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New discovery of epithermal gold at Chahnali prospect, Bazman volcano, SE-Iran

  • Farahnaz Daliran
  • Werner H. Paar
  • Franz Neubauer
  • Bahman Rashidi

Abstract

Recent exploration in the region of Bazman in SE-Iran led to the discovery of gold mineralization in different prospects. The epithermal gold mineralization at Chahnali prospect is hosted by late Tertiary andesites and dacites which had been affected by a widespread and intense alteration including propylitization, argillitization, and silicification. The propylitization was of regional scale and predated the mineralizing events.

A first-stage gold mineralization occurs along a series of N-S to N30E trending tensional structures, mainly quartz veins. Trace amounts of gold can be found in individual quartz veins and stockworks that exhibit colloform banding and cockade textures, typical of open-space filling. Native gold, both visible and refractory (< 10 <m) is present, and a considerable portion of it occurs in grains < 5 <m (first gold stage). Minor quantities of sulfides (mainly pyrite) are associated with this event too.

The main gold-forming event, a second-stage gold mineralization is associated with a late-stage brecciation and subsequent silicification, which most likely were produced as a result of sinistral faulting along NNE-trending zones. Visible and refractory gold formed together with base metals, which include galena, chalcopyrite, sphalerite, and pyrite. Locally, weathering has led to the formation of jarosite-type minerals, which may contain very fine-grained gold. The gold mineralization is closely associated with quartz-adularia alteration. Therefore it is of low-sulfidation type and was generated in an epithermal environment. The initial results of a first reconnaissance study in Chahnali prospect indicate a remarkable potential for gold in the Bazman region. Further studies are needed to confirm the economic significance with an estimated gold grades averaging at 3–4 ppm.

Keywords

Bazman Iran epithermal gold low-sulfidation exploration 

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References

  1. Alavi M (1994) Tectonics of the Zagros orogenic belt of Iran; new data and interpretations. Tectonophysics 229: 211–238CrossRefGoogle Scholar
  2. Daliran F (2003) Discovery of 1.2 kg/t gold and 1.9 kg/t silver in mud precipitates of a cold spring from the Takab geothermal field, NW Iran. In: Eliopoulos et al (eds) Mineral Exploration and Sustainable Development, Millpress, Rotterdam: 461–464Google Scholar
  3. Daliran F, Hofstra AH, Walther J, Stüben D (2002) Agdarreh and Zarshuran SRHDG deposits, Takab region, NW-Iran. Geological Society of America Annual Meeting 2002, Abstract 98: 63–8Google Scholar
  4. Henley RW (1991) Epithermal gold deposits in volcanic terranes. In: Foster RP (ed) Gold metallogeny and exploration. Blackie, Glasgow, 133–164Google Scholar
  5. Lescuyer JL, Hushmandzadeh A, Daliran F (2003) Gold metallogeny in Iran: a preliminary review. In: Eliopoulos et al (eds) Mineral Exploration and Sustainable Development. Millpress, Rotterdam, 1185–1188Google Scholar
  6. Pars Kani Co (2003) Preliminary report on the prospection of epithermal gold mineralization in Chahnali north of Bazman, Sistan-va-Baluchestan province, Southeast Iran. Internal Rpt 136(in Farsi language with English abstract)Google Scholar
  7. Walker R, Jackson J (2004) Active tectonics and late Cenozoic strain distribution in central and eastern Iran. Tectonics 23, TC5010, doi:10.1029/2003TC001529CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Farahnaz Daliran
    • 1
  • Werner H. Paar
    • 2
  • Franz Neubauer
    • 3
  • Bahman Rashidi
    • 4
  1. 1.Institute of Mineralogy and GeochemistryUniversity of KarlsruheKarlsruheGermany
  2. 2.Division of Mineralogy and Material ScienceUniversity of SalzburgSalzburgAustria
  3. 3.Division of Geology and GeodynamicsUniversity of SalzburgSalzburgAustria
  4. 4.TehranIran

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