Opis

• Tytuł:
  First report on the occurrence of CO2-bearing fluid inclusions in the Meiduk porphyry copper deposit, Iran: implications for mineralisation processes in a continental collision setting
• Twórca:
  Asadi, Sina;
  Moore, Farid;
  Zarasvandi, Alireza;
  Khosrojerdi, Majid
• Opis:
  Hydrothermal alteration of the Meiduk porphyry copper deposit, south of the Kerman Cenozoic magmatic arc and southeast of the central Iranian volcano-plutonic belt has resulted in three stages of mineralisation characterised by veins and veinlets. These are, from early to late: (1) quartz + K-feldspar + biotite + pyrite ± chalcopyrite ± pyrrhotite ± magnetite (early potassic alteration and type-A veins); (2) quartz + chalcopyrite + pyrite + bornite + pyrrhotite + K-feldspar + biotite + magnetite (potassic-sericitic alteration and type-B veins); and (3) quartz + pyrite + chalcopyrite + sericite (sericitic alteration and type-C veins). Most ores were formed during stages 2 and 3. Three main types of fluid inclusions are distinguished based on petrographical, microthermometrical and laser Raman spectroscopy analyses, i.e. type I (three-phase aqueous inclusions), type II (three-phase liquid-carbonic inclusions) and type III (multi-phase solid inclusions). The fluid inclusions in quartz veins of the stages are mainly homogenised at 340–530°C (stage 1), 270–385°C (stage 2) and 214–350°C (stage 3), respectively, with salinities of 3.1–16 wt.% NaCl equivalent, 2.2–43 wt.% NaCl equivalent and 8.2–22.8 wt.% NaCl equivalent, respectively. The estimated trapping pressures are 97.9-123.6 MPa (3.7-4.6 km) in stage 1 and 62.5-86.1 MPa (2.3-3.1 km) in stage 2, respectively. These fluid inclusions are homogenised in different ways at similar temperatures, suggesting that fluid boiling took place in stages 2 and 3. The fluid system evolved from high-temperature, medium-salinity, high-pressure and CO2-rich to low-temperature, low-pressure, high-salinity and CO2-poor, with fluid boiling being the dominating mechanism, followed by input of meteoric water. CO2 escape may have been a factor in increasing activities of NaCl and S2- in the fluids, diminishing the oxidation of the fluids from stage 1 to 3. The result was precipitation of sulphides and trapping of multi-phase solid inclusions in hydrothermal quartz veins.
• Dostępność obiektu:
  Dostęp otwarty
• Prawa:
  Prawa autorskie (c) 2014 Sina Asadi, Farid Moore, Alireza Zarasvandi, Majid Khosrojerdi;
  https://creativecommons.org/licenses/by-nc-nd/3.0/
• Data:
  2014.01.29
• Typ:
  info:eu-repo/semantics/article;
  info:eu-repo/semantics/publishedVersion;
  Research papers
• Język:
  angielski
• Źródło:
  Geologos; Vol. 19 No. 4 (2013); 301-320;
  Geologos; Tom 19 Nr 4 (2013); 301-320;
  2080-6574;
  1426-8981
• Format:
  application/pdf
• Wydawca:
  Adam Mickiewicz University Poznan
• Relacja: http://pressto.amu.edu.pl/index.php/logos/article/view/logos-2013-0019/30389
• Temat i słowa kluczowe:
  CO2-bearing fluid inclusions;
  laser Raman spectroscopy;
  collision;
  Meiduk porphyry copper deposit;
  Iran
• Identyfikator: http://pressto.amu.edu.pl/index.php/logos/article/view/logos-2013-0019
• Dostawca danych:
  Platforma Otwartych Czasopism Naukowych UAM
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