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

State	Michigan
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	metasedimentary rock
Other rock types
Lithologic constituents	Major Metamorphic > Metasedimentary > Metaclastic > Metasandstone > Metagraywackemetagraywacke Sedimentary > Clastic > Mixed-clastic (Bed)Thick and stratigraphically varied formation of sedimentary and less abundant volcanic rocks. Minor Igneous > Volcanic (Bed)Thick and stratigraphically varied formation of sedimentary and less abundant volcanic rocks.
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] 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]
Geographic coverage	Baraga - Dickinson - Gogebic - Houghton - Iron - Marquette - Menominee - Ontonagon