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National Geologic Map Database

Geologic Unit: Shakopee

Usage:

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)


Subunits:

Willow River Member (IA) or Willow River Dolomite Member (MN*,WI*).


Geologic age:

Early Ordovician (Ibexian; Stairsian to Cassinan)*


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

Type section: near town of Shakopee, Scott Co., MN (Stauffer, 1934).


AAPG geologic province:

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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).