Wallace formation (MTpCAw;0)

State	Montana
Name	Wallace formation
Geologic age	Proterozoic \| Mesoproterozoic
Original map label	pCw
Primary rock type	meta-argillite
Secondary rock type	carbonate
Other rock types	quartzite
Lithologic constituents	Major Metamorphic > Metasedimentary > Metaclastic > Argillite (Greenschist) Minor Metamorphic > Metasedimentary > Metaclastic > Quartzite (Greenschist) Sedimentary > Carbonate (Greenschist)Weakly metamorphosed limestone, dolomitic limestone, and dolomite.
Map references	Ross, P.R., Andrews, D.A., and Witkind, I.J., 1955, Geologic map of Montana: U.S. Geological Survey, 2 sheets, scale 1:500,000.
Unit references	Richards, P.W. and Rogers, C.P., Jr., 1951, Geology of the Hardin area, Big Horn and Yellowstone Counties, Montana: U.S. Geological Survey Oil and Gas Investigations Map OM-111, 2 sheets, scale 1:63,360 (Reprinted 1975). [http://pubs.er.usgs.gov/publication/om111] Lewis, R.S., 1998, Geologic map of the Montana part of the Missoula West 30' x 60' quadrangle: Montana Bureau of Mines and Geology Open File Report 373, 20 p, scale 1:100,000. Lonn, J.D., and McFadden, M.D., 1999, Geologic map of the Wallace 30' x 60' quadrangle: Montana Bureau of Mines and Geology Open File Report 388, 15 p., scale 1;100,000. Harrison, J.E., Griggs, A.B., and Wells, J.D., 1986, Geologic and structure maps of the Wallace 1° x 2° quadrangle, Montana and Idaho: Montana Bureau of Mines and Geology Montana Atlas Series 4-A, scale 1:250,000. Harrison, J.E., Cressman, E.R., and Whipple, J.W., 1992, Geologic and structure maps of Kalispell 1° x 2° quadrangle, Montana and Alberta, British Columbia: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-2267, scale 1:250,000. [http://pubs.er.usgs.gov/publication/i2267] Harrison, J.E., 1972, Precambrian Belt basin of northwestern United States--Its geometry, sedimentation and copper occurrences: Geological Society of America Bulletin, v. 83, no. 5, p. 1215-1240. Whipple, J.W., Connor, J.J., Raup, O.B., and McGimsey, R.G., 1984, Preliminary report on the stratigraphy of the Belt Supergroup, Glacier National Park and adjacent Whitefish Range, Montana, in McBane, J.D., and Garrison, P.B., eds., Northwest Montana an Harrison, J.E., 1984, Stratigraphy and lithocorrelation of the Wallace Formation, in Hobbs, S.W., ed., The Belt--Abstracts with summaries, Belt Sympsium II, 1983: Montana Bureau of Mines and Geology Special Publication 90, p. 24-26.
Geographic coverage	Flathead - Lake - Lincoln - Mineral - Missoula - Sanders