Time- and Strata-Bound Features of the Michigan Copper Deposits (USA)

  • G. C. Amstutz


The Lake Superior Copper deposits in the Keweenaw lavas may be explained by a uniform single origin. The congruence analysis in the field, in hand specimens and with the microscope, as well as paragenetic and chemical analyses led to the conclusion that the copper is a comagmatic (contemporaneous) constitutent accumulated in hydromagmatic (deuteric) phases of the Keweenaw basalt magmas. The copper was carried up, in and with the lavas and crystallized in and with the deuteric phases of these lavas. Some parts of these phases escaped into fractures and into overlaying later flows or sediments (mostly porous conglomerates). The hydromagmatic (deuteric) phases show a distinct crystallization sequence in which the native copper occupies a distinct place. The high degree of congruence existing between the compositional variations and the primary lava features (flow lines, layering, breccia generations, dyklets, etc) rules out a later overall redistribution of elements (or minerals) for most of the copper sections. Burial metamorphism may have changed some of the originally basaltic material, but did not upset the stability of the deuteric phases, which are also of a low temperature — low pressure origin.


Copper Deposit Hydrous Mineral Native Copper Hydrothermal Vein Normal Basalt 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Amstutz, G.C.: The genesis of the Lake Superior copper deposits. Inst. Lake Superior Copper Geol. Program, p. 25 (abstract) (1958a)Google Scholar
  2. Amstutz, G.C.: Spilitic rocks and mineral deposits. Bull. Missouri School of Mines., Tech. Ser. 96, 11 p. (1958b)Google Scholar
  3. Amstutz, G.C.: Syngenetic zoning in ore deposits. Proc. Geol. Assoc. Canada 11, 95–113 (Fig. 7 on zoning in Michigan lavas) (1959a)Google Scholar
  4. Amstutz, G.C.: Syngenese und Epigenese in Petrographie und Lagerstättenkunde. Schweiz. Mineral. Petrogr. Mitt. 39, 1–84 (1959b)Google Scholar
  5. Amstutz, G.C.: Spilites and spilitic rocks. In: The Poldervaart Treatise on Rocks of Basaltic Composition. Hess, H.H., Poldervaart, A. (eds.). New York: Wiley Interscience 1968, pp. 737–753Google Scholar
  6. Amstutz, G.C.: Space, time and symmetry in zoning. Symp. Problems of Postmagmatic Ore Deposition (Prague), Vol. I, 1963, pp. 33–37Google Scholar
  7. Amstutz, G.C.: Some comments on the genesis of ores. Symp. Problems of Postmagmatic Ore Deposition (Prague), Vol. II, 1965, 147–150.Google Scholar
  8. Amstutz, G.C.: Die Kupfererzlagerstätten in den Laven vom Oberen See: Deutung neuer Beobachtungen. Clausthal: GDMB, 1966a, pp. 67–74Google Scholar
  9. Amstutz, G.C.: La Symmétrie comme critère génétique en géochimie et en gitologie. Bull. Suisse Mineral. Petrol. 46, 329–335 (1966b)Google Scholar
  10. Amstutz, G.C. (ed.): Spilites and Spilitic Rocks. IUGS Ser. A, No. 4. Berlin-Heidelberg-New York: Springer 1974, 482 p.Google Scholar
  11. Amstutz, G.C.: The logic of relations in ore genesis. Proc. 15th Inter-University Geol. Congress, 1967, Leicester, England, pp. 13–26Google Scholar
  12. Broderick, T.M.: The origin of the Michigan copper deposits. Econ. Geol. 47, 215–220 (1952)CrossRefGoogle Scholar
  13. Broderick, T.M.: Copper deposits of the Lake Superior region. Econ. Geol. 51, 285–287 (1956)CrossRefGoogle Scholar
  14. Cornwall, H.R.: Differentiation in magmas of the Keweenawan Series. J. Geol. 59, 151–172 (1951a)CrossRefGoogle Scholar
  15. Cornwall, H.R.: Differentiation in lavas of the Keweenawan Series and the origin of the copper deposits of Michigan. Bull. Geol. Soc. Am. 62, 159–202 (1951b)CrossRefGoogle Scholar
  16. Cornwall, H.R.: A summary on ideas of the origin of native copper deposits. Econ. Geol. 51, 615–631 (1956)CrossRefGoogle Scholar
  17. Jenney, C.P.: The Coppermine River Area, Northwest Territories, Canada. Proc. Geol. Assoc. Can. 6, 11–26 (1954)Google Scholar
  18. Leith, C.K., Lund, R.J., Leith, A.: Pre-Cambrian rocks of the Lake Superior region. U.S. geol. Survey Prof. Paper 184, 34 p.Google Scholar
  19. Lindgren, W.: Mineral Deposits. 4th ed. New York: McGraw-Hill 1933, 930 p.Google Scholar
  20. Moffit, F.H., Capps, S.R.: Geology and mineral resources of the Nizira district, Alaska. USGS Bull. 448, I–III (Amygdaloidal copper, 79–83) (1911)Google Scholar
  21. Niggli, P.: The chemistry of the Keweenawan lavas. J. Sci., Bowen Vol. 381–412 (1952)Google Scholar
  22. Pumpelly, R.: Copper District. Geol. Survey of Michigan; Upper Peninsula (1869–1873), I, Part 2, New York.Google Scholar
  23. Pumpelly, R.: The paragenesis and derivation of copper and its associates on Lake Superior. Am. J. Sci., 3rd Ser. 2, 188–198, 243–258, 347–355 (1874)Google Scholar
  24. Rickard, T.A. (ed.): Ore deposits. Discussion in: Ore Deposits, A Discussion. Eng. Mining J., New York, May 1903, 1–17; 56–60 (1903)Google Scholar
  25. Smith, R.E.: The production of spilitic lithologies by bural metamorphism of flood basalts from the Canadian Keweenawan, Lake Superior. In: Spilites and Spilitic Rocks. Amstutz, G.C. (ed). Berlin-Heidelberg-New York: Springer 1974, pp. 403–416Google Scholar
  26. Walger, E.: Über die postmagmatischen Umwandlungserscheinungen an den Melaphyren des Pfälzer Berglandes. Unpubl. thesis, Freiburg (Germany), 98 p.Google Scholar
  27. White, W.S.: Regional Structural Setting of the Michigan Native Copper District. Michigan: College of Mining and Technology Press, Institute on Lake Superior Geology, 1956, pp. 3–16Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1977

Authors and Affiliations

  • G. C. Amstutz
    • 1
  1. 1.HeidelbergGermany

Personalised recommendations