Baraga Group; Michigamme Formation, undivided (WIXm;0)

Baraga Group; Michigamme Formation, undivided - Thick and stratigraphically varied formation of sedimentary and less abundant volcanic rocks. Metamorphosed graywacke is predominant rock of Michigamme Formation. Calcareous concretions common. Metamorphosed from cholorite to sillimanite grade (Cannon, 1986). Mapped undivided in poorly exposed areas

State	Wisconsin
Name	Baraga Group; Michigamme Formation, undivided
Geologic age	Early Proterozoic
Original map label	Xm
Comments	Continental margin assemblage (north of Niagara Fault). This unit description is a combination of descriptions for unit "Xm" [Michigamme Formation, undivided] and unit "Xmgs" [Michigamme Formation, metamorphosed graywacke] as originally published on the Sims (1992) map. Polygons identified on that paper map as "Xm" and "Xmgs" are combined under the single unit symbol "Xm" in this digital product. Reference: Cannon, W.C., 1986, Bedrock geologic map of the Iron River 1o x 2o quadrangle, Michigan and Wisconsin: U.S. Geological Survey Miscellaneous Investigations Series Map I-1360-B, scale= 1:250,000.
Primary rock type	graywacke
Secondary rock type
Other rock types
Lithologic constituents	Major Metamorphic > Metasedimentary > Metaclastic > Metasandstone > Metagraywackemetagraywacke
Map 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 [http://pubs.er.usgs.gov/publication/i2185]
Unit references	Cannon, W.C., 1986, Bedrock geologic map of the Iron River 1o x 2o quadrangle, Michigan and Wisconsin: U.S. Geological Survey Miscellaneous Investigations Series Map I-1360-B, scale= 1:250,000. [http://pubs.er.usgs.gov/publication/i1360B]
Geographic coverage	Florence - Forest - Iron - Marinette - Vilas