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National Geologic Map Database

Geologic Unit: Caddo

Usage:

No current usage.
(†Caddo Shale (AR) is same as Womble Shale. See Womble.)


Geologic age:

Middle to Late Ordovician (Whiterockian to Mohawkian)


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

[Notable exposures in Montgomery Co., southwestern AR.]


AAPG geologic province:

Ouachita folded belt


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 ([ ]).