Usage:
Del Rio Clay of Washita Group (TX*)
Del Rio Formation of Washita Group (TX*)
Del Rio Clay (NM,TX,Mexico)
Del Rio Formation (NM,TX)
Geologic age:
early Late Cretaceous (Cenomanian; Comanchean Provincial Epoch)*
Type section, locality, area and/or origin of name:
Named from Del Rio, Val Verde Co., southern TX (US geologic names lexicons, USGS Bull. 896, 1200).
Type locality: a conical butte, Loma de la Cruz, and surrounding clay lowlands, 2 mi south of Del Rio, [Val Verde Co., southern TX] (see Adkins, 1933).
AAPG geologic province:
Fort Worth basin*
Orogrande basin
Ouachita folded belt*
Permian 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 ([ ]).