Sandstone, chert and interbedded dolomite
Coarse - crystalline cherty dolomite with a basal Gunter Sandstone Member.
Fine crystalline, silty, cherty dolomite, and oolitic chert with local sandstone beds.
Eminence Dolomite - dolomite with some druse - coated chert. Potosi Dolomite - dolomite with abundance of druse - coated chert.
Pennsylvanian Undifferentiated
Keokuk Limestone, Burlington Limestone, Elsey Formation, Reeds Spring Formation, Pierson Limestone, Fern Glen Formation.