Tan to orange clay, silt, and sand with a large amount of basal gravels.
Gray to brownish gray clay and silty clay, reddish brown in the Red River Valley, some sand and gravel locally.
Light gray to light brown clay, sandy clay, silt, sand, and some gravels.
Gray to black clay of very high organic content, some peat.
Light gray to orange-brown clay, sandy clay, and silt; much sand and gravel locally.
Red sand and gravel and white clay; may be of Pliocene age; the formation mapped is equivalent to the Willis sand and does not include the terrace deposits, colluvium, and residuum commonly considered "Citronelle".
Green and bluish-green clay, sandy clay, and sand; gray siltstone and sand; locally fossiliferous.