Usage:
Francis Creek Shale Member of Carbondale Formation (IL)
Geologic age:
Pennsylvanian, Middle
Type section, locality, area and/or origin of name:
Roadcut on west side of Francis Creek, in NE/4 SW/4 sec. 22, T. 5 N., R. 1 E., Vermont quadrangle, Fulton Co., western central IL (Wanless, 1957).
AAPG geologic province:
Illinois basin
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 ([ ]).