Dark-green amphibolite and amphibolite schist. Thickness of individual flows 50-200 ft (15-61 m).
State South Dakota
Name Metabasalt
Geologic age Early Proterozoic to Late Archean ?
Lithologic constituents
Metamorphic > Amphibolite
Metamorphic > Schist > Amphibole-schist

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 Lawrence