Bigford Formation of Claiborne Group (TX*)
Mills Bed (TX).
early Tertiary (middle Eocene)*
Named from Bigford Ranch, Webb Co., southern TX (Trowbridge, 1923).
Gulf Coast basin*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
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Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).