Shakopee Formation of Prairie du Chien Group (IA,MN*,WI)
Shakopee Dolomite of Prairie du Chien Group (IL*,IA*,MI*,MN*,WI*)
Shakopee Dolomite of Knox Group (IL*-notably in southern part)
Shakopee Dolomite of Prairie du Chien Group of Knox Supergroup (IN-subsurface)
Willow River Member (IA) or Willow River Dolomite Member (MN*,WI*).
Early Ordovician (Ibexian; Stairsian to Cassinan)*
Type section: near town of Shakopee, Scott Co., MN (Stauffer, 1934).
Illinois basin*
Sioux uplift*
Wisconsin arch*
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 ([ ]).