Metabasalt (SDXb1;0)

Metabasalt

Dark-green amphibolite, actinolite schist, and greenstone. Interflow units consists of graphitic schist, chert, and carbonate- and silicate-facies iron-formation. Thickness of individual flows 50-400 ft (244-1,524 m).

State	South Dakota
Name	Metabasalt
Geologic age	Early Proterozoic
Lithologic constituents	Major Metamorphic > Metaigneous > Greenstone Metamorphic > Amphibolite Metamorphic > Schist > Amphibole-schistactinolite schist, graphitic schist Minor Sedimentary > Chemical > Chert Sedimentary > Chemical > Banded-iron-formation (Bed)
References	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	NGMDB product page for 72317
Counties	Custer - Lawrence - Pennington

Metabasalt

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.