1887
Volume 7 Number 1
  • E-ISSN: 1365-2117

Abstract

Abstract

Mineral provinces in southern and central Africa are strongly controlled by major structural trends, the alignment of sedimentary basins and metamorphically induced thermal regimes deep in the crust. Ore deposits are preferentially located on cooler margins of orogenic belts and are ultimately end‐products of fluid expulsion out of the deeper parts of orogenic axes. Metamorphic and structural vectors within orogenic belts adjacent to major cratons show a trend of high‐grade thermal overprinting in the cores of axes and lower metamorphic regimes acting on the distal margins of orogens (e.g. foreland basins). This apparent pattern is considered to have importance in the expulsion of at least three generations of mineralizing fluids beginning with exhalative migration during diagenesis and culminating much later in thrust‐controlled expulsion onto adjacent craton margins. Fluids within the hydrosphere that accumulate initially through topographic gradients in the sediments mixed with components of the mantle (CO). After storage within the crust, migration, enforced by metamorphic processes, transferred fluids out of, and away from, high thermal regimes in the axes of belts, leading to their present preservation around the margins of the major cratonic nuclei.

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References

  1. Altermaan, A. W. & Hälbich, I. W. (1990) Thrusting, folding, and stratigraphy of the Ghaap Group along the southwestern margin of the Kaapvaal Craton. South Afr. J. Geol., 93, 553–566.
    [Google Scholar]
  2. Anderson, L. S. & Unrug, R. (1984) Geodpnamic evolution of the Bangweulu block, northern Zambia. Precambrian Res., 25, 187–212.
    [Google Scholar]
  3. Behr, H. J., Ahrendt, H., Porada, H. & Weber, K. (1983a) The sole dolomite at the base of the Naukluft Nappe Complex. In: Evolution of the Damara Orogen of SouthWest Afica /Namibia (Ed. by R. MC. G.Miller ),
  4. Spec. Publ. geol. Soc. S. Afr. 11, 185–197.
    [Google Scholar]
  5. Behr, H. J. & Horn, E. E. (1982) Fluid inclusion systems in metapiaya deposits and their relationships to mineralization and tectonics. Chem. Geol., 37, 173–189.
    [Google Scholar]
  6. Behr, H. J., Horn, E. E. & Porada, H. (1983b) Fluid inclusions and genetic aspects of the Damara orogen. In: Intracontinental Fold Belts (Ed. by H.Martin and F. W.Eder ), pp. 945. Springer‐Verlag, Berlin .
    [Google Scholar]
  7. Bennett, D. G. & Barker, A. J. (1992) High salinity fluids: the result of retrograde metamorphism in thrust zones. Geochim. Cosmochim. Acta, 56, 81–95.
    [Google Scholar]
  8. Borg, G. & Maiden, K. J. (1987) Basalt alteration and its relation to Middle Proterozoic stratabound copper‐silver‐gold deposits along the margin of the Kalahari Craton in SWA/Namibia and Botswana. In: Geochemistry and Mineralization of Proterozoic Volcanic Suites (Ed. by T. C.Pharoah , R. D.Beckinsale and D. T.Richard ), Spec. Publ. geol. Soc. Lond., 347–354.
    [Google Scholar]
  9. Burnard, P. G., Sweeney, M. A., Vaughan, D. J., Spiro, E. & Thirlwall, M. F. (1993) Sulfur and lead isotope constraints on the genesis of a southern Zambian massive sulfide deposit. Econ. Geol., 88, 418–436.
    [Google Scholar]
  10. Burnard, P. G., Sweeney, M. A., Vaughan, D. J., Spiro, E. & Thirlwall, M. F. (1993) Sulfur and lead isotope constraints on the genesis of a southern Zambian massive sulfide deposit. Econ. Ceol., 88, 418–436.
    [Google Scholar]
  11. Chamberlain, C. P. & Rumble, D. (1988) Thermal anomalies in a regional metamorphic terrane: An isotopic study of the role of fluids. J. Petrol., 29, 1215–1232.
    [Google Scholar]
  12. Clifford, T. N. (1966) Tectono‐metallogenic units and metallogenic provinces of Africa. Earth planet. Sci. Lett., 1, 421–434.
    [Google Scholar]
  13. Clifford, P. M., Rice, M. C., Pryer, L. L. & Fueten, F. (1987) Mass transfer in unmetamorphosed carbonates during low‐grade metamorphism of arenites. In: Deformation of Sediments and Sedimentary Rocks (Ed. by M. E.Jones , and R. M. F.Preston),
  14. Spec. Publ. geol. Sol. Lond.. 29, 197–209.
    [Google Scholar]
  15. Corner, B. (1989) The Beattie anomaly and its significance for crustal evolution within the Gondwana framework. In: Abstracts S. Afr. Geophysical Assoc. 1st Technical Meeting, pp. 15–16.
  16. Corner, B. (1991) Crustal architecture of the Precambrian of the Kaapvaal Province from Geophysical data. In: Precambrian Sedimentary Basins of Southern Africa (Compiled by P. G.Eriksson ),
  17. Terra Abstracts Supp. 3, to Terra Nova. 3, 5–6.
    [Google Scholar]
  18. Cosi, M., De Honis, A., Gosso, G., Hunziker, J., Martinotti, G., Moraito, S., Robert, J. P. & Ruhlman, F. (1992) Late Proterozoic thrust tectonics, high‐pressure metamorphism and uranium mineralization in the Domes Area, Lufilian Arc, northwestern Zambia. Precambrian Res., 58, 215–240.
    [Google Scholar]
  19. Crawford, M. L. & Holllister, L. S. (1986) Metamorphic fluids: the evidence from fluid inclusions. In: Fluid‐Rock Interactions During Metamorphism (Ed. by J. V.Walther and B. J.Wood ), pp. 89–108. Springer‐Verlag, New York .
    [Google Scholar]
  20. Crawford, M. L., Kraus, D. W. & Hollister, L. S. (1979) Petrologic and fluid inclusion study of calc‐silicate rocks, Prince Rupert, British Columbia. Am. J. Sci., 279, 1135–1159.
    [Google Scholar]
  21. Daly, M. C. (1988) Crustal shear zones in central Africa: a kinemetic approach to Proterozoic tectonics. Episodes, 11, 5–11.
    [Google Scholar]
  22. Duane, M. J. & Brown, R. W. (1991) Tectonic brines and sedimentary basins: further applications of fission track analysis in understanding Karoo Basin evolution (South Africa). Basin Res., 3, 187–195.
    [Google Scholar]
  23. Duane, M. J. & De Wit, M. J. (1988) Pb‐Zn ore deposits of the northern Caledonides: products of continental‐scale fluid mixing and tectonic expulsion during continental collision. Geology, 16, 999–1002.
    [Google Scholar]
  24. Duane, M. J. & Kruger, F. J. (1991) Geochronological evidence for tectonically driven brine migration during the Early Proterozoic Kheis orogeny of Southern Africa. Geophys. Res. Lett., 18, 975–978.
    [Google Scholar]
  25. Duane, M. I., Kruger, F. J., Roberts, P. J. & Smith, C. B. (1991) Pb and Sr isotope and origin of Proterozoic base metal (fluorite) and gold deposits, Transvaal Sequence, South Africa. Econ. Geol., 86, 1491–1505.
    [Google Scholar]
  26. Duba, A., Heikamp, S., Meurer, W., Nover, G. & Will, G. (1994) Evidence from borehole samples for the role of accessory minerals in lower‐crustal conductivity. Nature, 367, 59–61.
    [Google Scholar]
  27. Etheridge, M. A., Wall, V. J. & Vernon, R. H. (1983) The role of fluid phase during regional deformation and metamorphism. J. metamorphic Geol., 1, 205–226.
    [Google Scholar]
  28. Etheridge, M. A., Wall, V. J. & Vernon, R. H. (1984) High fluid pressures during regional metamorphism and deformation: implications for mass transport and deformation mechanisms. J. geophys. Res., 89, 4344–4358.
    [Google Scholar]
  29. Ferry, J. M. (1980) A case study of the amount and distribution of heat and fluid during metamorphism. Contrib. Min. Pet., 71, 373–385.
    [Google Scholar]
  30. Ferry, J. M. (1983) Mineral reactions and element migration during metamorphism of calcareous sediments from the Vassalboro Formation, south‐central Maine. Am. Miner., 68, 334–354.
    [Google Scholar]
  31. Ferry, J. M. (1984) A biotite isograd in South‐Central Maine, USA: mineral reactions, fluid transfer and heat transfer. J. Petrol., 25, 871–893.
    [Google Scholar]
  32. Frimmel, H. E., Le Roux, A. P., Knight, J. & Minter, W. E. L. (1993) A case study of the postdepositional alteration of the Witwatersrand Basal Reef Gold placer. Econ. Geol., 88, 249–265.
    [Google Scholar]
  33. Garven, G. & Freeze, R. A. (1984) Theoretical analysis of the role of groundwater flow in the genesis of stratabound ore deposits. I. Mathematical and numerical model. Am. J. Sci., 284, 1085–1124.
    [Google Scholar]
  34. Graham, C. M., Greig, E. M., Shepherd, S. M. F. & Turi, B. (1983) Genesis and mobility of H2O‐CO2 fluid phase during regional greenschist and epidote amphibolite facies metamorphism: a petrological and stable isotope study in the Scottish Dalradian. J. geol. Soc. Lond., 140, 577–599.
    [Google Scholar]
  35. Hallbauer, D. K. & Barton, J. M. (1987) Fossil gold placers of the Witwatersrand: a review of their mineralogy, geochemistry and genesis. Gold Bull., 20, 68–79.
    [Google Scholar]
  36. Harley, M. & Charlesworth, E. G. (1993) Controls and structural development of epigenetic mesothermal gold mineralization in the Sabie‐Pilgrims Rest Goldfield, Eastern Transvaal, South Africa. EGRU Cir., 268.
    [Google Scholar]
  37. Hollister, L. S. & Burrus, R. C. (1976) Phase equilibria in fluid inclusions from the Khtada lake metamorphic complex. Geochim. Cosmochim. Acta, 40, 163–175.
    [Google Scholar]
  38. Hughes, M. J. (1987) The Tsumeb ore body, Namibia, and related dolostone‐hosted base metal ore deposits of central Afica . PhD thesis, University of Witwatersrand, Johannesburg .
  39. Jolly, W. T. (1974) Behaviour of Cu, Zn, and Ni during prehnite‐pumpellyite rank metamorphism of the Keweenawan basalts, Northern Michigan. Econ. Geol., 69, 1118–1125.
    [Google Scholar]
  40. Kamona, F., Freidrich, G. H. & Sweeney, M. A. (1990) The Kabwe Pb‐Zn deposit in central Zambia. African Geology Colloquim, 15th, Nancy, France, Orleans, Centre Internat. Formation Exchanges Geol., Occasional Publ., 1990/2, 325–327.
    [Google Scholar]
  41. Kasch, K. W. (1979) Metamorphic history of the southern Damara belt around Omitara, SWA/Namibia. 16th Ann. Rpt., Precambrian Research Unit University of Cape Town, 90–100.
    [Google Scholar]
  42. Kasch, K. W. (1983) Regional P‐T variations in the Damara orogen with particular reference to early high‐pressure metamorphism along the southern margin, In: Evolution of the Damara Orogen. South West Africa/Namibia (Ed. by R. MC. G.Miller ), Spec. Publ. geol. Soc. S. Afr. 11, 243–253.
  43. Klemd, R., Hallbauer, D. K. & Barton, J. M. (1986) Styles of hydrothermal alteration in granitoid rocks along the northwestern margin of the Witwatersrand Basin. Geol. Soc. S. Afr. Geocongress 1986 Extended Abstracts, 149–153.
  44. Kröner, A. (1977) The Precambrian geotectonic evolution of Africa: plate accretion versus plate destruction. Precambrian Res., 4, 163–213.
    [Google Scholar]
  45. Kröner, A. (1982) Rb‐Sr geochronology and tectonic evolution of the Pan‐African belt of Namibia, Southwestern Africa. Am. J. Sci., 282, 1471–1507.
    [Google Scholar]
  46. Lasaga, A. C. (1988) Fluid flow and chemical reaction kinetics in metamorphic systems. Chem. Geol., 70, 80.
    [Google Scholar]
  47. Maiden, K. J., Innes, A. H., King, M. J., Master, S. & Pettitt, I. (1984) Regional controls on the localisation of stratabound copper deposits: Proterozoic examples from Southern Africa and South Australia. Precambrian Res., 25, 99–118.
    [Google Scholar]
  48. Marquer, D. & Burkhard, M. (1992) Fluid circulation, progressive deformation and mass‐transfer processes in the upper crust: the example of basement‐cover relationships in the External Crystalline Massifs, Switzerland. J. struct. Geol., 14, 1047–1057.
    [Google Scholar]
  49. Master, S. (1991a) Stratigraphy, tectonic setting, and mineralization of the early Proterozoic Magondi Supergroup, Zimbabwe: a review. Economic Geology Research Group, University of the Witwatersrand, Information Circular. 238, 1–75.
    [Google Scholar]
  50. Master, S. (1991b) The origin and controls on the distribution of copper and precious metal mineralisation at the Mangula and Norah mines, Mhangura, Zimbabwe , PhD thesis, University of the Witwatersrand, Johannesburg .
  51. Mauk, J. L., Kelly, W. C., van der Pluijm, B. A. & Seasor, R. W. (1992) Relations between deformation and sediment‐hosted copper mineralization: evidence from the White Pine part of the mid‐continent rift system. Geology, 20, 427–430.
    [Google Scholar]
  52. McManus, K. M. & Hanor, J. S. (1993) Diagenetic evidence for massive evaporite dissolution, fluid flow, and mass transfer in the Louisiana Gulf Coast. Geology, 21, 727–730.
    [Google Scholar]
  53. Miller, R. MCG. (1983) The Pan‐African Damara Orogen of South West Africa/Namibia. In: Miller, R. MCG. , (Ed.), Evolution of the Damara Orogen of South West Africa /Namibia (Ed. by R. MCG.Miller ),
  54. Spec. Publ. geol. Soc. S. Afr.. 11, 431–515.
    [Google Scholar]
  55. Moore, J. M., Watkeys, M. K. & Reid, D. L. (1990) The regional setting of the Aggeneys/Gamsberg base metal deposits, Namaqualand, South Africa. In: Regional Metamorphism of Ore Deposits and Genetic Implications (Ed. by P. G.Spry and L. T.Bryndzia ), Proc. 28th Int. Geology Congress, pp. 77–95. VSP Utrecht, The Netherlands.
    [Google Scholar]
  56. Morrison, J. & Valley, J. W. (1988) Post‐granulite facies fluid infiltration in the Adirondack Mountains. Geology, 16, 513–516.
    [Google Scholar]
  57. Norton, D. & Taylor, H. P. (1979) Quantative simulation of the hydrothermal systems of crystallizing magmas on the basis of transport theory and isotope data. J. Petrol., 20, 421.
    [Google Scholar]
  58. Oliver, J. (1986) Fluids expelled tectonically from orogenic belts: their role in hydrocarbon migration and other geologic phenomena. Geology, 14, 99–102.
    [Google Scholar]
  59. Pan, H. & Symons, D. (1993) Paleomagnetism of the Mississippi Valley‐type Newfoundland Zinc deposit: evidence for Denonian mineralization and host rock remagnetization in the northern Appalachians. 3. geophys. Res., 98, 22415–22427.
    [Google Scholar]
  60. Phillips, N., Law, J. D. & Myers, R. E. (1990) The role of fluids in the evolution of the Witwatersrand Basin. S. Afr. J. Geol., 93, 54–69.
    [Google Scholar]
  61. Pohl, W. (1987) Metallogeny of the northeastern Kibaran belt, Central Africa. Geol. J., 22, 103–119.
    [Google Scholar]
  62. Raybould, J. G. (1978) Tectonic controls on Proterozoic stratiform copper mineralization. Trans. Inst. Mining Metall., B79–B86.
  63. Richards, J. P., Cumming, G. L., Krstic, D., Wagner, P. A. & Spooner, E. T. (1988) Pb isotope constraints on the age of sulfide ore deposition and U‐Pb age of late uraninite veining at the Musoshi stratiform copper deposit, central African Copperbelt, Zaire. Econ. Geol., 83, 724–741.
    [Google Scholar]
  64. Rumble, D. (1988) Fluid flow in regional metamorphism. EOS Trans., 69, 464.
    [Google Scholar]
  65. Rumble, D., Ferry, J. M., Hoering, T. C. & Boucot, A. J. (1982) Fluid flow during metamorphism at the Beaver Brook fossil locality. Am. J. Sci., 282, 866–919.
    [Google Scholar]
  66. Saggerson, E. P. & Turner, L. M. (1980) Distribution of regional metamorphism in Africa. Geol. Rdsch., 69, 745–756.
    [Google Scholar]
  67. Schmidt‐Mumm, A., Behr, H.‐J. & Horn, E. E. (1987) Fluid systems in metaplaya sequences in the Damara Orogen (Namibia): evidence for sulfur‐rich brines ‐ general evolution and first results. Chem. Geol., 61, 135–145.
    [Google Scholar]
  68. Stuwe, K., Sandiford, M. & Powell, R. (1993) Episodic metamorphism and deformation in low‐pressure, high‐temperature terranes. Geology, 21, 829–832.
    [Google Scholar]
  69. Suk, D., Van der Voo, R. & Peacor, D. R. (1991) SEM/STEM observations of magnetite in carbonates of eastern north America: evidence for chemical remagnetization during the Alleghenian Orogeny. Geophys. Res. Lett., 18, 939–942.
    [Google Scholar]
  70. Sverjensky, D. & Garven, G. (1992) Tracing great fluid migrations. Nature, 356, 481–482.
    [Google Scholar]
  71. Sweeney, M. A., Binda, P. & Vaughan, D. J. (1991) Genesis of the ores of the Copperbelt. Ore Geology Rev., 6.
    [Google Scholar]
  72. Thomas, R. J. (1990) The distribution and genesis of precious and base metal mineralization in the Natal Metamorphic Province. S. Afr. J. Geol., 93, 683–695.
    [Google Scholar]
  73. Thompson, A. B. (1987) Some aspects of fluid motion during metamorphism. J. geol. Soc. Lond., 144, 309–312.
    [Google Scholar]
  74. Toft, P. B., Scowen, P. A. H., Arkani‐Hamed, J. & Francis, D. (1994) Demagnetization by hydration in deep‐crustal rocks in the Grenville province of Quebec, Canada: implications for magnetic anomalies of continent collision zones. Geology, 21, 999–1002.
    [Google Scholar]
  75. Touret, J. L. R. (1977) The significance of fluid inclusions in metamorphic rocks. In: Thermodynamics in Geology (Ed. by C. D. G.Fraser ), pp. 203–227. D. Reidel, Dordrecht .
    [Google Scholar]
  76. Touret, J. L. R. (1992) CO2 transfer between the upper mantle and the atmosphere: temporary storage in the lower continental crust. Terra Nova, 4, 87–98.
    [Google Scholar]
  77. Treloar, P. J. & Kramers, J. D. (1989) Metamorphism and geochronology of granulites and migmatitic granulites from the Magondi Mobile Belt, Zimbabwe. Precamb. Res., 45, 277–289.
    [Google Scholar]
  78. Unrug, R. (1988) Mineralization controls and source of metals in the Lufilian Fold belt, Shaba (Zaire), Zambia, and Angola. Econ. Geol., 843, 1247–1258.
    [Google Scholar]
  79. Von Gehlen, K. (1983) Sulphur isotopes in metamorphosed Precambrian Fe‐Pb‐Zn‐Cu sulphides and barpte at Aggeneys and Gamsberg, South Africa. Miner. Mag., 47, 481–486.
    [Google Scholar]
  80. Walther, J. V. & Orville, P. M. (1982) Rates of metamorphism and volatile production and transport in regional metamorphism. Contrib. Min. Pet., 79, 252–255.
    [Google Scholar]
  81. Walther, J. V. & Wood, B. J. (1986) Fluid‐Rock Interactions during Metamorphism. Advances in Physical Geochemistry , Vol. 5. Springer‐Verlap, New York .
    [Google Scholar]
  82. Wynne‐Edwards, H. R. (1976) Proterozoic ensialic orogenesis: the Millipede model of ductile plate tectonics. Am. J. Sci., 276, 927–953.
    [Google Scholar]
  83. Yardley, B. W. D., Bottrell, S. R. & Cliff, R. A. (1991) Evidence for a regional‐scale fluid loss event during mid‐crustal metamorphism. Nature, 349, 151–154.
    [Google Scholar]
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