No current usage.
(†Langdon Shale (IA,KS,MO,NE) replaced with Pillsbury Shale. See Pillsbury.)
Late Pennsylvanian (Virgilian)
Not synopsized to date.
not stated
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 ([ ]).