نویسندگان
1 گروه زمین شناسی، واحد خرم آباد، دانشگاه آزاد اسلامی، خرم آباد، ایران
2 گروه زمین شناسی، واحد الیگودرز، دانشگاه آزاد اسلامی، الیگودرز، ایران
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
The intrusive mass of Mesteroon area is located in the north of Aligudarz and is part of the Sanandaj-Sirjan magmatic-metamorphic zone. This mass is granodiorite with S-C fabrique. This mass contains megacrysts of quartz, alkali-feldspar, plagioclase, biotite and muscovite flakes. Biotites are brown and reddish-brown in color and have curvature and often show kingband phenomenon due to stress. Mineral chemistry studies show that the composition of biotites is rich in magnesium and includes the siderophyllite-anite end member, and they are placed in the range of biotite and outside the range of phlogopite. Also, the biotites of the Mestroon area are often primary and magmatic, and none of them are in the range of newly balanced biotites. The average formation temperature of biotites is 638.48°C and it is between 659.99°C and 753.20°C. The range of pressure changes in the Mestron area with an average of 3.32 kb indicates the formation of biotites at a depth of less than 3 km and is consistent with the pressure obtained in the biotite pressure gauge calibration curve for granite rocks. The biotites of Mesteroon area are located in the biotite range of subduction calc-alkaline rocks and in the type I orogenic zone and have been confirmed with the help of whole rock data. The high Fe/Mg ratio in biotites indicates the magnetite nature of Mesteroon granitoids. The values of Fe# of biotites against Al with an average of 2.3 as the FQM average are also in the range of magnetite series granitoids and indicate the magma's oxide conditions. The amount of oxygen fugacity in Mesteroon area is high with the help of available data and it is estimated to be 10-10 to 10-12 bar, which is a suitable environment for gold and copper mineralization in epithermal and porphyry systems.
کلیدواژهها [English]
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