Mafic metavolcanic rocks

Mafic metavolcanic rocks. Includes minor volcaniclastic and hypabyssal intrusive rocks metamorphosed to lower greenschist to lower amphibolite facies; includes the Ely Greenstone (~2,722 Ma).
State Minnesota
Name Mafic metavolcanic rocks
Geologic age Neoarchean
Lithologic constituents
Metamorphic > Metaigneous > Metavolcanic > Metabasalt (Greenschist, Amphibolite)mafic metavolcanic rocks
Metamorphic > Metaigneous > Greenstone (Greenschist, Amphibolite)includes the Ely Greenstone
Comments Part of the Supracrustal and hypabyssal intrusive rocks of the Wawa and Wabigoon subprovinces. Pre-D1 metavolcanic, metasedimentary, and hypabyssal intrusive rocks.

Jirsa, Mark A., Boerboom, Terrence J., Chandler, Val W., Mossler, John H., Runkel, Anthony C., and Setterholm, Dale R., 2011, S-21 Geologic Map of Minnesota-Bedrock Geology; Minnesota Geological Survey, State Map Series S-21. Scale 1:500,000.

NGMDB product
Counties Becker - Beltrami - Cass - Clay - Clearwater - Crow Wing - Grant - Hubbard - Itasca - Koochiching - Lake - Lake of the Woods - Lincoln - Mahnomen - Marshall - Norman - Otter Tail - Pennington - Polk - Red Lake - Roseau - Saint Louis - Todd - Traverse - Wadena - Wilkin