Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-24T03:25:01.323Z Has data issue: false hasContentIssue false
  • English
  • Français

Deformation textures in pyrite from the Vangorda Pb-Zn-Ag deposit, Yukon, Canada

Published online by Cambridge University Press:  05 July 2018

D. Brown  and
K. R. McClay
D. Brown
Affiliation:
Department of Geology, Royal Holloway, University of London, Egham, Surrey TW20 0EX, U.K.
K. R. McClay
Affiliation:
Department of Geology, Royal Holloway, University of London, Egham, Surrey TW20 0EX, U.K.
Get access Rights & Permissions [Opens in a new window]

Abstract

The Vangorda Pb-Zn-Ag orebody is a 7.1 M tonne, polydeformed stratiform massive sulphide deposit in the Anvil mining district, Yukon, Canada. Five sulphide lithofacies have been identified within the desposit with a typical mineralogy of pyrite, sphalerite, galena, and barite. Pyrrhotite-sphaleritemagnetite assembalges are locally developed. Etched polished sections of massive pyrite ores display relict primary depositional pyrite textures such as colloform growth zoning and spheroidal/framboidal features. A wide variety of brittle deformation, ductile deformation, and annealing textures have been identified. Brittle deformation textures include thin zones of intense cataclasis, grain indentation and axial cracking, and grain boundary sliding features. Ductile deformation textures include strong preferred grain shape orientations, dislocation textures, grain boundary migration, dynamic recrystallisation and pressure solution textures. Post deformational annealing has produced grain growth with lobate grain boundaries, 120° triple junctions and idioblastic pyrite porphyroblasts. The distribution of deformation textures within the Vangorda orebody suggests strong strain partitioning along fold limbs and fault/shear zones, it is postulated that focussed fluid flow in these zones had significant effects on the deformation of these pyritic ores.

Keywords

pyritedeformationtexturesVangorda depositYukonCanada
Type
Research Article
Information
Mineralogical Magazine , Volume 57 , Issue 386 , March 1993 , pp. 55 - 66
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1993

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

Atkinson, B. K. (1975) Experimental deformation of polycrystalline pyrite: effects of temperature, confining pressure, strain rate and porosity. Econ. Geol., 70, 473–87.Google Scholar
Atkinson, B. K. (1984) Subcritical crack growth in geological materials. J. Geophysical Res., 89, 4077–114.Google Scholar
Bell, T. H. (1985) Deformation partitioning and por-phyroblast rotation in metamorphic rocks: a radical reinterpretation. J. Metamorphic Geol., 3, 109–18.Google Scholar
Blacic, J. D. (1972) Effect of water on the experimental deformation of olivine. Am. Geophysical Union Mono, 16, 109–15.Google Scholar
Brill, B. A. (1989) Deformation and recrystallisation microstructures in deformed ores from the CSA mine, Cobar, N.S.W., Australia. J. Struct. Geol., 11, 591–501.Google Scholar
Brown, D. and McClay, K. R. (1992) Structure of the Vangorda Pb-Zn-Ag deposit, Anvil Range, Yukon Territory. In Current Research, Part A. Geol. Sur. of Canada, Paper 92-1A, 121-8.Google Scholar
Carne, R. C. and Cathro, R. J. (1982) Sedimentary exhalative (SEDEX) zinc-lead-silver deposits, northern Canadian Cordillera. Canadian Institute Mining and Metallurgy Bull., 75, no. 840, 66-78.Google Scholar
Carter, N. L., Kronenberg, A. K., Ross, J. V., and Wiltschko, D. V. (1990) Control of fluids on deformation of rocks. In Deformation Mechanisms, Rheology and Tectonics (R. J. Knipe and E. H. Rutter, eds.). Geol. Soc. Special Pub., 54, 1-13.Google Scholar
Couderc, J.-J., Bras, J., Fagot, M., and Levade, C. (1980) Etude par microscopie electronique en transmission de l'etat de deformation de pyrite de differ-entes provences. Bull. Mineral., 103, 547–57.Google Scholar
Cox, S. F., Etheridge, M. A., and Hobbs, B. E. (1981) The experimental ductile deformation of polycrystalline and single crystal pyrite. Econ. Geol., 76, 2105–18.Google Scholar
Craig, J. R., Vokes, F. M., and Simpson, C. (1991) Rotational fabrics in pyrite from Duektown, Tennessee. Ibid., 86, 1737-46.Google Scholar
Graf, J. L. and Skinner, B. J. (1970) Strength and deformation of pyrite and pyrrhotite. Ibid., 65, 206-15.Google Scholar
Graf, J. L. and Skinner, B. J. Bras, J., Fagot, M., Levade, C., and Couderc, J.-J. (1981) Transmission electron microscope observation of plastic deformation in experimentally deformed pyrite. Ibid., 76, 738-44.Google Scholar
Handin, J., Hager, R. V., Jr., Friedman, M., and Feather, J. N. (1963) Experimental deformation of sedimentary rocks under confining pressure: pore pressure tests. A.A.P.G. Bull., 46, 717–55.Google Scholar
Hobbs, B. E. (1981) The influence of metamorphic environment upon the deformation of minerals. Tectonophysics, 78, 335–83.Google Scholar
Hobbs, B. E. (1984) Point defect chemistry of minerals under a hydrothermal environment. X Geophysical Res., 89, 4026–38.Google Scholar
Hubbert, M. K. and Rubey, W. W. (1959) Role of fluid pressure in mechanics of overthrust faulting. 1 Mechanics of fluid-filled porous solids and its application to overthrust faulting. Geol. Soc. Amer. Bull., 70, 115–66.Google Scholar
Jennings, D. S. and Jilson, G. A. (1986) Geology and sulphide deposits of the Anvil Range, Yukon. In Mineral Deposits of Northern Cordillera (J. A. Morin, ed.) Canadian Institute Mining and Metallurgy, Special Paper 37, 319-61.Google Scholar
Kirby, S. H. (1984) Introduction and digest to the special issue on chemical effects of water on the deformation and strengths of rocks. J. Geophysical Res., 89, 3991–5.Google Scholar
Kirby, S. H. and Kronenberg, A. K. (1987) Rheology of the lithosphere: Selected topics. Reviews in Geophysics, 25, 1219–44.Google Scholar
McClay, K. R. (1983) Deformation of stratiform lead-zinc deposits. In Sediment-hosted Stratiform Lead-Zinc Deposits. Short Course Notes. Mineral. Assoc. Can. 283-307.Google Scholar
McClay, K. R. (1991) Deformation of stratiform Zn-Pb(-barite) deposits in the northern Canadian Cordillera. Ore Geology Reviews, 6, 435–62.Google Scholar
McClay, K. R. and Ellis, P. G. (1983) Deformation and recrystallisation of pyrite. Mineral. Mag., 47, 527–38.Google Scholar
McClay, K. R. (1984) Deformation of pyrite. Econ. Geol., 79, 400–3.Google Scholar
Mookherjee, A. (1971) Deformation of pyrite. Ibid., 66, 200.Google Scholar
McClay, K. R. (1976) Ores and metamorphism: Temporal and genetic relationships. In Handbook of Stratabound and Strataform Ore Deposits (K. H. Wolf, ed.) Elsevier, Amsterdam. 4, 203-60.Google Scholar
Natale, P. (1971) Prima segnalazione di struttre de deformazione plastica della pirite. Rend. Soc. Italian Miner. Petrol., 27, 539–50.Google Scholar
Pigage, L. C. (1990) Field guide Anvil Pb-Zn-Ag district, Yukon Territory, Canada. In Mineral Deposits of the Northern Canadian Cordillera, Yukon-northeastern British Columbia (J. G. Abbott and R. J. W. Turner, eds.) Geol. Sur. Canada, Open File 2169, 283-308.Google Scholar
Pigage, L. C. and Anderson, R. G. (1985) The Anvil Plutonic Suite, Faro, Yukon Territory. Can. J. Earth Sci., 22, 1204–16.Google Scholar
Pigage, L. C. and Jilson, G. A. (1985) Major extensional faults, Anvil Pb-Zn district, Yukon. G.S.A., Abstracts with Programs—Cordilleran Section, 17, 400.Google Scholar
Ramdohr, P. (1969) The Ore Minerals and Their Intergrowths. Pergamon Press, Oxford. 1174 pp.Google Scholar
Smith, J. M. and Erdmer, P. (1990) The Anvil aureole, an atypical mid-Creataceous culmination in the northern Canadian Cordillera. Can. J. Earth Sci., 27, 344–56.Google Scholar
Tempelman-Kluit, D. J. (1970) The relationship between sulphide grain size and metamorphic grade of host rocks in some stratbound pyrite ores. Ibid., 7, 1339-45.Google Scholar
Tempelman-Kluit, D. J. (1972) Geology and origin of the Faro, Vangorda and Swim concordant zinc-lead deposits, central Yukon Territory. Geol. Sur. Canada, Bull. 208. 73 pp.Google Scholar
Vokes, F. M. (1969) A review of the metamorphism of sulphide deposits. Earth-Sci. Rev., 95, 403–6.Google Scholar
Vokes, F. M. (1971) Some aspects of the regional metamorphic mobilisation of preexisting sulphide deposits. Mineral. Deposita, 6, 122–9.Google Scholar