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National Geologic Map Database

Geologic Unit: Carrizo

Usage:

Carrizo Sand (TX)
Carrizo Sand of Claiborne Group (AR*,LA*,TX*)
Carrizo Formation of Claiborne Group (LA)
Carrizo Formation of Wilcox Group (TX)


Geologic age:

early Tertiary (early Eocene)*


Type section, locality, area and/or origin of name:

Type exposure: in quarries about 0.5 mi west of Carrizo Springs, Dimmit Co., southern TX (Berry, 1922).
Plummer (1933) states these quarries are now thought to lie in base of the Reklaw and not in the original series of underlying sands defined as Carrizo. Geologists working in district agree that if a type locality is to be designated, it should be the exposure known as Brand Rock on Pena Creek west of Carrizo Springs.


AAPG geologic province:

Arkla basin*
East Texas basin*
Gulf Coast basin*
Ouachita folded belt*


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 ([ ]).