Geologic units in Calhoun county, Arkansas

Terrace deposits (Late Pleistocene) at surface, covers 64 % of this area

Alluvial deposits on one or more terrace levels

Alluvium (Holocene) at surface, covers 28 % of this area

Alluvial deposits of present streams

Claibourne Group (Middle Eocene) at surface, covers 9 % of this area

Claibourne Group