Abstract
The Hillgrove gold–antimony deposit is hosted in late Palaeozoic, biotite-grade metasedimentary rocks and Permo-Carboniferous granitoid intrusions of the New England Orogen. Mineralisation occurred at a range of structural levels during rapid uplift in the orogen at 255–245 Ma. Hydrothermal fluids were controlled by extensional faults in a regional-scale sinistral strike-slip fault system. Principal faults in this system were developed in, and possibly evolved from, mylonite zones which were active during Late Permian tectonics. Earliest mineralisation formed scheelite-bearing quartz veins, and these were followed by auriferous arsenopyrite–pyrite–quartz–carbonate veins with minor base metal sulphides. This latter type was accompanied by sericitisation and carbonation of the host rock, with addition of sulphur, arsenic and gold, in zones up to 20 m from veins. Quartz–stibnite veins with electrum, gold, aurostibite, and arsenopyrite form a prominent and economically important hydrothermal type, with little wall-rock alteration but extensive hydrothermal breccia formation and local open-space filling textures. Below a mining depth of 300–500 m, this type passes over a short distance downwards into stibnite-poor gold-bearing veins. Late-stage carbonate–stibnite veins with gold and silver sulphosalts cut all earlier veins, and have open-space filling textures. Aspects of the Hillgrove deposit have similarities to many other orogenic gold deposits in the SW Pacific which have been formed at different structural levels. Hillgrove is distinctive in having evidence for mineralisation at this wide range of structural levels in the one deposit, formed progressively during syn-orogenic uplift.
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References
Aitchison JC, Flood PG, Stratford JMC, Davis AM (1999) Conceptual advances in understanding the New England Orogen: a decade of progress. In: Flood PG (ed) New England Orogen. Earth Sciences, University of New England, Armidale, pp 1–11
Ashley PM (1997) Silica-carbonate alteration zones and gold mineralisation in the Great Serpentinite Belt, New England Orogen, New South Wales. Geol Soc Aust Spec Publ 19:212–225
Ashley PM, Craw D (1995) Carrick Range Au and Sb mineralisation in Caples Terrane, Otago Schist, Central Otago, New Zealand. N Z J Geol Geophys 38:137–149
Ashley PM, Cook NDJ, Hill RL (1990) Occurrence and significance of aurostibite in Sb-Au ore from Hillgrove, New South Wales, Australia. N Jahrb Mineral Monat 1990 H12:537–551
Ashley PM, Cook NDJ, Hill RL, Kent AJR (1994) Shoshonitic lamprophyre dykes and their relation to mesothermal Au-Sb veins at Hillgrove, New South Wales, Australia. Lithos 32:249–272
Ashley PM, Barnes RG, Golding SD, Stephens CJ (1996) Metallogenesis related to Triassic magmatism in the New England Orogen. Geol Soc Aust Ext Abstr 43:34–42
Ashley PM, Creagh CJ, Ryan CG (2000) Invisible gold in ore and mineral concentrates from the Hillgrove gold-antimony deposits, NSW, Australia. Miner Deposita 35:285–301
Barnes RG, Brown RE, Brownlow JW, Gilligan LB, Krynen J, Willis IL (1988) A review of the mineral deposits of the New England Orogen in New South Wales. In: Kleeman JD (ed) New England Orogen: tectonics and metallogenesis. Department of Geology and Geophysics, University of New England, Armidale, pp 211–227
Barnes RG, Brown RE, Brownlow JW, Stroud WJ (1991) Late Permian volcanics in New England—the Wandsworth Volcanic Group. Q Notes Geol Surv NSW 84:1–36
Becker J, Craw D, Horton T, Chamberlain CP (2000) Gold mineralization near the Main Divide, upper Wilberforce valley, Southern Alps, New Zealand. N Z J Geol Geophys 43:199–215
Bierlein FP, Crowe DE (2000) Phanerozoic orogenic lode gold deposits. Rev Econ Geol 13:103–139
Bierlein FP, Maher S (2001) Orogenic disseminated gold in Phanerozoic fold belts—examples from Victoria, Australia and elsewhere. Ore Geol Rev 18:113–148
Bierlein FP, Arne DC, McKnight S, Lu J, Reeves S, Besanko J, Marek J, Cooke D (2000) Wall-rock petrology and geochemistry in alteration halos associated with mesothermal gold mineralization, central Victoria, Australia. Econ Geol 95:283–311
Bierlein FP, Arne DC, Foster DA, Reynolds PR (2001) A geochronological framework for slate belt-hosted gold mineralisation in central Victoria, Australia. Miner Deposita 36:741–767
Boyle GO (1990) Hillgrove antimony-gold deposits. In: Hughes FE (ed) Geology of the mineral deposits of Australia and Papua New Guinea. Australas Inst Min Metall Mon 14:1425–1427
Christie AB, Brathwaite RL (2003) Hydrothermal alteration in metasedimentary rock-hosted orogenic gold deposits, Reefton goldfield, South Island, New Zealand. Miner Deposita 38:87–107
Collins WJ, Offler R, Farrell TR, Landenberger B (1993) A revised Late Palaeozoic-Early Mesozoic tectonic history for the southern New England Fold Belt. In: Flood PG, Aitchison JC (eds) New England Orogen, eastern Australia. Department of Geology and Geophysics, University of New England, Armidale, pp 69–84
Comsti EC, Taylor GR (1984) Implications of fluid inclusion data on the origin of the Hillgrove gold-antimony deposits, N.S.W. Proc Australas Inst Min Metall 289:195–203
Craw D, Norris RJ (1991) Metamorphogenic Au-W veins and regional tectonics: mineralisation throughout the uplift history of the Haast Schist, New Zealand. N Z J Geol Geophys 34:373–383
Craw D, Rattenbury MS, Johnstone RD (1987) Structural geology and vein mineralisation in the Callery River headwaters, Southern Alps, New Zealand. N Z J Geol Geophys 30:273–286
Craw D, Windle SJ, Angus PV (1999) Gold mineralization without quartz veins in a ductile-brittle shear zone, Macraes Mine, Otago Schist, New Zealand. Miner Deposita 34:382–394
Cunneen R (1996) Recent developments in the geology of the Gympie goldfield. Geol Soc Aust Ext Abstr 43:162–166
Dong G, Morrison G, Jaireth S (1995) Quartz textures in epithermal veins, Queensland—classification, origin, and implication. Econ Geol 90:1841–1856
Dowling K, Morrison G (1989) Application of quartz textures to the classification of gold deposits using north Queensland examples. Econ Geol Mon 6:342–355
Faure K, Matsuhisa Y, Metsugi H, Mizota C, Hayashi S (2002) The Hishikari Au-Ag epithermal deposit, Japan: oxygen and hydrogen isotope evidence in determining the source of palaeohydrothermal fluids. Econ Geol 97:481–498
Foster DA, Gray DR, Kwak TAP, Bucher M (1998) Chronology and tectonic framework of turbidite hosted gold deposits in the western Lachlan Fold Belt, Victoria. Ore Geol Rev 13:229–250
Gao ZL, Kwak TAP (1997) The geochemistry of wall rock alteration in turbidite-hosted gold vein deposits, central Victoria, Australia. J Geochem Explor 59:259–274
Gilligan LB, Brownlow JW, Cameron RG, Henley HF (1992) Metallogenic study and mineral deposit data sheets Dorrigo-Coffs Harbour 1:250 000 metallogenic map. Geological Survey of New South Wales, Sydney
Goldfarb RJ, Phillips GN, Nokleberg WJ (1998) Tectonic setting of synorogenic gold deposits of the Pacific Rim. Ore Geol Rev 13:185–218
Goldfarb RJ, Groves DI, Gardoll S (2001) Orogenic gold and geologic time: a global synthesis. Ore Geol Rev 18:1–75
Groves DI, Goldfarb RJ, Gebre-Mariam M, Hagemann SG, Robert F (1998) Orogenic gold deposits: a proposed classification in the context of their crustal distribution and relationship to other gold deposit types. Ore Geol Rev 13:7–27
Henley HF (1991) Lamprophyres and gold in the New England Fold Belt. Q Notes Geol Surv NSW 83:7–24
Hodgson CJ (1993) Mesothermal lode-gold deposits. In: Kirkham RV, Sinclair WD, Thorpe RI, Duke LM (eds) Mineral deposit modeling. Geol Assoc Can Spec Pap 40:635–678
Jenkins RB, Landenberger B, Collins WJ (2002) Late Palaeozoic retreating and advancing subduction boundary in the New England Fold Belt, New South Wales. Aust J Earth Sci 49:467–489
Kent AJR (1994) Geochronology and geochemistry of Palaeozoic intrusive rocks in the Rockvale region, southern New England Orogen, New South Wales. Aust J Earth Sci 41:365–379
Kitch RB, Murphy RW (1990) Gympie gold field. In: Hughes FE (ed) Geology of the mineral deposits of Australia and Papua New Guinea. Australas Inst Min Metall Mon 14:1515–1518
Landenberger B, Farrell TR, Offler R, Collins WJ, Whitford DJ (1995) Tectonic implications of Rb-Sr biotite ages for the Hillgrove Plutonic Suite, New England Fold Belt, N.S.W., Australia. Precambrian Res 71:251–263
Lang JR, Baker T (2001) Intrusion-related gold systems: the present level of understanding. Miner Deposita 36:477–489
Lark CA (1997) The petrological and geochemical discrimination of gold-bearing quartz veins and their wall rocks, Monkland Mine, Gympie, Queensland. BSc Hons Thesis, University of New England, Armidale
Li X, Kwak TAP, Brown RW (1998) Wallrock alteration in the Bendigo gold ore field, Victoria, Australia: uses in exploration. Ore Geol Rev 13:381–406
McClay K (1987) The mapping of geological structures. Geological Society of London Handbook Series
Moody TC, Ashley PM, Flood PG (1993) The early Permian Halls Peak Volcanics and associated massive sulphide deposits: implications for the southern New England Orogen. In: Flood PG, Aitchison JC (eds) New England Orogen, eastern Australia. Department of Geology and Geophysics, University of New England, Armidale, pp 331–336
Mustard R (2001) Granite-hosted gold mineralization at Timbarra, northern New South Wales, Australia. Miner Deposita 36:542–562
Nesbitt BE (1991) Phanerozoic gold deposits in tectonically active continental margins. In: Foster RP (ed) Gold metallogeny and exploration. Blackie, Glasgow, pp 104–132
Nesbitt BE, Muehlenbachs K (1989) Geology, geochemistry and genesis of mesothermal lode gold deposits of the Canadian Cordillera: evidence for ore formation from evolved meteoric water. Econ Geol Mon 6:553–563
Roberts J, Engel BA (1987) Depositional and tectonic history of the southern New England Orogen. Aust J Earth Sci 34:1–20
Sharpe EN, MacGeehan PJ (1990) Bendigo goldfield. In: Hughes FE (ed) Geology of the mineral deposits of Australia and Papua New Guinea. Australas Inst Min Metall Mon 14:1287–1296
Shaw SE, Flood RH (1981) The New England Batholith, eastern Australia: geochemical variations in time and space. J Geophys Res 86:10530–10544
Shaw SE, Flood RH (1993) A compilation of Late Permian and Triassic biotite Rb-Sr data from the New England Batholith and areas to the southeast. In: Carr PF (ed) Centre for Isotope Studies Res Rep 1991–92. Centre for Isotope Studies, CSIRO Minerals Research Laboratories, North Ryde, pp 151–155
Sibson RH (1987) Earthquake rupturing as a mineralizing agent in hydrothermal systems. Geology 15:701–704
Simpson CRJ, Mauk JL, Arehart GB, Mathews SJ (1995) The formation of banded epithermal quartz veins at the Golden Cross Mine, Waihi, New Zealand. In: Mauk JL, StGeorge JD (eds) Proc 1995 Pacrim Congr, Auckland, New Zealand. Austral Inst Min Metall, pp 545–550
Solomon M, Groves DI (2000) The geology and origin of Australia’s mineral deposits. Centre for Ore Deposit Research and Centre for Global Metallogeny Publ 32
Stroud WJ, Barnes RG, Brown RE, Brownlow JW, Henley HF (1999) Some aspects of the metallogenesis of the southern New England Fold Belt. In: Flood PG (ed) New England Orogen. Earth Sciences, University of New England, Armidale, pp 365–371
Acknowledgements
We are grateful to New England Antimony Mines and Glen Boyle for logistical help and access, and financial assistance with analyses. Chris Creagh initiated the project, which was supported financially by a University of New England research grant. Contribution from University of Otago research funds is also acknowledged. John Bedford performed XRF analyses. Constructive comments from Frank Bierlein and Phil Seccombe improved the manuscript.
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Ashley, P.M., Craw, D. Structural controls on hydrothermal alteration and gold–antimony mineralisation in the Hillgrove area, NSW, Australia. Miner Deposita 39, 223–239 (2004). https://doi.org/10.1007/s00126-003-0400-1
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DOI: https://doi.org/10.1007/s00126-003-0400-1