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Shawnee Group

Cyclic deposits with prominent limestone beds and thin shales; Topeka Formation at top and Oread Formation at base.
State Iowa
Name Shawnee Group
Geologic age Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgil]
Comments Approx thickness 220 ft.
Primary rock type limestone
Secondary rock type shale
Other rock types
Lithologic constituents
Major
Sedimentary > Carbonate > Limestone (Bed)
Sedimentary > Clastic > Mudstone > Shale (Bed)
Map references
Hershey H. G. 1969, Geologic Map of Iowa: Iowa Geological Survey, scale 1:500K
Unit references
Hershey H. G. 1969, Geologic Map of Iowa: Iowa Geological Survey, scale 1:500K
Counties Adair - Adams - Cass - Fremont - Madison - Montgomery - Page - Pottawattamie - Taylor - Union