Skip to main content
SpringerLink
Log in

Tectonic setting of Au-Ag deposits hosted by Proterozoic strata along the Lewis and Clark line, west-central Montana

  • Chapter
Basement Tectonics 8

Part of the book series: Proceedings of the International Conferences on Basement Tectonics ((ICBT,volume 2))

  • 617 Accesses

Abstract

The Lewis and Clark line is a major lineament trending WNW from central Montana to the Coeur d’Alene mining district of northern Idaho. The Lewis and Clark line consists mainly of Cretaceous to Tertiary thrusts and steep strike-slip and dip-slip faults that are partly superimposed on Middle Proterozoic growth faults related to extension of the western continental margin.

Lode Au-Ag deposits are clustered along the Lewis and Clark line in the Big Belt uplift and comprise the Confederate Gulch, York, and Beaver Creek mining districts. These lodes are mostly epigenetic quartz veins with minor sulfides and are hosted by the Greyson Shale and Newland Limestone (of the Middle Proterozoic Belt Supergroup) and dioritic intrusions. Some mineralization, along bedding planes in the Greyson and Newland formations, may be synsedimentary or syndiagenetic, however. At least 2,581 kg (83,000 oz) Au were produced from lodes and 28,612 kg (920,000 oz) Au from placers locally derived from similar lodes. The average Au:Ag ratio for lodes is ≈ 1.5:1. Most lode Au occurrences along the Lewis and Clark line in the Big Belt uplift are interpreted to be remobilized from Archean basement rocks and deposited in Belt strata, in some cases syngenetically, near basement growth faults active during deposition of the Greyson and Newland formations. Metals were probably transported by aqueous solutions along faults. Au was probably remobilized during widespread but volumetrically minor magmatism in the Late Proterozoic and again in the Cretaceous-Tertiary.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Log in via an institution
Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 169.00
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 219.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info
Hardcover Book
USD 219.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Similar content being viewed by others

References

  • Baitis, H. W., 1988, York-A Proterozoic “shale”-hosted gold system in Montana [abstract]: Abstracts of the 94th Annual Convention of the Northwest Mining Association, Spokane, Washington, USA, p. 7.

    Google Scholar 

  • Billingsley, P., and A. Locke, 1941, Structure of ore districts in the continental framework: American Institute of Mining and Metallurgical Engineers Transactions, v. 144, p. 9–64.

    Google Scholar 

  • Catanzaro, E. J., and J. L. Kulp, 1964, Discordant zircons from the Little Belt (Montana), Beartooth (Montana), and Santa Catalina (Arizona) Mountains: Geochimica et Cosmochimica Acta, v. 28, p. 87–124.

    Article  Google Scholar 

  • Daniel, F., and R. B. Berg, 1981, Radiometric Dates of Rocks in Montana: Montana Bureau of Mines and Geology, Bulletin 114, 136 p.

    Google Scholar 

  • Garlick, W. G., 1987, Genesis of the Spar Lake strata-bound copper-silver deposit, Montana, Part I: Controls inherited from sedimentation and preore diagenesis — A discussion: Economic Geology, v. 82, p. 1967–1971.

    Article  Google Scholar 

  • Godlewski, D. W., and G. A. Zieg, 1984, Stratigraphy and depositional setting of the Precambrian Newland Limestone; pp. 2–4 in S. W. Hobbs (ed.), The Belt: Abstracts with Summaries — Belt Symposium II, 1983: Montana Bureau of Mines and Geology, Special Publication 90, 117 p.

    Google Scholar 

  • Harrison, J. E., 1972, Precambrian Belt basin of northwestern United States: Its geometry, sedimentation, and copper occurrences: Geological Society of America Bulletin, v. 83, p. 1215–1240.

    Article  Google Scholar 

  • Harrison, J. E., and M. W. Reynolds, 1976, Western U.S. continental margin: A stable platform dominated by vertical tectonics in the late Precambrian [abstract]: Geological Society of America Abstracts with Programs, v. 8, p. 905.

    Google Scholar 

  • Harrison, J. E., A. B. Griggs, and J. D. Wells, 1974, Tectonic Features of the Precambrian Belt Basin and Their Influence on Post-Belt Structures: U.S. Geological Survey, Professional Paper 866, 15 p.

    Google Scholar 

  • Hayes, T. S., and M. T. Einaudi, 1986, Genesis of the Spar Lake strata-bound copper-silver deposit, Montana: Part I, Controls inherited from sedimentation and preore diagenesis: Economic Geology, v. 81, p. 1899–1931.

    Article  Google Scholar 

  • Hershey, O. H., 1916, Origin and Distribution of Ore in the Coeur d’Alene Mining District: Washington Mining Scientific Press, Spokane, Washington, USA, 32 p.

    Google Scholar 

  • Himes, M. D., F. T. Bourns, H. C. Golden, J. A. Perello, S. A. Taylor, R. J. Winder, P. W. Rankin, S. Jennings, and G. A. Zieg, 1988, The Sheep Creek project, a Proterozoic sediment-hosted massive sulfide deposit, Meagher County, Montana [abstract]: Abstracts of the 94th Annual Convention of the Northwest Mining Association, Spokane, Washington, USA, p. 17.

    Google Scholar 

  • Hobbs, S. W., A. B. Griggs, R. E. Wallace, and A. B. Campbell, 1965, Geology of the Coeur d’Alene District, Shoshone County, Idaho: U.S. Geological Survey, Professional Paper 478, 139 p.

    Google Scholar 

  • James, H. L., and C. E. Hedge, 1980, Age of the basement rocks of southwest Montana: Geological Society of America Bulletin, v. 91, p. 11–15.

    Article  Google Scholar 

  • Johnson, E. A., 1973, Geology and Gold Deposits of the Confederate Gulch-White Gulch Area, Broadwater County, Montana: MS thesis, Montana College of Mineral Science and Technology, Butte, Montana, USA, 53 p.

    Google Scholar 

  • Knopf, A., 1963, Geology of the Northern Part of the Boulder Bathylith and Adjacent Area, Montana: U.S. Geological Survey, Miscellaneous Geologic Investigations Map 1-381, scale 1:48,000.

    Google Scholar 

  • Koschmann, A. H., and M. H. Bergendahl, 1968, Principal Gold-Producing Districts of the United States: U.S. Geological Survey, Professional Paper 610, 283 p.

    Google Scholar 

  • Lange, I. M., and R. A. Sherry, 1983, Genesis of the sandstone (Revett) type of copper-silver occurrences in the Belt Supergroup of northwestern Montana and northeastern Idaho: Geology, v. 11, p. 643–646.

    Article  Google Scholar 

  • Leach, D. L., G. P. Landis, and A. H. Hofstra, 1988, Metamorphic origin of the Coeur d’Alene base-and precious-metal veins in the Belt basin, Idaho and Montana: Geology, v. 16, p. 122–125.

    Article  Google Scholar 

  • Lorenz, J. C., 1984, The function of the Lewis and Clark fault system during the Laramide orogeny; pp. 221–230 in 1984 Guidebook, Northwestern Montana: Montana Geological Society, Billings, Montana, USA.

    Google Scholar 

  • McClernan, H. G., 1969, Geology of the Sheep Creek Area, Meagher County, Montana: MS thesis, Montana College of Mineral Science and Technology, Butte, Montana, USA, 75 p.

    Google Scholar 

  • ___, 1980, Metallogenic Map of the White Sulphur Springs Quadrangle, Central Montana: Montana Bureau of Mines and Geology, Geologic Map 7, scale 1:250,000.

    Google Scholar 

  • ___, 1983, Metallic Mineral Deposits of Lewis and Clark County, Montana: Montana Bureau of Mines and Geology, Memoir 52, 73 p.

    Google Scholar 

  • ___, 1984, Gold deposits of the Big Belt Mountains: Montana Bureau of Mines and Geology Bulletin, v. 121, p. 33–40.

    Google Scholar 

  • McGrew, L. W., 1977, Geologic Map of the Sixteen Quadrangle, Gallatin and Meagher Counties, Montana: U.S. Geological Survey, Geologic Quadrangle Map GQ-1383, scale 1:24,000.

    Google Scholar 

  • McMannis, W. J., 1959, Salient tectonic features of western Montana; pp. 71–75 in GSA Rocky Mountain Section: Guidebook to Field Trips: Geological Society of America, Boulder, Colorado, USA.

    Google Scholar 

  • ___, 1963, LaHood Formation — A coarse facies of the Belt Series in southwestern Montana: Geological Society of America Bulletin, v. 74, p. 407–436.

    Article  Google Scholar 

  • Marvin, R. F., and S. W. Dobson, 1979, Radiometric ages: Compilation B: U.S. Geological Survey, Isochron/West, no. 26, p. 3–32.

    Google Scholar 

  • Nesbitt, B. E., 1988, Gold deposit continuum: A genetic model for lode Au mineralization in the continental crust: Geology, v. 16, p. 1044–1048.

    Article  Google Scholar 

  • Pardee, J. T., and F. C. Schrader, 1933, Metalliferous Deposits of the Greater Helena Mining Region, Montana: U.S. Geological Survey, Bulletin 842, 318 p.

    Google Scholar 

  • Price, R. A., 1984, Tectonic setting of the Purcell (Belt) rocks of the southeastern Canadian Cordillera and adjacent parts of the United States; pp. 47–48 in S. W. Hobbs (ed.), The Belt: Abstracts with Summaries — Belt Symposium II, 1983: Montana Bureau of Mines and Geology, Special Publication 90, 117 p.

    Google Scholar 

  • Reed, G. C., 1951, Mines and Mineral Deposits (Except Fuels), Broadwater County, Montana: U.S. Bureau of Mines, Information Circular 7592, 62 p.

    Google Scholar 

  • Reid, R. R., 1984, Structural control of Coeur d’Alene ore deposits; pp. 49–51 in S. W. Hobbs (ed.), The Belt: Abstracts with Summaries — Belt Symposium II, 1983: Montana Bureau of Mines and Geology, Special Publication 90, 117 p.

    Google Scholar 

  • Reynolds, M. W., 1979, Character and extent of Basin-Range faulting, western Montana and east-central Idaho; pp. 185–193 in Proceedings of the Basin and Range Symposium: Rocky Mountain Association of Geologists/ Utah Geological Association, Salt Lake City, Utah, USA.

    Google Scholar 

  • ___, 1984, Tectonic setting and development of the Belt basin, northwestern United States; pp. 44–46 in S. W. Hobbs (ed.), The Belt: Abstracts with Summaries — Belt Symposium II, 1983: Montana Bureau of Mines and Geology, Special Publication 90, 117 p.

    Google Scholar 

  • Roby, R. N., 1950, Mines and Mineral Deposits (Except Fuels), Meagher County, Montana: U.S. Bureau of Mines, Information Circular 7540, 40 p.

    Google Scholar 

  • Rye, R O., J. F. Whelan, J. E. Harrison, and T. S. Hayes, 1984, The origin of copper-silver mineralization in the Ravalli Group as indicated by preliminary stable isotope studies; pp. 104–107 in S. W. Hobbs (ed.), The Belt: Abstracts with Summaries — Belt Symposium II, 1983: Montana Bureau of Mines and Geology, Special Publication 90, 117 p.

    Google Scholar 

  • Sawkins, F. J., 1984, Ore genesis by episodic dewatering of sedimentary basins: Application to giant Proterozoic lead-zinc deposits: Geology, v. 12, p. 451–454.

    Article  Google Scholar 

  • Shaffer, W.L., 1971, Geology of the Hogback Mountain Area, Northern Big Belt Mountains, Montana: MS thesis, University of New Mexico, Albuquerque, New Mexico, USA, 66 p.

    Google Scholar 

  • Thorson, J. P., 1984, Suggested revisions of the lower Belt Supergroup stratigraphy of the Highland Mountains, southwestern Montana; p. 10–12 in S. W. Hobbs (ed.), The Belt: Abstracts with Summaries — Belt Symposium II, 1983: Montana Bureau of Mines and Geology, Special Publication 90, 117 p.

    Google Scholar 

  • Wallace, C. A., J. E. Harrison, M. R. Klepper, and J. D. Wells, 1976, Carbonate sedimentary breccias in the Wallace Formation (Belt Supergroup), Idaho and Montana, and their paleogeographic significance [abstract]: Geological Society of America, Abstracts with Programs, v. 8, p. 1159.

    Google Scholar 

  • Weidman, R. M., 1965, The Montana lineament; pp. 137–143 in 16th Field Conference Guidebook: Billings Geological Society, Billings, Montana, USA, 169 p.

    Google Scholar 

  • Winston, D., 1983, Middle Proterozoic Belt Basin syndepositional faults and their influence on Phanerozoic thrusting and extension: American Association of Petroleum Geologists Bulletin, v. 67, p. 1361

    Google Scholar 

  • ___, 1986, Middle Proterozoic tectonics of the Belt basin, western Montana and northern Idaho; pp. 245–257 in S. M. Roberts (ed.), Belt Supergroup: A Guide to Proterozoic Rocks of Western Montana and Adjacent Areas: Montana Bureau of Mines and Geology, Special Publication 94, 311 p.

    Google Scholar 

  • Woodward, L. A, 1970, Time of emplacement of the Pinto Diorite, Little Belt Mountains, Montana: Wyoming Geological Association, Earth Science Bulletin, v. 3, no. 3, p. 15–26.

    Google Scholar 

  • ___, 1981, Tectonic framework of disturbed belt of west-central Montana: American Association of Petroleum Geologists Bulletin, v. 65, p. 291–302.

    Google Scholar 

  • Zartman, R. E., and J. S. Stacey, 1971, Lead isotopes and mineralization ages in Belt Supergroup rocks, northwestern Montana and northern Idaho: Economic Geology, v. 66, p. 849–860.

    Article  Google Scholar 

  • Zieg, G. A., 1981, Stratigraphy, Sedimentology, and Diagenesis of the Precambrian Upper Newland Limestone, Central Montana: MS thesis, University of Montana, Missoula, Montana, USA, 182 p.

    Google Scholar 

  • ___, and D. W. Godlewski, 1986, Road log no. 1: A traverse across the eastern Belt Basin from Neihart to Townsend, Montana; pp. 1–16 in S. M. Roberts (ed.), Belt Supergroup: A Guide to Proterozoic Rocks of Western Montana and Adjacent Areas: Montana Bureau of Mines and Geology, Special Publication 94, 311 p.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Geology, University of New Mexico, Albuquerque, New Mexico, 87131, USA

    Lee A. Woodward

Authors
  1. Lee A. Woodward
    View author publications

    You can also search for this author in PubMed Google Scholar

Editor information

Editors and Affiliations

  1. Earth Sciences and Resources Institute, University of South Carolina, Columbia, SC, USA

    Mervin J. Bartholomew

  2. Department of Geology, University of Montana, Missoula, MT, USA

    Donald W. Hyndman

  3. Department of Earth Sciences, Montana State University, Bozeman, MT, USA

    David W. Mogk

  4. Department of Geological Sciences, Queen’s University, Kingston, Ontario, Canada

    Robert Mason

Rights and permissions

Reprints and permissions

Copyright information

© 1992 Springer Science+Business Media Dordrecht

About this chapter

Cite this chapter

Woodward, L.A. (1992). Tectonic setting of Au-Ag deposits hosted by Proterozoic strata along the Lewis and Clark line, west-central Montana. In: Bartholomew, M.J., Hyndman, D.W., Mogk, D.W., Mason, R. (eds) Basement Tectonics 8. Proceedings of the International Conferences on Basement Tectonics, vol 2. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-1614-5_46

Download citation

  • DOI: https://doi.org/10.1007/978-94-011-1614-5_46

  • Publisher Name: Springer, Dordrecht

  • Print ISBN: 978-94-010-4703-6

  • Online ISBN: 978-94-011-1614-5

  • eBook Packages: Springer Book Archive

Publish with us

Policies and ethics

Search

Navigation