List of Articles شیمی کانی

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  1 - Study of mineral chemistry, geothermobarometry and tectonic setting of gabbroic rocks from north-west Hamedan, Iran
  عادل ساکی Hooshang Pourkaseb Alireza Zarasvandi Milad Jahani Maryam Dorani
  The study area is geologically located in the northern area of the Sanandaj-Sirjan metamorphic zone. Based on petrographic study, the main minerals consists of plagioclase, pyroxene, amphibole and biotite and the accessory minerals are chlorite, muscovite, ilmenite and More

  The study area is geologically located in the northern area of the Sanandaj-Sirjan metamorphic zone. Based on petrographic study, the main minerals consists of plagioclase, pyroxene, amphibole and biotite and the accessory minerals are chlorite, muscovite, ilmenite and zircon. The obtained results from the mineral chemistry in this study indicate that the amphiboles are calcic amphiboles, and in terms of chemical composition they can be called pargasit, tschermakite and magnesiohomblende. Plagioclases are also andesian. Due to the low Na2O content, it can be concluded, that tectonically these amphiboles are of S-Amph type and are related to the subduction zones. Based on the high levels of Al2O3, the origin of amphiboles is mantle-type. Therefore, due to the ratio of Fetot (Fetot + Mg+2) to AlIv, which is less than 0.6, the oxygen fugacity was high. On the other hand, the water levels vary from 2 to 2.3 for hornblende crystallization. Different methods were used to perform thermobarometry, the best of which showed that the formation temperature of gabbroic mass has been in the range of 700°C (in average) and a pressure of 4.45- 7.52 Kb. According to the estimated pressures, the magma was originated at a depth of 25-30 Km, which is near the Moho discontinuity. Manuscript profile
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  2 - Mineralogy and mineral chemistry of Pb- Ag- (Zn-Cu-Ba) Ravanj mining district, North of Delijan
  Majid Ghasemi siani Fateme Isaabadi
  The Ravanj ore deposit in the North of Delijan formed in the sedimentary host rocks. This ore mineralization system is controlled by normal faults, and mineralization occurs as massive, laminate, open space fillings, breccia and hydrothermal vein/veinlets ore bodies con More

  The Ravanj ore deposit in the North of Delijan formed in the sedimentary host rocks. This ore mineralization system is controlled by normal faults, and mineralization occurs as massive, laminate, open space fillings, breccia and hydrothermal vein/veinlets ore bodies consisting of galena, sphalerite, fahlore group minerals, pyrite, chalcopyrite, dolomite, calcite, ankerite, barite, and quartz. Sulfide ore mineralization occurred within two mineralization horizons consisting of the massive-breccia ore horizon hosted by massive upper limestone (Km2) and layered sulfide ore horizon in middle shale (Ks2) and lower thin bedded limestone (Km1) as syn-sedimentary to epigenetic mineralization. Dolomitization is the main alteration related to mineralization and occurs adjacent to normal fault and consists of diagenetic and two hydrothermal dolomites. Hydrothermal dolomites are rich in iron. The ankrite shows that the ore hydrothermal fluid was Fe-rich. Chemistry of galena II and sphalerite II show that these minerals have a tendency to tetrahedrite-tennantite side which are consistent with presence of fahlore mineral incluisions in the microscopic studies. High Cd content in sphalerite and the presence of acanthite show that fluid mineralization had low temperature. According to the evidence such as mineralogy, mineral chemistry, ore texture and structures, and structural studies and combining these results with geochemistry, fluid inclusion and isotope geochemistry, the Ravanj ore deposit can be considered as an Irish-type Zn- Pb deposit. Manuscript profile