Geologic units in Mississippi county, Missouri

Holocene series (Quaternary-Holocene Series) at surface, covers 100 % of this area

Alluvium - clay, silt, sand, and gravel.

Clayton Formation, Porters Creek Formation, Claiborne Formation, Wilcox Formation (Tertiary (Paleocene) to Tertiary (Pliocene)) at surface, covers 0.1 % of this area

Clayton and Porters Creek Formations; Claiborne and Wilcox Formations.

Alluvium (Pleistocene to Holocene) at surface, covers < 0.1 % of this area

Alluvium; includes glacial deposits along the Ohio River and its tributaries west of Cannelton locks