Menominee Group; Ironwood Iron-formation (MIXi;0)

Menominee Group; Ironwood Iron-formation

Interbedded cherty and slaty iron-formation. Locally, secondary enrichment has formed "soft ore" bodies. In eastern part of Gogebic Range, Ironwood Iron-formation is intercalated with pyroclastic rocks of Emperor Volcanic Complex, and in eastern half of T. 47 N., R. 43 W. (where mapped within unit Xip) consists entirely of black slate

State	Michigan
Name	Menominee Group; Ironwood Iron-formation
Geologic age	Early Proterozoic
Lithologic constituents	Major Sedimentary > Chemical > Banded-iron-formation (Bed)Interbedded cherty and slaty iron-formation. Locally, secondary enrichment has formed "soft ore" bodies. In eastern part of Gogebic Range, Ironwood Iron-fomration is intercalated with pyroclastic rocks of Emperor Volcanic Complex, and in eastern half of T. 47 N., R. 43 W. (where mapped within unit Xip) consists entirely of black slate Metamorphic > Metasedimentary > Metaclastic > SlateInterbedded cherty and slaty iron-formation. Locally, secondary enrichment has formed "soft ore" bodies. In eastern part of Gogebic Range, Ironwood Iron-fomration is intercalated with pyroclastic rocks of Emperor Volcanic Complex, and in eastern half of T. 47 N., R. 43 W. (where mapped within unit Xip) consists entirely of black slate
Comments	Continental margin assemblage (north of Niagara Fault)
References	Sims, P.K., 1992, Geologic map of Precambrian rocks, southern Lake Superior region, Wisconsin and northern Michigan: U.S. Geological Survey Miscellaneous Investigations Map I-2185, scale 1:500,000. https://pubs.er.usgs.gov/publication/i2185
NGMDB product	NGMDB product page for 10177 NGMDB product page for 71888 NGMDB product page for 71887
Counties	Gogebic

Menominee Group; Ironwood Iron-formation

Sims, P.K., 1992, Geologic map of Precambrian rocks, southern Lake Superior region, Wisconsin and northern Michigan: U.S. Geological Survey Miscellaneous Investigations Map I-2185, scale 1:500,000.