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National Geologic Map Database

Geologic Unit: Brad

Usage:

Brad Formation of Canyon Group (TX*)
(†Brad Formation not used by TX Geol. Survey. Rocks reallocated to Ranger Limestone and Ventioner Formation of Canyon Group. See also Ranger and Ventioner.)


Subunits:

FORMATION STATUS (alphabetical) --all in TX: Placid Shale Member*, Ranger Limestone Member*, Seaman Ranch Shale Member, Ventioner Beds.


Geologic age:

Late Pennsylvanian (Missourian)*


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

Named from town of Brad in Palo Pinto Co., Brazos River region, TX (Plummer and Moore, 1922).


AAPG geologic province:

Bend arch*
Fort Worth syncline*


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 ([ ]).