Paint River Group; Lower part (MIXpi;0)

State	Michigan
Name	Paint River Group; Lower part
Geologic age	Early Proterozoic
Original map label	Xpi
Comments	Continental margin assemblage (north of Niagara Fault). This unit is labeled "Xpl" on paper map of Sims (1992) but was changed to "Xpi" in digital file of Cannon et al. (1997). Description here is the same description as used for "Xpl" on paper map. Reference: James and others, 1968, Geology and ore deposits of the Iron River-Crystal Falls district, Iron County, Michigan: U.S. Geological Survey Professional Paper 570, 134 p.
Primary rock type	graywacke
Secondary rock type	iron formation
Other rock types	slate
Lithologic constituents	Major Metamorphic > Metasedimentary > Metaclastic > SlateIncludes Stambaugh Formation, Hiawatha Graywacke, Riverton Iron-formation, and Dunn Creek Slate (James and others, 1968). Sedimentary > Clastic > Sandstone > GraywackeIncludes Stambaugh Formation, Hiawatha Graywacke, Riverton Iron-formation, and Dunn Creek Slate (James and others, 1968). Sedimentary > Chemical > Banded-iron-formationIncludes Stambaugh Formation, Hiawatha Graywacke, Riverton Iron-formation, and Dunn Creek Slate (James and others, 1968).
Map references	Cannon, W.F., Kress, T.H., Sutphin, D.M., Morey, G.B., Meints, Joyce, and Barber-Delach, Robert, 1997, Digital Geologic Map and mineral deposits of the Lake Superior Region, Minnesota, Wisconsin, Michigan: USGS Open-File Report 97-455 (version 3, Nov. 1999), on-line only
Unit references	James and others, 1968, Geology and ore deposits of the Iron River-Crystal Falls district, Iron County, Michigan: U.S. Geological Survey Professional Paper 570, 134 pp. [http://pubs.er.usgs.gov/publication/pp570] 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	Iron