Gray to brownish gray clay and silty clay, reddish brown in the Red River Valley, some sand and gravel locally.
Tan to orange clay, silt, and sand with a large amount of basal gravels.
Light gray to brown liginitic clays with thin interbeds of limonitic sands or lignite; near base,calcareous, glauconitic, and fossiliferous beds may weather to black soil.
Light gray to light brown clay, sandy clay, silt, sand, and some gravels.
Gray to white sandstones; loose quartz sand, tuffaceous sandstone, volcanic ash, and brown sandy clays; petrified wood locally.
Light gray, tan and brown fine to coarse sand; some clay silt and gravel.
Brown to gray liginitic clays with thin interbeds of lignite or micaceous sands; calcareous shale, petrified wood, and bluish fossilferous clay locally.
Light gray to orange-brown clay, sandy clay, and silt; much sand and gravel locally.
Brown lignitic clays, silts and sands; some sideritic glauconite may weather to brown ironstone in lower part.
Gray and brown silt, silty clay, some very fine sand, reddish brown along the Red River.
Yellow to gray siltstones, sandstones, and clays with thin tuffaceous beds; some lenses of black chert gravel; petrified wood locally.
Gray calcareous clays which may weather to black soil; siltstone, taffaceous clays and some volcanic ash beds