Geologic units in Fulton county, Illinois

Carbondale Formation (Pennsylvanian) at surface, covers 58 % of this area: Carbondale Formation
Lithology: shale; limestone; clay or mud; sandstone; coal; black shale
Modesto Formation (Pennsylvanian) at surface, covers 5 % of this area: Modesto Formation
Lithology: shale; sandstone; limestone; clay or mud; coal; black shale
Abbott Formation (Pennsylvanian) at surface, covers 3 % of this area: Abbott Formation
Lithology: sandstone; shale; clay or mud; coal
Middle Valmeyeran (Salem, Warsaw, Borden, Springville; includes thin Mvl and Mk in south and east) Series (Mississippian) at surface, covers 0.9 % of this area: Middle Valmeyeran (Salem, Warsaw, Borden, Springville; includes thin Mvl and Mk in south and east) Series
Lithology: limestone; siltstone; shale
Lower Valmeyeran (Keokuk-Sedalia) Series (Mississippian) at surface, covers < 0.1 % of this area: Lower Valmeyeran (Keokuk-Sedalia) Series
Lithology: limestone; shale
Upper Valmeyeran (Aux Vases, Ste. Genevieve, St. Louis) Series (Mississippian) at surface, covers 2 % of this area: Upper Valmeyeran (Aux Vases, Ste. Genevieve, St. Louis) Series
Lithology: limestone; sandstone; dolostone (dolomite); sedimentary breccia; chert
Spoon Formation (Pennsylvanian) at surface, covers 31 % of this area: Spoon (includes Pa in northeast)
Lithology: shale; sandstone; clay or mud; limestone; coal; black shale