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National Geologic Map Database

Geologic Unit: Del Rio

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 usage by the U.S. Geological Survey. Other usages by state geological surveys.

"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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).