Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-25T08:09:20.510Z Has data issue: false hasContentIssue false

Structural setting and timing of hydrothermal veins and breccias on Hurd Peninsula, South Shetland Islands: a possible volcanic-related epithermal system in deformed turbidites

Published online by Cambridge University Press:  01 May 2009

Robert C. R. Willan
Affiliation:
British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK

Abstract

Quartz veins and vein-breccias in a greywacke-shale sequence of ?Carboniferous-Triassic age were previously regarded as mesothermal silicified fault breccias, and related to an adjacent Eocene granodiorite pluton. New mapping of vein assemblages and textures, and their structural and cross-cutting relationships, demonstrates that the steeply dipping, sheeted, epithermal-textured vein array was hydraulic in origin and possibly Cretaceous in age. The main vein and breccia swarm trends for 14 km NNE along-strike and 2 km across-strike, cutting large irregular areas of silicified and brecciated sandstone, and patchy areas of pyritic, propylitic and K-feldspar alteration. Angular vein fabrics and hydraulic disruption textures indicate wedging by hydrothermal solutions, hydraulic rupture, brecciation and fragment transport, followed by open-space precipitation, in veins generally < 15 cm thick and breccias up to a few metres thick. Hydrothermal quartz, chlorite, calcite and chalcedony predominate, with variable amounts of chalcopyrite, galena, sphalerite and pyrite. Epidote, arsenopyrite, K-feldspar and andradite garnet are conspicuous in places. Breccias were pre-and syn-mineralization, whereas mineral precipitation was pre-, syn- and post-breccia formation. Hydrothermal activity was simultaneous with extensional faulting, striking NNE, and accompanied by intrusion of dacitic dykes. There followed conjugate shearing on east- and ESE-striking faults, intrusion of high-level tonalite stocks, and several phases of basaltic andesite dyke intrusion. These hypabyssal rocks were probably coeval with the Antarctic Peninsula Volcanic Group dominating Livingston Island, dated between 130 and 75 Ma. Minor copper and iron sulphide-bearing veins occur in adjacent volcanic and hypabyssal intrusive rocks. The Hurd Peninsula veins may, therefore, form part of a volcanic-epithermal hydrothermal system (adularia-sericite-quartz type), of Cretaceous age, rather than a porphyry-related system of Eocene age.

Type
Articles
Copyright
Copyright © Cambridge University Press 1994

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Baker, E. M., Kirwin, D. J. & Taylor, R. G. 1986. Hydrothermal breccia pipes. Economic Geology Research Unit Contributions no. 12. Townsville: Department of Geology, James Cook University of North Queensland, 45 pp.Google Scholar
Barker, P. F. 1982. The Cenozoic subduction history of the Pacific margin of the Antarctic Peninsula: ridge cresttrench interactions. Journal of the Geological Society, London 139, 787801.Google Scholar
Barker, P. F., Dalziel, I. W. D. & Storey, B. C. 1991. Tectonic development of the Scotia arc region. In The Geology of Antarctica (ed. Tingey, R. J.), pp. 215–44. Oxford: Clarendon Press.Google Scholar
Beach, A. 1977. Vein arrays, hydraulic fractures and pressure-solution structures in a deformed flysch sequence, S.W. England. Tectonophysics 40, 201–25.Google Scholar
Beaudoin, G. & Sangster, D. F. 1992. A descriptive model for silver-lead-zinc veins in clastic metasedimentary terranes. Economic Geology 87, 1005–21.CrossRefGoogle Scholar
Berger, B. R. & Bonham, H. F. 1990. Epithermal gold-silver deposits in the western United States; time-space products of evolving plutonic, volcanic and tectonic environments. Journal of Geochemical Exploration 36, 103–42.CrossRefGoogle Scholar
Birkenmajer, K. 1983. Late Cenozoic phases of block-faulting on King George Island (South Shetland Islands, West Antarctica), Bulletin of the Polish Academy of Sciences, Earth Sciences 30, 2132.Google Scholar
British Antarctic Survey (BAS). 1979. Northern Graham Land and South Shetland Islands: British Antarctic Survey 500G series, Sheet 2, scale 1:500000.Google Scholar
British Antarctic Survey (BAS). 1985. Tectonic map of the Scotia Arc: British Antarctic Survey BAS (Misc) 3, scale 1:3000000.Google Scholar
Burnham, C. W. 1985. Energy release in subvolcanic environments: implications for breccia formation. Economic Geology 80, 1515–22.CrossRefGoogle Scholar
Caminos, R., Marchese, H. G., Massabie, A. C., Morelli, J. R., Rinaldi, C. A. & Spikermann, J. P. 1973. Geologia del sector noroccidental de la Peninsula Hurd, Isla Livingston, Shetland de Sur, Antârtida Argentina. Contribución del Instituto Antártico Argentino 162, 132.Google Scholar
Chapman, J. L. & Smellie, J. L. 1992. Cretaceous fossil wood and palynomorphs from Williams Point, Livingston Island, Antarctic Peninsula. Review of Palaeobotany and Palynology 74, 163–92.CrossRefGoogle Scholar
Cox, C., Ciocanelea, R. & Pride, D. 1980. Genesis of mineralization associated with Andean intrusions, northern Antarctic Peninsula region. Antarctic Journal of the United States 15(5), 22–3.Google Scholar
Dalziel, I. W. D. 1972. Large-scale folding in the Scotia arc. In Antarctic Geology and Geophysics (ed. Adie, R. J.), pp. 4755. Oslo: Universitetsforlaget.Google Scholar
Dalziel, I. W. D. 1982. The early (pre-Middle Jurassic) history of the Scotia arc region: a review and progress report. In Antarctic Geoscience (ed. Craddock, C.), pp. 111–26. Madison: The University of Wisconsin Press.Google Scholar
Del Valle, R., Morelli, J. & Rinaldi, C. 1974. Manifestacion cupro-plumbifera “Don Bernabe” Isla Livingston, Islas Shetland del Sur Antá;rtida Argentina. Contribución del Instituto Antártico Argentino 175, 35 pp.Google Scholar
Dowling, K. & Morrison, G. 1989. Application of quartz textures to the classification of gold deposits using North Queensland examples. In The geology of gold deposits: the perspective in 1988 (eds Keays, R. R., Ramsay, W. R. H. and Groves, D. I.), pp. 342–55. El Paso: The Economic Geology Publishing Company. [Economic Geology Monograph 6].Google Scholar
Fletcher, C. J. N., Hawkins, M. P. & Tejada, R. 1989. Structural control and genesis of polymetallic deposits in the Altiplano and Western Cordillera of southern Peru. Journal of South American Earth Sciences 2, 6171.CrossRefGoogle Scholar
Fournier, R. O. 1991. The transition from hydrostatic to greater than hydrostatic fluid pressure in presently active continental hydrothermal systems in crystalline rock. Geophysical Research Letters 18, 955–8.Google Scholar
Goldfarb, R. J., Snee, L. W., Miller, L. D. & Newberry, R. J. 1991. Rapid dewatering of the crust deduced from ages of mesothermal gold deposits. Nature 354, 296–8.Google Scholar
Gonzalez-Ferran, O. 1991. The Bransfield rift and its active volcanism. In Geological Evolution of Antarctica (eds A., M. R., Crame Thomson, J. A. and Thomson, J. W.), pp. 505–9. Cambridge: Cambridge University Press.Google Scholar
Grikurov, G. E., Krylov, A. Y., Polyakov, M. M. & Tsovbun, Y. N. 1970. Age of rocks in the northern part of the Antarctic Peninsula and on the South Shetland Islands (according to potassium-argon data). Soviet Antarctic Expedition Information Bulletin 8, 61–3.Google Scholar
Grunow, A. M., Kent, D. V. & Dalziel, I. W. D. 1991. New palaeomagnetic data from Thurston Island: Implications for the tectonics of West Antarctica and Weddell Sea opening. Journal of Geophysical Research 96, 17935–54.CrossRefGoogle Scholar
Guilbert, J. M. & Park, C. F. 1986. The Geology of Ore Deposits, 1st ed. New York: W. H. Freeman and Company, 985 pp.Google Scholar
Heald, P., Foley, N. K. & Hayba, D. O. 1987. Comparative anatomy of volcanic-hosted epithermal deposits: acid-sulfate and adularia-sericite types. Economic Geology 82, 126.CrossRefGoogle Scholar
Hobbs, G. J. 1968. The geology of the South Shetland Islands: IV. The geology of Livingston Island. British Antarctic Survey Scientific Reports no. 47, 30 pp.Google Scholar
Hodgson, C. J. 1989. Patterns of mineralization. In Mineralization and Shear Zones (ed. Bursnall, J. T.), pp. 5188. Montréal: Geological Association of Canada. Short Course Notes Volume 6.Google Scholar
Laznicka, P. 1988. Breccias and Coarse Fragmentites. Developments in Economic Geology. Oxford: Elsevier, 832 pp.Google Scholar
Lindgren, W. 1933. Mineral deposits. 4th ed. London: McGraw-Hill, 930 pp.Google Scholar
Loske, W. P., Miller, H. & Kramm, U. 1988. U-Pb systematics of detrital zircons from low-grade metamorphic sandstones of the Trinity Peninsula Group (Antarctica). Journal of South American Earth Sciences 1, 301–7.Google Scholar
Maslanyj, M. P., Garrett, S. W., Johnson, A. C., Renner, R. G. B. & Smith, A. B. 1991. Aeromagnetic anomaly map of West Antarctica (Weddell Sea sector). BAS GEOMAP Series Sheet 2 1:2500000 with supplementary text. Cambridge: British Antarctic Survey, 37 pp.Google Scholar
Nicholson, R. & Ejiofor, I. B. 1987. The three-dimensional morphology of arrays of echelon and sigmoidal, mineral-filled fractures: data from north Cornwall. Journal of the Geological Society, London 144, Journal of the Geological Society, London83.CrossRefGoogle Scholar
Ortoimagen De La Isla De Livingston. 1992. Universitat de Barcelona: Departament de Geologia Dinàmìca, Geofísíca i Palaeontología, y Institut Cartogràfic de Catalunya.Google Scholar
Pallàs, R., Mulñoz, J. A. & Sàbat, F. 1992. Estratigrafía de la Formación Miers Bluff, Isla Livingston, Islas Shetland del Sur. In Geología de la Antárcida Occidental (ed. López-Martínez, J.), pp. 105–15. Madrid, III congreso Geológico de España [Simposios Tomo 3].Google Scholar
Pankhurst, R. J. & Smellie, J. L. 1983. K-Ar geochronology of the South Shetland Islands, Lesser Antarctica: apparent lateral migration of Jurassic to Quaternary island arc volcanism. Earth and Planetary Science Letters 66, 214–22.CrossRefGoogle Scholar
Panteleyev, A. 1988. A Canadian Cordilleran model for epithermal gold-silver deposits. In Ore deposit models (eds Roberts, R. G. and Sheahan, P. A.), pp. 3143. Ontario: Geological Association of Canada.Google Scholar
Phillips, W. J. 1986. Hydraulic fracturing effects in the formation of mineral deposits. Transactions of the Institution of Mining and Metallurgy, Section B, Applied Earth Science 95, B17–B24.Google Scholar
Pollard, D. D. & Aydin, A. 1988. Progress in understanding jointing over the past century. Geological Society of America Bulletin 100, 11811204.2.3.CO;2>CrossRefGoogle Scholar
Pride, D. E., Cox, C. A., Moody, S. V., Conelea, R. R. & Rosen, M. A. 1990. Investigation of mineralization in the South Shetland Islands, Gerlache Strait, and Anvers Island, northern Antarctic Peninsula. In Mineral resources potential of Antarctica (eds Splettstoesser, J. F. and Dreschhoff, G. A. M.), pp. 6994. Washington: American Geophysical Union.Google Scholar
Pride, D., Moody, S. & Rosen, M. 1981. Metallic mineralization, South Shetland Islands, Gerlache Strait, and Palmer Station. Antarctic Journal of the United States 16, 1314.Google Scholar
Rawlings, D. J. 1993. Mafic peperite from the Gold Creek volcanics in the Middle Proterozoic McArthur Basin, Northern Territory. Australian Journal of Earth Sciences 40, 109–13.CrossRefGoogle Scholar
Santanach, P., Pallàs, R., Sàbat, F. & Muñoz, J. A. 1992. La fracturacion en la Isla Livingston, Islas Shetland del Sur. In Geología de la Antártida Occidental (ed. López-Martínez, J.), pp. 141–51. Madrid, III Congreso Geológico de España [Simposios Tomo 3].Google Scholar
Sibbett, B. S. 1988. Size, depth and related structures of intrusions under stratovolcanoes and associated geothermal systems. Earth Science Reviews 25, 291309.CrossRefGoogle Scholar
Sibson, R. H. 1986. Brecciation processes in fault zones: inferences from earthquake rupturing. Pure and Applied Geophysics 124, 159–75.CrossRefGoogle Scholar
Sibson, R. H. 1987. Earthquake rupture as a mineralizing agent in hydrothermal systems. Geology 15, 701–4.Google Scholar
Sibson, R. H. 1990. Faulting and fluid flow. In Fluids in tectonically active portions of the continental crust (ed. Nesbitt, B. E.), pp. 93132. Short Course Handbook Volume 18. Ottawa: Mineralogical Association of Canada.Google Scholar
Sillitoe, R. H. 1985. Ore-related breccias in volcanoplutonic arcs. Economic Geology 80, 14671514.CrossRefGoogle Scholar
Sleep, N. H. & Blanpied, M. L. 1992. Creep, compaction and the weak rheology of major faults. Nature 359, 687–92.Google Scholar
Smellie, J. L. 1983. Syn-plutonic origin and Tertiary age for the (?)Precambrian False Bay Schists of Livingston Island, South Shetland Islands. British Antarctic Survey Bulletin 52, 2132.Google Scholar
Smellie, J. L. 1990. Graham Land and South Shetland Islands. In Volcanoes of the Antarctic Plate and Southern Oceans (eds LeMasurier, W. E., and Thomson, J. W.), pp. 302–59. Antarctic Research Series Volume 48. Washington, D.C.: American Geophysical Union.CrossRefGoogle Scholar
Smellie, J. L. 1991. Stratigraphy, provenance and tectonic setting of (?)Late Palaeozoic-Triassic sedimentary sequences in northern Graham Land and South Scotia Ridge. In Geological Evolution of Antarctica (eds Thomson, M. R. A., Crame, J. A. and Thomson, J. W.), pp. 411–17. Cambridge: Cambridge University Press.Google Scholar
Smellie, J. L., Pankhurst, R. J., Thomson, M. R. A. & Davies, R. E. S. 1984. The geology of the South Shetland Islands: VI. Stratigraphy, Geochemistry and Evolution. British Antarctic Survey Scientific Reports 87, 85 pp.Google Scholar
Storey, B. C. & Garrett, S. W. 1985. Crustal growth of the Antarctic Peninsula by accretion, magmatism and extension. Geological Magazine 122, 514.CrossRefGoogle Scholar
Thomson, M. R. A., Crame, J. A. & Thomson, J. W. 1991. Geological Evolution of Antarctica. Cambridge: Cambridge University Press, 722 pp.Google Scholar
Tokarski, A. K. 1991. The Late Cretaceous-Cenozoic structural history of King George Island, South Shetland Islands, and its plate tectonic setting. In Geological Evolution of Antarctica (eds Thomson, M. R. A., Crame, J. A. and Thomson, J. W.), pp. 493–7. Cambridge: Cambridge University Press.Google Scholar
Tsang, C. F. 1991. Coupled hydromechanical-thermochemical processes in rock fractures. Reviews of Geophysics 29, 537–51.CrossRefGoogle Scholar
Yoshida, Y., Kaminuma, K. & Shiraishi, K. 1992. Recent Progress in Antarctic Earth Science. Tokyo: Terra Scientific Publishing Company, 796 pp.Google Scholar