Mafic metavolcanic rocks

Dominantly tholeiitic basalt and basaltic andesite flows and tuffs; associated with sheet dikes, massive and layered metagabbro, and ultramafic rocks. In northeastern Wisconsin, rocks have been named the Quinnesec Formation.
State Michigan
Name Mafic metavolcanic rocks
Geologic age Early Proterozoic
Lithologic constituents
Major
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow, Pyroclastic-tuff)Dominantly tholeiitic basalt and basaltic andesite flows and tuffs; associated with sheet dikes, massive and layered metagabbro, and ultramafic rocks. In northeastern Wisconsin, rocks have been named the Quinnesec Formation.
Igneous > Volcanic > Mafic-volcanic > Basaltic-andesite (Flow, Pyroclastic-tuff)Dominantly tholeiitic basalt and basaltic andesite flows and tuffs; associated with sheet dikes, massive and layered metagabbro, and ultramafic rocks. In northeastern Wisconsin, rocks have been named the Quinnesec Formation.
Minor
Igneous > Plutonic > Ultramafic (Flow)Dominantly tholeiitic basalt and basaltic andesite flows and tuffs; associated with sheet dikes, massive and layered metagabbro, and ultramafic rocks. In northeastern Wisconsin, rocks have been named the Quinnesec Formation.
Metamorphic > Metaigneous > Metaintrusive > MetagabbroDominantly tholeiitic basalt and basaltic andesite flows and tuffs; associated with sheet dikes, massive and layered metagabbro, and ultramafic rocks. In northeastern Wisconsin, rocks have been named the Quinnesec Formation.
Comments Pembine-Wausau terrane
References
NGMDB product
Counties Dickinson - Iron - Menominee