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National Geologic Map Database

Geologic Unit: Grayson

Usage:

Grayson Formation of Washita Group (TX* and LA-subsurface)
Grayson Marl of Washita Group (OK,TX*)
Grayson Shale of Washita Group (AR*,TX*, and LA*-subsurface)
Grayson Shale (TX* and LA*-subsurface)


Subunits:

(alphabetical): Carpenter Limestone Member (TX*), Eagle Mountains Sandstone Member (TX*), West Prong Lentil (TX).


Geologic age:

late Early to early Late Cretaceous (Albian to Cenomanian; Comanchean Provincial Epoch)*


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

Not synopsized to date.


AAPG geologic province:

Arkla basin*
East Texas basin*
Fort Worth syncline*
Ouachita folded belt*
South Oklahoma folded belt*
Strawn 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 ([ ]).