Intermediate Terraces
(Pleistocene) at surface, covers 67 % of this area Light gray to orange-brown clay, sandy clay, and silt; much sand and gravel locally.
Alluvium
(Holocene) at surface, covers 23 % of this area Gray to brownish gray clay and silty clay, reddish brown in the Red River Valley, some sand and gravel locally.
High Terraces
(Pleistocene) at surface, covers 6 % of this area Tan to orange clay, silt, and sand with a large amount of basal gravels.
Prairie Terraces
(Pleistocene) at surface, covers 3 % of this area Light gray to light brown clay, sandy clay, silt, sand, and some gravels.
Deweyville Terrace
(Pleistocene) at surface, covers 2 % of this area Gray mixed with brown-to-red clay and silty clay; some sand and gravel locally.
Alluvium
(Holocene) at surface, covers 0.3 % of this area Alluvium
Deweyville Formation
(Quaternary; Pleistocene and Holocene?) at surface, covers < 0.1 % of this area Deweyville Formation
