Geologic units in McLean county, Kentucky

Alluvium (Pleistocene to Holocene) at surface, covers 48 % of this area: Alluvium; includes glacial deposits along the Ohio River and its tributaries west of Cannelton locks
Lithology: sand; silt; glacial drift
Sturgis Formation (Middle to Upper Pennsylvanian) at surface, covers 37 % of this area: Sturgis Formation
Lithology: siltstone; sandstone; shale; limestone; coal
Tradewater Formation (Middle Pennsylvanian) at surface, covers 7 % of this area: Tradewater Formation
Lithology: siltstone; sandstone; limestone; coal
Caseyville Formation (Lower to Middle Pennsylvanian) at surface, covers 0.7 % of this area: Caseyville Formation
Lithology: siltstone; sandstone; conglomerate; shale; coal
Carbondale Formation (Middle Pennsylvanian) at surface, covers 8 % of this area: Carbondale Formation
Lithology: siltstone; sandstone; shale; coal