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National Geologic Map Database

Geologic Unit: Ivan

Usage:

Ivan Limestone [unranked] in Cisco Group (TX)
Ivan Limestone Member of Graham Formation of Cisco Group (TX*)
[?] Ivan Limestone of Graham Group (TX)
Incorrectly called Ivan Creek in some reports.


Geologic age:

Late Pennsylvanian (Virgilian)*


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

Not designated. Origin of name not stated by author, but probably named from Ivan, Stephens Co., TX (Plummer and Moore, 1922).


AAPG geologic province:

Bend arch*


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 ([ ]).