List of Articles Biotite

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  1 - Biotite and amphibole geobarometer as an indicator of exploration potential for Cu-Fe deposits in the Panah-Kuh skarn, West of Yazd
  اعظم  زاهدی Mohammad Boomeri
  The intrusion of Panah-Kuh granodiorite-quartz diorite stock into the limestone-dolomite of the Jamal Formation has led to the skarn formation in the Panah-Kuh area. Skarns have formed in direct contact with intrusions in carbonate rocks. The Panah-Kuh granitic rocks ar More

  The intrusion of Panah-Kuh granodiorite-quartz diorite stock into the limestone-dolomite of the Jamal Formation has led to the skarn formation in the Panah-Kuh area. Skarns have formed in direct contact with intrusions in carbonate rocks. The Panah-Kuh granitic rocks are mainly metaluminous, calc-alkaline with I-type granitoid characteristics. Biotite and amphibole phenocrysts are the most abundant hydrous mineral in the Panah-Kuh granite. Chemical analysis of biotite and amphibole in granitic rocks in Panah-Kuh shows that the total Al (TAl) content of them can be used as a useful indicator for distinguishing between mineralized and nonmineralized granitic rocks. A good positive correlation is showed between the TAl content and the formation pressure of the granitic rocks estimated by biotite and hornblende geobarometers. These facts suggest that the TAl content of biotite and hornblende can be used to estimate the solidification pressure of the granitic rocks. According to the obtained biotite and amphibole geobarometers, it is estimated that Panah-Kuh Fe-Cu skarn deposit was formed at pressures of 1-2 kb similar to Yaguki, Kamaishi and Tanazawa Fe-Cu deposits in Japan. Therefore, biotite and amphibole geobarometers of granitic rocks may be a useful indicator in the exploration of skarn ore deposits related to granitic rocks. Manuscript profile
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  2 - Reconstructing physicochemical attributes using chemistry of biotite and chlorite in the Keder porphyry copper deposit, Kerman Cenozoic magmatic arc
  Majid Heydari Alireza Zarasvandi Mohsen Rezaei عادل ساکی Sina Asadi
  The Keder porphyry copper deposit is located 14 km SW of Dehej in the north-eastern of Kerman Cenozoic magmatic arc. It is associated with diorite to quartz diorite intrusions. Considering the important role of oxygen fugacity, halogen content, and temperature in the mi More

  The Keder porphyry copper deposit is located 14 km SW of Dehej in the north-eastern of Kerman Cenozoic magmatic arc. It is associated with diorite to quartz diorite intrusions. Considering the important role of oxygen fugacity, halogen content, and temperature in the mineralization efficiency of porphyry systems, the aims of present research is the investigation of these physicochemical attributes in the magmatic stage, as well as potassic alteration of Keder porphyry using biotite and chlorite chemistry. Compared with chlorite, biotite has high SiO2, K2O, TiO2 concentrations. On the other hand, Al2O3 has highest concentration in chlorite. The depletion of K2O and SiO2 are related to the formation of adularia and K-feldspar accompanying with the breakdown of biotite to chlorite. Biotite chemistry shows that the Keder intrusion is calc-alkaline in nature. Based on FeO/FeO+MgO vs MgO diagram, biotites from Keder intrusion plot within the mantle source (M) and to a lesser extent in the crustal materials field. Using the Si vs Fe2+/Fe2+ +Mg2+ diagram, secondary chlorites that replaced biotite plot collectively within clinochlore composition. Oxygen fugacities of Keder deposit occur in HM-NNO area. The investigation of geothermometry on biotites and chlorite in the Keder porphyry copper deposit shows a temperature range between 516-680° C and 180.19-369.87° C respectively. The log fH2O/fHF and log fH2O/fHCl values range between 4.57-5.77 and 4.34-4.62 that show water content is more than halogen content in Keder intrusion. According to XFe and XMg vs. XF/XOH and XCl/XOH, Cl fugacity was similar in Keder porphyry copper deposit. Finally, it seems that high temperature together with prevailing of high oxygen fugacities during potassic alteration (onset of sulfide mineralization) could be considered as important factors on low grade mineralization at Keder deposit. Manuscript profile
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  3 - Biotite mineral chemistry, geothermobarometry and the role of total Al content of biotite in distinguishing of mineralization in the Touyeh- Darvar granitoid, SW of Damghan, Eastern Alborz.
  Azin Naderi Habibolah Ghasemi Lamberini Papadopoulou
  Touyeh- Darvar granitoid pluton is situated in the south of eastern Alborz zone (45Km SW of Damghan in Semnan province). This pluton has intruded into the late Paleozoic formations (including Barut and Lalun). Based on the field observations and petrographic studies, th More

  Touyeh- Darvar granitoid pluton is situated in the south of eastern Alborz zone (45Km SW of Damghan in Semnan province). This pluton has intruded into the late Paleozoic formations (including Barut and Lalun). Based on the field observations and petrographic studies, the pluton is composed of monzonites, quartz monzonite and monzodiorite. In terms of mineralogy, the Touyeh- Darvar granitoid consists of plagioclase, orthoclase, quartz, ± hornblende and ±biotite. Accessory minerals consists of ilmenite, magnetite, zircon, apatite, titanite and pyrite. Sericite, epidote, calcite, and chlorite are considered as secondary phases. The iron-rich biotite is the most significant mafic mineral which are situated in the alkaline and anorogenic biotite fields. The total Al content of biotite in granitic rocks can be a useful indicator for distinguishing between mineralized and non-mineralized granitic rocks. The presence of mineral veins from oxides and hydroxides of iron and manganese, fluorite, barite, lead and zinc in the host rock of this pluton also confirms that the biotite composition is useful for mineralization potential study of this pluton. Applying the thermometry based on the Ti content of biotite and barometery based on total Al content of biotite resulted in calculating temperature ranges of 650–730°C and pressures lower than 1Kb for stopping the exchange and final equilibrium of this mineral in the pluton. Manuscript profile