of Vermejo in measured sections. Consists of white, massive, cross-bedded sandstone ranging from a few ft to 50 ft thick. Several measured sections show it as 8 to 35 ft thick. Has numerous inclusions of clay balls. Some beds are friable. Forms the roof of many mines. Of Late Cretaceous age. Cross sections.
Source: GNU records (USGS DDS-6; Denver GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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