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Mineral Resources On-Line Spatial Data

Devonian, undifferentiated

Devonian, undifferentiated: comprises Three Forks formation consisting of carbonaceous and calcareous shale with some sandstone and limestone, Jefferson limestone, and unnamed units of Devonian age.
StateMontana
NameDevonian, undifferentiated
Geologic agePhanerozoic | Paleozoic | Devonian
Original map labelDu
Primary rock typecarbonate
Secondary rock typefine-grained mixed clastic
Other rock typesconglomerate; sedimentary breccia; evaporite
Lithologic constituents
Major
Sedimentary > Clastic > Mixed-clastic > Siltstone-Mudstone (Bed)
Sedimentary > Carbonate (Bed)
Minor
Sedimentary > Clastic > Sedimentary-breccia (Bed)
Sedimentary > Clastic > Conglomerate (Bed)
Incidental
Sedimentary > Chemical > Evaporite > Anhydrite (Lense)
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
Ruppel, E.T., O'Neill, J.M., and Lopez, D.A., 1993, Geologic map of the Dillon 1o x 2o quadrangle, Idaho and Montana: U.S. Geological Survey Miscellaneous Investigations Series Map I-1803-H, scale 1:250,000.
O'Neill, J.M., Christiansen, R.L., 2002, Geologic map of the Hebgen Lake quadrangle: Montana Bureau of Mines and Geology Open File Report 464, 21 p, scale 1:100,000.
Lopez, D.A., 2001, Geologic map of the Sweet Grass Hills 30' x 60' quadrangle, north-central Montana: Montana Bureau of Mines and Geology Open File Report 443, 4 p., scale 1:100,000.
Wilson, A.B., and Elliott, J.E., 1997, Geologic maps of western and northern parts of Gallatin National Forest, south-central Montana: U.S. Geological Survey Geologic Investigations Series Map I-2584, 2 sheets, scale 1:126,720.
Mudge, M.R., Earhart, R.L., 1983, Geologic and structure maps of the Choteau 1° x 2° quadrangle, western Montana: United States Geological Survey Miscellaneous Geologic Investigations Series Map I-1300, scale 1:250,000.
Harrison, J.E., Whipple, J.W., and Lidke, D.J., 1998, Geologic map of the western part of the Cut Bank 1° x 2° quadrangle, northwestern Montana: U.S. Geological Survey Miscellaneous Geologic Investigations Series Map I-2593, scale 1:250,000.
Richards, P.W., 1955, Geology of the Bighorn Canyon-Hardin area, Montana and Wyoming: U.S. Geological Survey Bulletin 1026, 96 p., (incl. geologic map, scale 1:62,500).
Klepper, M.R., Weeks, R.A. and Ruppel, E.T., 1957, Geology of the southern Elkhorn Mountains, Jefferson and Broadwater Counties, Montana: U.S. Geological Survey Professional Paper 292, 82 p.
Lopez, D.A., 2000, Geologic map of the Bridger 30' x 60' quadrangle, Montana: Montana Bureau of Mines and Geology Geologic Map 58, scale 1:100,000.
Blackstone, D.L., Jr., 1975, Geology of the East Pryor Mountain quadrangle, Carbon County, Montana: Montana Bureau of Mines and Geology Special Publication 69, 13 p., 1 plate, scale 1:24,000.
Kellogg, K.S., and Williams, V.S., 2000, Geologic map of the Ennis 30' x 60' quadrangle, Madison and Gallatin Counties, Montana, Park County, Wyoming: U.S. Geological Survey Miscellaneous Geologic Investigations Series Map I-2690, scale 1:100,000.
Lonn, J., 2000, Geologic map of the Lima 30' x 60' quadrangle, southwest Montana: Montana Bureau of Mines and Geology Open File Report 408, 12 p., scale 1:100,000.
Richards, R.W., 1955, Geology of the Bighorn Canyon-Hardin area, Montana and Wyoming: U.S. Geological Survey Bulletin 1026, 93 p., 7 plates.
Sandberg, C.A. and Hammond, C.R., 1958, Devonian system in Williston basin and central Montana: American Association of Petroleum Geologists Bulletin, v. 42, no. 10, p. 2293-2334.
Hayes, M.D., 1985, Conodonts of the Bakken Formation, Williston basin, North Dakota: The Mountain Geologist, v. 22, no. 2, p. 64-77.
Sandberg, C.A. and Klapper, Gilbert, 1967, Stratigraphy, age, and paleotectonic significance of the Cottonwood Canyon Member of the Madison Limestone in Wyoming and Montana, in Contributions to general geology, 1967: U.S. Geological Survey Bulle
Sandberg, C.A., 1967, Exshaw Formation of Devonian and Mississippian age in northwestern Montana, in Hayes, P.T., Changes in stratigraphic nomenclature by the U.S. Geological Survey, 1966: U.S. Geological Survey Bulletin 1254-A, p. A39-A41.
Sando, W.J., 1982, New members of the Madison Limestone (Devonian and Mississippian), north-central Wyoming and southern Montana, in Stratigraphic notes, 1980-1982: U.S. Geological Survey Bulletin 1529-H, p. H125-H130.
Macke, D.L., 1993, Cambrian through Mississippian rocks of the Powder River basin, Wyoming, Montana, and adjacent areas, in Evolution of sedimentary basins--Powder River basin: U.S. Geological Survey Bulletin 1917-M, p. M1-M174
Sandberg, C.A., 1961, Widespread Beartooth Butte Formation of Early Devonian age in Montana and Wyoming and its paleogeographic significance: American Association of Petroleum Geologists Bulletin, v. 45, no. 8, p. 1301-1309.
McMannis, W.J., 1962, Devonian stratigraphy between Three Forks, Montana and Yellowstone Park, in The Devonian System of Montana and adjacent areas--Three Forks-Belt Mountains area and symposium: Billings Geological Society Guidebook, no. 13,
Sandberg, C.A., 1965, Nomenclature and correlation of lithologic subdivisions of the Jefferson and Three Forks Formations of southern Montana and northern Wyoming, in Contributions to stratigraphy: U.S. Geological Survey Bulletin 1194-N, p. N
Sloss, L.L., and Moritz, C.A., 1951, Paleozoic stratigraphy of southwestern Montana: American Association of Petroleum Geologists Bulletin, v. 35, no. 10, p. 2135-2169
McMannis, W.J., 1955, Geology of the Bridger Range, Montana: Geological Society of America Bulletin, v. 66, no. 11, p. 1385-1430.
Sandberg, C.A., and McMannis, W.J., 1964, Occurrence and paleogeographic significance of the Maywood Formation of Late Devonian age in the Gallatin Range, southwestern Montana, in Geological Survey research 1964: U.S. Geological Survey Profes
Sloss, L.L., and Laird, W.M., 1947, Devonian System in central and northwestern Montana: American Association of Petroleum Geologists Bulletin, v. 31, no. 8, p. 1404-1430.
Shank, S.G., and Eggler, D.H., 1991, Petrology and geochemistry of the Rocky Boy stock, Bearpaw Mountains, Montana--Evolution of shonkinite and monozite magmas, in Baker, D.W., and Berg, R.B., eds., Guidebook of the Central Montana Alkalic Province--Geol
Geographic coverageBeaverhead - Big Horn - Blaine - Broadwater - Carbon - Cascade - Deer Lodge - Flathead - Gallatin - Granite - Jefferson - Judith Basin - Lewis and Clark - Madison - Meagher - Park - Phillips - Pondera - Powell - Silver Bow - Stillwater - Sweet Grass - Teton - Wheatland

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