Till, Ground Moraine

Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by smooth, rolling terrain. Composite thickness of all Upper Wisconsin till may be up to 300 ft (91 m).
State South Dakota
Name Till, Ground Moraine
Geologic age Pleistocene-Upper Wisconsin
Lithologic constituents
Unconsolidated > Fine-detrital (Glacial-till)compact, silty, clay-rich matrix
Unconsolidated > Coarse-detrital (Glacial-till)sand to boulder-sized clasts of glacial origin

Martin, J.E., Sawyer, J.F., Fahrenbach, M.D., Tomhave, D.W., and Schulz, L.D., 2004, Geologic Map of South Dakota: South Dakota Geological Survey, GM 10, scale 1:500,000.

NGMDB product
Counties Corson - Dewey