Usage:
Yegua Formation of Claiborne Group (LA,TX*)
Yegua Group (TX)
(USGS restricts Yegua Formation to TX; restored Cockfield Formation for use in LA, MS, and AR.)
Subunits:
GROUP STATUS (alphabetical) --all in TX: Bryan Sandstone, Cockfield Formation, Easterwood Shale, Smetana Sandstone.
FORMATION STATUS (alphabetical) --all in TX: Bryan Sandstone Member, Christine Member, Cistern Member, Creola Member, Dime Box Member, Jose Shale Member, La Perla Shale Member, Loma Blanca Tongue, Los Arrieros Shale Member, Mier Sandstone Member or Mier Sandstone Tongue.
Geologic age:
early Tertiary (middle Eocene)*
Type section, locality, area and/or origin of name:
Near mouth of Elm Creek, on [West] Yegua River [Creek], Lee Co., TX (Dumble, 1918).
AAPG geologic province:
East Texas basin*
Gulf Coast basin*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).
Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).