Prairie du Chien Group (IL*,IN*,IA*,MI*,MN*,OH*,WI*)
Prairie du Chien Group of Knox Supergroup (IN)
(alphabetical): Foster Formation (MI), Gunter Sandstone (IL), Oneota Dolomite/Formation (IN,IA*,IL*,MI*,MN*,WI*), Shakopee Dolomite/Formation (IN,IA*,IL*,MI*,MN*,WI).
Type area: exposures in vicinity of Prairie du Chien, WI (Bain, 1906).
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 ([ ]).