Mineralium Deposita

, Volume 29, Issue 3, pp 288–300 | Cite as

Microthermometry and geochemistry of fluid inclusions from the Tennant Creek gold-copper deposits: implications for ore deposition and exploration

  • Khin Zaw
  • D. L. Huston
  • R. R. Large
  • T. Mernagh
  • C. F. Hoffmann
Article

Abstract

Gold-copper-bismuth mineralization in the Tennant Creek goldfield of the Northern Territory occurs in pipe-like, ellipsoidal, or lensoidal lodes of magnetite ± hematite ironstones which are hosted in turbiditic sedimentary rocks of Proterozoic age. Fluid inclusion studies have revealed four major inclusion types in quartz associated with mineralized and barren ironstones at Ten nant Creek; (1) liquid-vapour inclusions with low liquid/vapour ratios (Type I), (2) liquid-vapour inclusions with high liquid/vapour ratios or high vapour/liquid ratios and characteristic dark bubbles (Type II), (3) liquid-vapour-halite inclusions (Type III), and (4) liquid-vapour inclusions with variable liquid/vapour ratios (Type V). Type I inclusions are present in the barren ironstones and the unmineralized portions of fertile ironstones, whereas Types II and III inclusions are recognized in fertile ironstones. Trails of Types II and III inclusions cut trails of Type I inclusions. Type I fluid inclusions have homogenization temperatures of 100° to 350 °C with a mode at 200° to 250 °C. Type II inclusions in mineralized ironstones (e.g. Juno, White Devil, Eldorado, TC8 and Gecko K-44 deposits) have homogenization temperatures of 250 °C to 600 °C with a mode of 350 °C. Type I fluid inclusions have a salinity range of 10 to 30 NaCl equiv. wt %. Salinity measurements on fluid inclusions in the mineralized zones gave a range of 10 to 50 NaCl equiv. wt % with a mode of 35 NaCl equiv. wt %. Fluid inclusion studies indicate that the Tennant Creek ironstones were formed from a relatively low temperature and moderately saline fluid, where as gold and copper mineralization was deposited from later hydrothermal fluids of higher temperature and salin ity. Gas analysis indicates the presence of N2 and CO2, with very minor CH4 in Types II inclusions but no N2 or CH4 gases in Type I inclusions. Microprobe analysis of the fluid inclusion decrepitates indicates that the inclusions from Tennant Creek contain sodium and calcium as dominant cations and potassium in a subordinate amount. The high temperatures (≥ 350 °C), high salinities (≥ 35 NaCl equiv. wt. %) and cation composition of the Tennant Creek ore fluids suggest that the ore fluids were derived from upward migrating heated basinal brines, although contribution from a magmatic source cannot be ruled out. Close association of vapour-rich Type IIb and salt-rich Type III inclusions in the mineralized ironstones (e.g. Juno, White Devil, Eldorado, TC8 and Gecko K-44) indicates heterogeneous trapping of ore fluids. This heterogeneous trapping is interpreted to be due to unmixing (exsolution) of a gas-rich (e.g. N2) fluid during the upward migration of the metal bearing brines and/or due to degassing caused by reaction of oxidized ore fluids and host ironstones. Fluid inclusion data have important implications regarding the deposition of gold in the ironstones, and may have application in discriminating fertile from barren ironstones.

Keywords

Fluid Inclusion Homogenization Temperature Fluid Inclusion Study Fluid Inclusion Data Basinal Brine 
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.

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References

  1. Black, L.P. (1984) U-Pb zircon ages and a revised chronology for the Tennant Creek Inlier, Northern Territory. Aust. J. Earth Sci. 31:123–131Google Scholar
  2. Bodnar, R.J., Reynolds, T.J., Kuehn, C.A. (1985a) Fluid inclusions systematics in epithermal systems. In: Berger, B.R., Bethke, P.M. (eds.) Geology and geochemistry of epithermal systems. Rev. Econ. Geol. 2:73–97Google Scholar
  3. Bodnar, R.J., Burnham, C.W., Sterner, S.M. (1985b) Synthetic fluid inclusions in natural quartz. III. Determination of phase equilibrium properties in the system H2O-NaCl to 1000°C and 1500 bars. Geochim. Cosmochim. Acta. 49:1861–1873Google Scholar
  4. Bottrell, S.H., Miller, M.F. (1990) The geochemical behaviour of nitrogen compounds during the formation of black shale hosted quartz vein gold deposits, north Wales. Appl. Geochem. 5:289–296Google Scholar
  5. Bottrell, S.H., Shepherd, T.J., Yardley, B.W.D., Dubessy, J. (1988) A fluid inclusion model for the genesis of the ores of the Dolgellau gold belt, north Wales. J. Geol. Soc. London 145:139–145Google Scholar
  6. Bowers, T.S. (1986) The geochemical consequences of H2-CO2 immiscibility on ore deposition: a reaction path approach. Geol. Soc. Am. Abstr. Prog. 18:545Google Scholar
  7. Burlinson, K. (1984) Exploration for gold at Pine Creek and Tennant Creek, N.T. and at Hall Creek, W.A. using the fluid inclusion decrepitation technique. Aus. I.M.M. Conf., Darwin, N.T., August 1984, pp. 373–375Google Scholar
  8. Burlinson, K. (1988) An instrument for fluid inclusion decrepitometry and example of its application. Bull. Mineral. 111:267–278Google Scholar
  9. Carpenter, A.B., Trout, M.L., Pickett, E.E. (1974) Preliminary report on the origin and chemical evolution of lead- and zinc-rich oil field brines in central Mississippi. Econ. Geol. 69:1191–1206Google Scholar
  10. Crawford, M.L. (1981) Fluid inclusions in metamorphic rocks — low and medium grade. In: Hollister, L.S., Crawford, M.L. (eds.) Fluid inclusions: applications to petrology. Mineral. Assoc. Can. 6: 157—181Google Scholar
  11. Crawford, M.L., Hollister, L.S. (1986) Metamorphic fluids: the evidence from fluid inclusions. In: Walther, J.V., Wood, B.J. (eds.) Fluid-rock interaction during metamorphism. Physical geochemistry, vol. 5. Springer, Berlin Heidelberg New York, pp. 1–35Google Scholar
  12. Eadington, P.J. (1974) Microprobe analysis of the non-volatile constituents of fluid inclusions. Neues Jahrb. Mineralogie Monatsh. 11:518–525PubMedGoogle Scholar
  13. Eastoe, C.J. (1978) A fluid inclusion study of the Panguna porphyry copper deposit, Bougainville, Papua New Guinea. Econ. Geol. 73:721–748Google Scholar
  14. Goldfarb, R.J., Leach, D.L., Rose, S.C., Landis, G.P. (1989) Fluid inclusion geochemistry of gold-bearing quartz veins of the Juneau gold belt, southern Alaska: implications for ore genesis. Econ. Geol. Monogr. 6:363–375Google Scholar
  15. Graney, J.R., Kesler, S.E., Jones, H.D. (1991) Application of gas analysis of jasperoid inclusion fluids to exploration for micron gold deposits. J. Geochem. Expl. 42:91–106Google Scholar
  16. Gulson, B.L., Large, R.R., Porritt, P.M. (1988) Gold exploration using lead isotopes at Tennant Creek, Australia. Appl. Geochem. 3:243–254Google Scholar
  17. Hanor, J.S. (1979) The sedimentary genesis of hydrothermal fluids. In: Barnes, H.L. (ed.) Geochemistry of hydrothermal ore deposits. Wiley, New York, pp. 137–172Google Scholar
  18. Haynes, F.M., Kesler, S.E. (1987a) Chemical evolution of brines during Mississippi Valley-type mineralization: evidence from East Tennessee and Pine Point. Econ. Geol. 82:53–71Google Scholar
  19. Haynes, F.M., Kesler, S.E. (1987b) Fluid inclusion chemistry in the exploration for Mississippi Valley-type deposits. An example from East Tennessee, U.S.A. Appl. Geochem. 2: 321–327Google Scholar
  20. Haynes, P.S., Kesler, S.E. (1987) Analysis of fluid inclusion gases in jasperoid as an exploration method for micron gold deposits. In: Elliott, I.L., Smee, B.W. (eds.) GEOEXPO/86. Exploration in the North American Cordillera. The Association of Exploration Geochemists, Rexdale, Canada, pp. 142–149Google Scholar
  21. Heinrich, C.A., Cousens, D.R. (1989) Semi-quantitative electron microprobe analysis of fluid inclusion salts from the Mount Isa copper deposit (Queensland, Australia). Geochim. Cosmochim. Acta 53:21–28Google Scholar
  22. Henley, R.W., Hoffmann, C. (1987) Complex hydrocarbons in fluid inclusions in gold and tin deposits. BMR Research Newsletter 6:1–2Google Scholar
  23. Ho,S.E. (1987) Fluid inclusions: their potential as an exploration tool for Archean gold deposits. In: Ho, S.E., Groves, D.I. (eds.) Recent advances in understanding Precambrian gold deposits. Geol. Dept. Univ. West Australia. Publ. No. 50:41–58Google Scholar
  24. Hoffmann, C.F., Henley, R.W., Higgins, N.C., Solomon M., Summons, R.E. (1988) Biogenic hydrocarbon in fluid inclusions from the Aberfoyle tin-tungsten deposit. Chem. Geol. 70:287–299Google Scholar
  25. Horvath, H.S. (1988) The geology and genesis of the Eldorado Au-bearing lode, Tennant Creek, N.T., Australia. Unpublished B.Sc. (Hons) thesis, University of Tasmania, Hobart, Australia, 110 ppGoogle Scholar
  26. Huston, D.L., Bolger, C., Cozens, G. (1993) A comparison of the Gecko K-44 and White Devil deposits: implications for ore genesis in the Tennant Creek district, Northern Territory, Australia. Econ. Geol. 88:1198–1225Google Scholar
  27. Kerrich, R. (1977) Some effects of tectonic recrystallization on fluid inclusions in vein quartz. Contrib. Mineral. Petrol. 59:195–202Google Scholar
  28. K, S.E. (1991) Introduction. In: Kesler, S.E. (ed.) Fluid inclusion gas analyses in mineral exploration. J. Geochem. Expl. 42:1–4Google Scholar
  29. Khin Zaw, Huston, D.L., Mernagh, T., Hoffman, C. (1990) A fluid inclusion study of Tennant Creek ironstones: implications for ore genesis and exploration. In: Gondwana: terranes and resources. 10th Australian Geological Convention, Hobart, Geol. Soc. Aust. Abstr. 25:290Google Scholar
  30. Kreulen, R., Schuiling, R.D. (1982) N2-CH4-CO2 fluids during formation of the Dome de L'Agout, France. Geochim. Cosmochim. Acta 46:193–203Google Scholar
  31. Landis, G.P., Hofstra, A.H. (1991) Fluid inclusion gas chemistry as a potential minerals exploration tool: case studies from Creede, CO, Jerritt Canyon, NV, Coeur d'Alene district, ID and MT, southern Alaska mesothermal veins, and mid-continent MVT's. In: Kesler, S.E. (ed.) Fluid inclusion gas analyses in mineral exploration. J. Geochem. Expl. 42:25–59Google Scholar
  32. Large, R.R. (1974) Gold-bismuth-copper mineralization in the Tennant Creek district, Northern Territory, Australia. Unpublished Ph.D. thesis, University of New England, Armidale, Australia, 288 ppGoogle Scholar
  33. Large, R.R. (1975) Zonation of hydrothermal minerals at the Juno Mine, Tennant Creek goldfield, central Australia. Econ. Geol. 70:1387–1413Google Scholar
  34. Lattanzi, P. (1991) Application of fluid inclusions in the study and exploration of mineral deposits. Eur. J. Mineral. 3:689–701Google Scholar
  35. Le Messurier, P., Williams, B.T., Blake, D.H. (1990) Tennant Creek Inlier — regional geology and mineralization. In: Hughes, F.E. (ed.) Geology of mineral deposits of Australia and Papua New Guinea. Australas. Inst. Mining Metall. Monogr. 14:829–838Google Scholar
  36. McPhie, J. (1994) A syn-sedimentary rhyolitic sill with pepperite margins: the Tennant Creek porphyry. Aust. J. Earth Sci. (in press)Google Scholar
  37. Moore, W.J., Nash, J.T. (1974) Alteration and fluid inclusion studies of the porphyry copper orebody at Bingham, Utah. Econ. Geol. 69:631–645Google Scholar
  38. Morrison, R.S., Donnellan, N., Hussey, K.J. (1992) Regional geology of Tennant Creek, N.T., Australia. GAC/MAC meeting, Wolfville, Nova Scotia, Canada, Abstracts 17:A80Google Scholar
  39. Nash, J.T. (1976) Fluid inclusion petrology — data from porphyry copper deposits and applications to exploration. U.S. Geol. Survey Prof. Paper 907D, 16 ppGoogle Scholar
  40. Nguyen, P.T. (1987) Structural geology and mineralization of the White Devil Mine, Tennant Creek, Northern Territory. Unpublished B.Sc. (Hons) thesis, University of Adelaide, Australia, 61 PPGoogle Scholar
  41. Nguyen, P.T., Booth, S.A., Both, R.A., James, P.R. (1989) The White Devil gold deposit, Tennant Creek, Northern Territory. Econ. Geol. Monogr. 6:180–192Google Scholar
  42. Norman, D.I., Sawkins, F.J. (1987) Analysis of volatiles in fluid inclusions by mass spectrometry. Chem. Geol. 61:1–10Google Scholar
  43. Noronha, F., Doria, A., Dubessy, J., Charoy, B. (1992) Characterization and timing of the different types of fluids present in the barren and ore-veins of the W-Sn deposit of Panasqueira, Central Portugal. Mineral. Deposita 27:72–79Google Scholar
  44. Pichavant, M., Ramboz, C., Weisbrod, A. (1982) Fluid immiscibility in natural processes: use and misuse of fluid inclusion data. I. Phase equilibria analysis — A theoretical and geometrical approach. Chem. Geol. 37:1–27Google Scholar
  45. Potter, R.W., II, Clynn, M.A., Brown, D.L. (1978) Freezing point depression of aqueous sodium chloride solutions. Econ. Geol. 73:284–285Google Scholar
  46. Ramboz, C., Pichavant, M., Weisbrod, A. (1982) Fluid immiscibility in natural processes: use and misuse of fluid inclusion data. II. Interpretation of fluid inclusion data in terms of immiscibility. Chem. Geol. 37:29–48Google Scholar
  47. Rattenbury, M.S. (1994) A link fold-thrust model for the deformation of the Tennant Creek goldfield. northern Australia. Mineral. Deposita 29:301–308Google Scholar
  48. Roedder, E. (1977) Fluid inclusions as tools in mineral exploration. Econ. Geol. 72:503–525Google Scholar
  49. Roedder, E. (1984) Fluid Inclusion. Mineral. Soc. Am. Rev. Mineralogy 12:644 ppGoogle Scholar
  50. Samson, I.M., Williams-Jones, A.E. (1991) C-O-H-N-salt fluids associated with contact metamorphism, McGerrigle Mountains, Quebec: a Raman spectroscopic study. Geochim. Cosmochim. Acta 55:169–177Google Scholar
  51. Skirrow, R.G., Walshe, J.L. (1993) The West Peko Au-Cu-Bi deposit, Tennant Creek, NT: fluid inclusion constraints on ore fluid chemistry. 2nd Meeting, Specialist Group in Economic Geology, Armidale, Geol. Soc. Australia Abstr. 34:72–73Google Scholar
  52. Shepherd, T.J., Miller, M.F. (1988) Fluid inclusion volatile as a guide to tungsten deposits, southwest England: application to other Sn-W provinces in western Europe. In: Boissonas, J., Omenetto, P. (eds.) Mineral deposits within the European Community. Springer, Berlin Heidelberg New York, pp. 29–52Google Scholar
  53. Stolz, A.J., Morrison, R. (1994) Proterozoic igneous activity in the Tennant Creek region, Northern Territory, Australia, and its relationships to Cu-Au-Bi mineralization. Mineral Deposita 29:261–274Google Scholar
  54. Touret, J.L.R. (1987) Fluid inclusions and pressure-temperature estimates in deep-seated rocks. In: Helgeson, H.C. (ed.) Chemical transport in metasomatic processes. Reidel, Dordrecht, pp. 91–121Google Scholar
  55. Vry, J.K., Brown, P.E., Beauchaine, J. (1988) Analysis of individual fluid inclusions by micro-FTIR spectroscopy. In: Newbury, D.E. (ed.) Microbeam analysis-1988. San Francisco Press, San Francisco, pp. 201–202Google Scholar
  56. Walsh, J.F., Kesler, S.E., Duff, D., Cloke, P.L. (1988) Fluid inclusion geochemistry of high-grade, vein-hosted gold ore at the Pamour mine, Porcupine Camp, Ontario. Econ. Geol. 83:1347–1367Google Scholar
  57. Wedekind, M.R. (1990) Geology and geochemistry of the Warrego Au-Cu-Bi mine, Tennant Creek, Northern Territory, Australia. Unpublished Ph.D. thesis, University of Tasmania, Hobart, Australia, 377 ppGoogle Scholar
  58. Wedekind, M.R., Large, R.R., Khin Zaw, Horvath, H., Gulson, B. (1988) The composition and source of ore depositing fluids in the Tennant Creek goldfield. Bicentennial Gold 88, Melbourne. Geol. Soc. Aust. Abstr. 23:492–494Google Scholar
  59. Wedekind, M.R., Large, R.R., Williams, B.T. (1989) Controls on high grade gold mineralization at Tennant Creek, Northern Territory, Australia. Econ Geol. Monogr. 6:168–179Google Scholar
  60. Williams-Jones, A.E., Samson, I.M., Linnen, R. (1989) Fluid evolution and its role in the genesis of the granite-related Madeleine copper deposit, Gaspe, Quebec. Econ. Geol. 84:1515–1524Google Scholar
  61. Wilson, J.W.J., Kesler, S.E., Cloke, P.L., Kelly, W.C. (1980) Fluid inclusion geochemistry of the Granisle and Bell porphyry copper deposits, British Columbia. Econ. Geol. 75:45–61Google Scholar
  62. Wopenka, B., Pasteris, J.D., Freeman, J.J. (1990) Analysis of individual fluid inclusions by Fourier transform infrared and Raman microscopy. Geochim. Cosmochim. Acta 54:519–533Google Scholar

Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • Khin Zaw
    • 1
  • D. L. Huston
    • 1
  • R. R. Large
    • 1
  • T. Mernagh
    • 2
  • C. F. Hoffmann
    • 3
  1. 1.Centre for Ore Deposit and Exploration StudiesUniversity of TasmaniaHobartAustralia
  2. 2.Australian Geological Survey OrganizationCanberraAustralia
  3. 3.Aspect Computing Pty. Ltd.BraddonAustralia

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