Geologic units in Edgar county, Illinois

Shelburn-Patoka Formations undivided (Pennsylvanian (Kasimovian)) at surface, covers 41 % of this area

Shelburn-Patoka Formations undivided.

Bond Formation (Pennsylvanian (Kasimovian)) at surface, covers 40 % of this area

Bond Formation

Mattoon Formation (Pennsylvanian (Kasimovian)) at surface, covers 18 % of this area

Mattoon Formation.

Carbondale Formation (Pennsylvanian (Moscovian to Kasimovian)) at surface, covers 0.4 % of this area

Carbondale Formation.

Patoka and Shelburn Formations (Pennsylvanian) at surface, covers 0.1 % of this area

Mostly shale and sandstone; also includes thin beds of limestone and coal. WF, top of West Franklin member

Carbondale Group (Pennsylvanian) at surface, covers 0.1 % of this area

Mostly shale and sandstone; also includes thin beds of limestone, clay, and coal. S, Springfield Coal Member