Geologic units in Greene county, Illinois

Carbondale Formation (Pennsylvanian (Moscovian to Kasimovian)) at surface, covers 36 % of this area

Carbondale Formation.

Meppen Limestone, Fern Glen Formation, and Burlington-Keokuk Limestone (Mississippian (Tourniaisian to Visean)) at surface, covers 24 % of this area

Meppen Limestone, Fern Glen Formation, and Burlington-Keokuk Limestone.

Tradewater Formation (Pennsylvanian (Bashkirian to Moscovian)) at surface, covers 11 % of this area

Tradewater Formation

Warsaw Formation and Salem Limestone (Mississippian (Visean)) at surface, covers 8 % of this area

Warsaw Formation and Salem Limestone in western Illinois.

Silurian System undivided (Silurian (Llandovery to Pridoli)) at surface, covers 6 % of this area

Silurian System undivided, includes Sexton Creek Limestone, St. Clair Limestone, and Moccasin Springs Formation in southern Illinois; includes Wilhelmi Formation, Elwood Dolomite, Kankakee Dolomite, Joliet Dolomite, Sugar Run Dolomite, and Racine Dolomite in northeastern Illinois; includes Mosalem, Tete des Morts, Blanding, Sweeney, Marcus, and Racine Dolomites in northwestern Illinois.

Shelburn-Patoka Formations undivided (Pennsylvanian (Kasimovian)) at surface, covers 6 % of this area

Shelburn-Patoka Formations undivided.

New Albany Shale, Blocher Shale, Sylamore Sandstone, Selmier Shale, Sweetland Creek Shale, Grassy Creek Shale, Saverton Shale, and Louisiana Limestone (Middle Devonian (Givetian) to Upper Devonian (Fammenian)) at surface, covers 5 % of this area

New Albany Shale, Blocher Shale, Sylamore Sandstone, Selmier Shale, Sweetland Creek Shale, Grassy Creek Shale, Saverton Shale, and Louisiana Limestone.

Glen Park Formation, Hannibal Shale, Chouteau Limestone, McCraney Limestone, Prospect Hill Siltstone, and Starrs Cave Limestone (Mississippian (Tourniaisian)) at surface, covers 3 % of this area

Glen Park Formation, Hannibal Shale, Chouteau Limestone, McCraney Limestone, Prospect Hill Siltstone, and Starrs Cave Limestone.

Maquoketa Formation or Group (Upper Ordovician (Stage 6 to Hirnatian)) at surface, covers 1 % of this area

Maquoketa Formation or Group, includes Cape Limestone, Cape La Croix Shale, Thebes Sandstone, Orchard Creek Shale, Girardeau Limestone, and Leemon Formation in southern Illinois; includes Scales Shale, Fort Atkinson Limestone, Brainard Shale, and Neda Formation in northern Illinois; includes Noix Oolite in western Illinois.

Muscatatuck Group (Middle Devonian (Eifelian to Givetian)) at surface, covers 0.6 % of this area

Muscatatuck Group, includes Grand Tower Limestone and St. Laurent (Alto and Lingle) Formation in southern Illinois; includes Detroit River Formation, Wapsipinicon Limestone, and Cedar Valley Limestone in northern and western Illinois.