Shakopee Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Ordovician
 ....Lower Ordovician
 .....Shakopee Formation
RTIowa
 Illinois
 Wisconsin
 Minnesota
 Prairie du Chien Group
SNIn Prairie du Chien Group. Overlies and interbedded with Root Valley Sandstone. N Illinois, Iowa, S Minnesota, and S Wisconsin.