Menominee Group; Blair Creek Formation

Dominantly dark-gray, massive, porphyritic tholeiitic basalt. Includes a basal conglomerate and a lean iron-formation in middle of formation
State Michigan
Name Menominee Group; Blair Creek Formation
Geologic age Early Proterozoic
Lithologic constituents
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow)
Sedimentary > Chemical > Banded-iron-formation (Bed)
Metamorphic > Metasedimentary > Metaclastic > Metaconglomerate
Comments Continental margin assemblage (north of Niagara Fault)
NGMDB product
Counties Gogebic - Ontonagon