State | Wisconsin |
---|---|
Name | Menominee Group; Blair Creek Formation |
Geologic age | Early Proterozoic |
Lithologic constituents |
Major
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow)Dominantly dark-gray, massive, porphyritic tholeiitic basalt
Minor
Sedimentary > Chemical > Banded-iron-formation (Bed)
Metamorphic > Metasedimentary > Metaclastic > Metaconglomeratebasal metacomglomerate
|
Comments | continental margin assemblage (north of Niagara Fault) |
References | |
NGMDB product | |
Counties | Ashland - Iron - Vilas |