TY - JOUR ID - 58253 TI - geology, petrography, mineralization and fluid inclusion studies in the mesgarabad exploration area, southeast of tehran JO - Scientific Quarterly Journal of Geosciences JA - GSJ LA - en SN - 1023-7429 AU - Norouzi, M AU - Lotfi, M. AU - Emami, M. H. AU - Jamali, H. AU - Abedini, A. AD - M.Sc., Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran AD - Associate Professor, Research Institute for Earth Sciences, Geological Survey of Iran; Islamic Azad University, North-Tehran Branch, Tehran, Iran AD - Associate Professor, Research Institute for Earth Sciences, Geological Survey of Iran; Islamic Azad University, Islamshahr Branch, Islamshahr, Iran AD - Assistant Professor, Department of Geology, Faculty of Science, University of Isfahan, Isfahan, Iran AD - Associate Professor, Department of Geology, Sciences Faculty, Urmia University, Urmia, Iran Y1 - 2018 PY - 2018 VL - 27 IS - 106 SP - 243 EP - 256 KW - Subvolcanic intrusive bodies KW - Epithermal KW - Skarn KW - Garnet KW - Fluid Inclusions KW - Mesgarabad Area KW - Tehran KW - Iran DO - 10.22071/gsj.2018.58253 N2 - Mesgarabad area is located in ~10 km southeast of Tehran, the Central- Alborz structural zone (CASZ) of Iran. The rock units exposed in the area consist of Eocene volcanics, volcano-sedimentary and sedimentary rocks intruded by post upper Eocene granodiorite to quartz monzo-diorite. These subvolcanic intrusive bodies show porphyroid to microgranular textures and have calc-alkaline magmatic nature. These bodies produced hydrothermal fluids causing extensive alteration zones developed along the Se-Darreh-e-Bozorg strike-slip fault. The effects of hydrothermal fluids on the entire Eocene rock units and subvolcanic intrusive bodies are remarkable. The main alterations are silicification, sericitization, chloritization, epidotizaton, actinolitization, argillization, carbonatization, and alunitization-jarositization, which provided suitable physico-chemical conditions for ore-mineralization. The penetration of subvolcanic intrusive bodies into the Eocene volcanics, volcano-sedimentary and sedimentary rocks brought about skarn mineralization and epithermal barite veins. Microscopic studies and advanced analysis showed that the principal mineral phases in the epithermal zones are magnetite, pyrite, chalcopyrite, bornite, chalcocite, barite, Cu+Sn+Fe alloy, hematite, psilomelane, jacobsite, martite, geothite, and lepidochrosite. The skarnification processes occurred at two distinct stages, (1) progressive and (2) retrogressive. The pyrometasomatic anhydrous minerals such as andradite-grossularite formed during progressive stage and the hydrous minerals like epidote, chlorite, tremolite- actinolite, calcite, quartz, pyrite, chalcopyrite and chalcocite were developed during retrogressive stage. Fluid inclusion studies on primary aqueous inclusions trapped in barite crystals revealed fluid that mixing of two fluids having different physico-chemical conditions played an important role for ore deposition. UR - http://www.gsjournal.ir/article_58253.html L1 - http://www.gsjournal.ir/article_58253_c454a195cd7edd98965063bb99815267.pdf ER -