Geologic units in Pope county, Illinois

Upper Pope Group (Tar Springs Sandstone through Kinkaid Limestone) (Mississippian (Serpukhovian)) at surface, covers 28 % of this area

Upper Pope Group (Tar Springs Sandstone through Kinkaid Limestone).

Tradewater Formation (Pennsylvanian (Bashkirian to Moscovian)) at surface, covers 24 % of this area

Tradewater Formation

Lower Pope Group (Aux Vases Sandstone through Glen Dean Limestone) (Mississippian (Visean)) at surface, covers 24 % of this area

Lower Pope Group (Aux Vases Sandstone through Glen Dean Limestone).

Caseyville Formation (Pennsylvanian (Bashkirian)) at surface, covers 14 % of this area

Caseyville Formation

Cretaceous undivided (Upper Cretaceous (Campanian to Maastrichtian)) at surface, covers 6 % of this area

Cretaceous undivided, includes Post Creek (Tuscaloosa), McNairy, and Owl Creek Formations (southern Illinois).

St. Louis Limestone (Mississippian (Visean)) at surface, covers 3 % of this area

St. Louis Limestone.

Ste. Genevieve Limestone (Mississippian (Visean)) at surface, covers 0.3 % of this area

Ste. Genevieve Limestone.

Permian ultramafic intrusions (Permian) at surface, covers < 0.1 % of this area

Permian ultramafic intrusions.