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چکیده
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Abstract: The study area is part of Kasnazan- Qolqoleh shear zone that is located in southwest of Saqqez in west of Iran. It consists of a part of an orogenic belt in western part of Iran. It is the result of closure of Neo-Tethys during CretaceousTertiary continental collision between the Afro-Arabian plate beneath central Iran. This zone hosted several orogenic gold deposits and occurrences, including the Qolqoleh, Kervian, Qabaglojeh, Hamzeh- Gharanein, Gharechar, and Kasnazan mineralization, which are related to the major SaqqezSardasht thrust.According to the geological maps of Saqqez, the main units belong to the Percambrian- Paleozoic rocks and included chlorite schist, marble and mylonitized granite. Host rocks of gold mineralization are mostly chlorite schist, metagranite, and mylonitic granite in across Kasnazan- Qolqoleh shear zone. Based on microscopic studies, chlorite mica schist in Qolqoleh and Qabaghlojeh is mainly included chlorite around 20-60%, quartz (30-35%), plagioclase (20- 25%), biotite (5- 0%), sericite (15- 20%), and carbonate (5%). Metagranite in Hamzeh-Gharanein mainly includes quartz, alkali feldspar, plagioclase, and biotite with accessory minerals zircon, rutile, apatite, sericite, and iron oxide.In this study, we have evaluated in situ dating of rutile by LA- ICPMS. The U-Pb analyses were carried out at the University of New Brunswick in Canada, using a Resonetics 193 nm Excimer laser coupled to an Agilent 7700X quadrupole ICP- MS. Rutile were analyzed in standard 30- m- thick polished thin sections. Only minerals free of inclusions were used. Despite its common occurrence, rutile has so far received less attention as a geochronometer than zircon and monazite, because of the low U concentration in many rutile (as low as <0.01 ppm). To solve this problem, we chose grains with
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