Mineralium Deposita

, Volume 45, Issue 4, pp 393–410 | Cite as

Pb isotopic constraints on the formation of the Dikulushi Cu–Pb–Zn–Ag mineralisation, Kundelungu Plateau (Democratic Republic of Congo)

  • Maarten Haest
  • Jens Schneider
  • Christophe Cloquet
  • Kris Latruwe
  • Frank Vanhaecke
  • Philippe Muchez
Article

Abstract

Base metal–Ag mineralisation at Dikulushi and in other deposits on the Kundelungu Plateau (Democratic Republic of Congo) developed during two episodes. Subeconomic Cu–Pb–Zn–Fe polysulphide ores were generated during the Lufilian Orogeny (c. 520 Ma ago) in a set of E–W- and NE–SW-oriented faults. Their lead has a relatively unradiogenic and internally inhomogeneous isotopic composition (206Pb/204Pb = 18.07–18.49), most likely generated by mixing of Pb from isotopically heterogeneous clastic sources. These sulphides were remobilised and enriched after the Lufilian Orogeny, along reactivated and newly formed NE–SW-oriented faults into a chalcocite-dominated Cu–Ag mineralisation of high economic interest. The chalcocite samples contain only trace amounts of lead and show mostly radiogenic Pb isotope signatures that fall along a linear trend in the 207Pb/204Pb vs. 206Pb/204Pb diagram (206Pb/204Pb = 18.66–23.65; 207Pb/204Pb = 15.72–16.02). These anomalous characteristics reflect a two-stage evolution involving admixture of both radiogenic lead and uranium during a young fluid event possibly c. 100 Ma ago. The Pb isotope systematics of local host rocks to mineralisation also indicate some comparable young disturbance of their U–Th–Pb systems, related to the same event. They could have provided Pb with sufficiently radiogenic compositions that was added to less radiogenic Pb remobilised from precursor Cu–Pb–Zn–Fe polysulphides, whereas the U most likely originated from external sources. Local metal sources are also suggested by the 208Pb/204Pb–206Pb/204Pb systematics of combined ore and rock lead, which indicate a pronounced and diversified lithological control of the immediate host rocks on the chalcocite-dominated Cu–Ag ores. The Pb isotope systematics of polysulphide mineralisation on the Kundelungu Plateau clearly record a diachronous evolution.

Keywords

Dikulushi Cu–Ag deposit Lead isotopes Polysulphide vein-type mineralisation Lufilian Arc 

Notes

Acknowledgements

Our gratitude goes to the exploration department of Anvil Mining, which has provided logistic support during sample collection in the Dikulushi region in 2003, 2004 and 2006. We acknowledge W. Heijlen who collected the first set of samples in 2003 and we thank W. Heijlen and S. Dewaele for information on the Cu occurrences in the Kundelungu Plateau region. The constructive comments of Åke Johansson (NHM Stockholm, Sweden), an anonymous reviewer, associate editor Rolf Romer and editor Bernd Lehmann greatly improved this paper. JS thanks RLR for massive, robust and stimulating inputs. This research is financially supported by research grant G.0585.06 of the FWO-Vlaanderen.

References

  1. Armstrong RA, Master S, Robb LJ (2005) Geochronology of the Nchanga Granite, and constraints on the maximum age of the Katanga Supergroup, Zambian Copperbelt. J Afr Earth Sci 45:32–40CrossRefGoogle Scholar
  2. Batumike MJ, Kampunzu AB, Cailteux JLH (2006) Petrology and geochemistry of the Neoproterozoic Nguba and Kundelungu Groups, Katangan Supergroup, southeast Congo: implications for provenance, paleoweathering and geotectonic setting. J Afr Earth Sci 44:97–115CrossRefGoogle Scholar
  3. Batumike MJ, Cailteux JLH, Kampunzu AB (2007) Lithostratigraphy, basin development, base metal deposits, and regional correlations of the Neoproterozoic Nguba and Kundelungu rock successions, central African Copperbelt. Gondwana Res 11:432–447CrossRefGoogle Scholar
  4. Cabral AR, Beaudoin G (2007) Volcanic red-bed copper mineralisation related to submarine basalt alteration, Mont Alexandre, Quebec Appalachians, Canada. Miner Deposita 42:901–912CrossRefGoogle Scholar
  5. Cailteux JLH (1994) Lithostratigraphy of the Neoproterozoic Shaba-type (Zaïre) Roan supergroup and metallogenesis of associated stratiform mineralisation. J Afr Earth Sci 19:279–301CrossRefGoogle Scholar
  6. Dewaele S, Heijlen W, Muchez P (2004) Metallogenesis of polysulphide mineralisation in the Kundelungu plateau, Katanga, D.R.Congo. Katholieke Universiteit Leuven, Leuven, pp 1–36Google Scholar
  7. Dewaele S, Muchez Ph, Heijlen W, Boutwood A, Lemmon T, Tyler R (2006) Reconstruction of the hydrothermal history of the Cu-Ag vein-type mineralisation at Dikulushi, Kundelungu foreland, Katanga, D.R. Congo. J Geochem Explor 89:376–379CrossRefGoogle Scholar
  8. El Desouky H, Muchez P, Tyler R (2008a) The sandstone-hosted stratiform copper mineralisation at Mwitapile and its relation to the mineralisation at Lufukwe, Lufilian foreland, Democratic Republic of Congo. Ore Geol Rev 34:561–579CrossRefGoogle Scholar
  9. El Desouky HA, Muchez P, Dewaele S, Boutwood A, Tyler R (2008b) Post-orogenic origin of the stratiform Cu mineralisation at Lufukwe, Lufilian foreland, Democratic Republic of Congo. Econ Geol 103:555–582CrossRefGoogle Scholar
  10. Everett CE, Rye DM, Ellam RM (2003) Source or sink? An assessment of the role of the old red sandstone in the Genesis of the Irish Zn-Pb Deposits. Econ Geol 98:31–50CrossRefGoogle Scholar
  11. Faure G, Mensing TM (2005) Isotopes, principles and applications, 3rd edn. Wiley, New York, p 897Google Scholar
  12. François A (1974) Stratigraphie, tectonique et minéralisations dans l’arc cuprifère du Shaba (République du Zaïre). In: Bartholomé P (ed) Gisements Stratiformes et Provinces Cuprifères. La Société Géologique de Belgique, Liège, pp 79–101Google Scholar
  13. Galer SJG, Abouchami W (1998) Practical application of lead triple spiking for correction of instrumental mass discrimination. Abstr 8th Goldschmidt Conf, Mineral Mag 62A:491–492Google Scholar
  14. Haest M, Muchez P, Dewaele S, Franey N, Tyler R (2007) Structural control on the Dikulushi Cu-Ag deposit, Katanga, Democratic Republic of Congo. Econ Geol 102:1321–1333CrossRefGoogle Scholar
  15. Haest M, Muchez P, Dewaele S, Schneider J, Boyce AJ (2009) Petrographic, fluid inclusion and isotope study of the Dikulushi Cu-Ag deposit, Katanga (D.R.C.): implications for exploration. Miner Deposita 44:505–522CrossRefGoogle Scholar
  16. Haest M, Muchez P, Petit JCJ, Vanhaecke F (2010) The influence of supergene reworking on variations in the isotopic composition of Cu in the Dikulushi Cu-Ag deposit (Democratic Republic of Congo). Econ Geol 104:1055–1065CrossRefGoogle Scholar
  17. Hanson RE, Wardlaw MS, Wilson TJ, Mwale G (1993) U-Pb Zircon ages from the Hook granite massif and Mwembeshi dislocation - constraints on Pan-African deformation, plutonism, and transcurrent shearing in Central Zambia. Precambrian Res 63:189–209CrossRefGoogle Scholar
  18. Heier KS, Thoresen K (1971) Geochemistry of high grade metamorphic rocks, Lofoten-Vesterålen, North Norway. Geochim Cosmochim Acta 35:89–99CrossRefGoogle Scholar
  19. Hoffman KH, Condon DJ, Bowring SA, Crowley JL (2004) U-Pb zircon date from the Neoproterozoic Ghaub formation, Namibia: constraints on Marinoan glaciation. Geology 32:817–820CrossRefGoogle Scholar
  20. Kampunzu AB, Cailteux JLH, Moine B, Loris HNBT (2005) Geochemical characterisation, provenance, source and depositional environment of ‘Roches Argilo-Talqueses’ (RAT) and Mines Subgroups sedimentary rocks in the Neoproterozoic Katangan Belt (Congo): lithostratigraphic implications. J Afr Earth Sci 42:119–133CrossRefGoogle Scholar
  21. Levinson AA (1974) Introduction to exploration geochemistry. Applied Publishing Ltd., WilmetteGoogle Scholar
  22. Ludwig KR (1980) Calculation of uncertainties of U-Pb isotope data. Earth Planet Sci Lett 46:212–220CrossRefGoogle Scholar
  23. Manhes G, Allegre CJ, Dupre B, Hamelin B (1980) Lead isotope study of basic-ultrabasic layered complexes—speculations about the age of the earth and primitive mantle characteristics. Earth Planet Sci Lett 47:370–382CrossRefGoogle Scholar
  24. Master S, Rainaud C, Armstrong RA, Phillips D, Robb LJ (2005) Provenance ages of the Neoproterozoic Katanga Supergroup (Central African Copperbelt), with implications for basin evolution. J Afr Earth Sci 42:41–60CrossRefGoogle Scholar
  25. Porada H, Berhorst V (2000) Towards a new understanding of the Neoproterozoic-Early Palaezoic Lufilian and northern Zambezi Belts in Zambia and the Democratic Republic of Congo. J Afr Earth Sci 30:727–771CrossRefGoogle Scholar
  26. Rainaud C, Master S, Armstrong RA, Robb LJ (2005) Geochronology and nature of the Palaeoproterozoic basement in the Central African Copperbelt (Zambia and the Democratic Republic of Congo), with regional implications. J Afr Earth Sci 42:1–31CrossRefGoogle Scholar
  27. Richards JP, Cumming GL, Krstic D, Wagner PA, Spooner ETC (1988a) Pb isotope constraints on the age of sulphide ore deposition and U-Pb age of late uraninite veining at the Musoshi stratiform copper-deposit, central African copper belt, Zaire. Econ Geol 83:724–741CrossRefGoogle Scholar
  28. Richards JP, Krogh TE, Spooner ETC (1988b) Fluid inclusion characteristics and U-Pb rutile age of late hydrothermal alteration and veining at the Musoshi stratiform copper-deposit, central African copper belt, Zaire. Econ Geol 83:118–139CrossRefGoogle Scholar
  29. Romer RL (1996a) Vesuvianite new tool for the U-Pb dating of skarn ore deposits. Mineral Petrol 46:331–341CrossRefGoogle Scholar
  30. Romer RL (1996b) U-Pb systematics of stilbite-bearing low-temperature mineral assemblages from the Malmberget iron ore, northern Sweden. Geochim Cosmochim Acta 60:1951–1966CrossRefGoogle Scholar
  31. Romer RL, Boundy TM (1988) Interpretation of lead isotope data from the uraniferous Cu–Fe–sulfide mineralizations in the Proterozoic greenstone belt at Kopparåsen, northern Sweden. Miner Deposita 23:256–261CrossRefGoogle Scholar
  32. Romer RL, Wright JE (1993) Lead mobilization during tectonic reactivation of the western Baltic Shield. Geochim Cosmochim Acta 57:2555–2570CrossRefGoogle Scholar
  33. Sabine J, Turner W, Bradford P, Dawson T, Brown K (2008) Anvil mining annual report 2008. Anvil Mining, Perth, p 72Google Scholar
  34. Stacey JS, Kramers JD (1975) Approximation of terrestrial lead isotope evolution by a 2-stage model. Earth Planet Sci Lett 26:207–221CrossRefGoogle Scholar
  35. Thirlwall MF (2002) Multicollector ICP-MS analysis of Pb isotopes using a 207Pb-204Pb double spike demonstrates up to 400 ppm/amu systematic errors in Tl-normalization. Chem Geol 184:255–279CrossRefGoogle Scholar
  36. Torrealday H, Hitzman M, Stein H, Markley R, Armstrong R, Broughton D (2000) Re–Os and U–Pb dating of the vein-hosted mineralisation at the Kansanshi copper deposit, northern Zambia. Econ Geol 95:1165–1170CrossRefGoogle Scholar
  37. Trefois P, Fernandez M (2000) Updating the geological map of Katanga (D.R. of Congo) with space imagery combined to archive data compilations Fourteenth International Conference on Applied Geologic Remote Sensing. Veridian ERIM International, Las Vegas, Nevada, pp 369–376Google Scholar
  38. White WM, Albarède F, Télouk P (2000) High-precision analysis of Pb isotope ratios by multicollector ICP-MS. Chem Geol 167:257–270CrossRefGoogle Scholar
  39. Zartman RE, Doe BR (1981) Pumbotectonics-the model. Tectonophysics 75:135–162CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Maarten Haest
    • 1
    • 2
  • Jens Schneider
    • 1
    • 3
  • Christophe Cloquet
    • 4
  • Kris Latruwe
    • 5
  • Frank Vanhaecke
    • 5
  • Philippe Muchez
    • 1
  1. 1.Geodynamics and Geofluids Research GroupKULeuvenHeverleeBelgium
  2. 2.Centre for 3D Mineral Mapping, CSIROKensingtonAustralia
  3. 3.Department of MineralogyTechnische Universität Bergakademie FreibergFreibergGermany
  4. 4.Centre de Recherches Pétrographiques et GéochimiquesVandoeuvre lès NancyFrance
  5. 5.Department of Analytical ChemistryGhent UniversityGhentBelgium

Personalised recommendations