نشریه علوم زمین خوارزمی

نشریه علوم زمین خوارزمی

زایش مگنتیت کلیدی بر شناخت شرایط فیزیکوشیمیایی تشکیل کانسارهای مس ـ مولیبدن پورفیری؛ منطقه مطالعاتی کانسار پورفیری میدوک

نویسندگان
1 دانشگاه شهید چمران اهواز
2 دانشگاه لرستان
چکیده
کانسار پورفیری مس ـ مولیبدن میدوک در بخش جنوبی کمان ماگمایی ارومیه ـ دختر و در محدوده کمربند ماگمایی سنوزوئیک کرمان واقع شده است. این کانسار به‌واسطه حضور گسترده مگنتیت به‌عنوان یکی از کانی‌های فرعی در زون‌های دگرسانی پتاسیک و زون انتقالی بین زون پتاسیک و فیلیک، بستری مناسب برای تحلیل‌های ژئوشیمیایی فراهم کرده است. در این پژوهش، به‌منظور بررسی شرایط فیزیکوشیمیایی حاکم بر تشکیل مگنتیت‌ها، نمونه‌­های انتخاب شده توسط دستگاه EPMA آنالیز شدند. نتایج تجزیه عنصری نشان داد که مگنتیت‌های منطقه با غلظت بالای Ti و V و مقدار نسبتاً پایین Al و Mn، عمدتاً منشأ گرمابی داشته و در شرایط دمایی 200 تا 300 درجه سانتی‌گراد و فوگاسیته اکسیژن نسبتاً پایین شکل گرفته‌اند. ترکیب شیمیایی این کانی‌ها به‌ویژه نسبت Ti/V و پراکندگی عناصر فرعی نظیر Co، Ni و Cr، توانست به‌خوبی تمایز میان مگنتیت‌های ماگمایی و گرمابی را نشان دهد. تحلیل نمودارهای مختلف نیز تأیید کرد که مگنتیت‌های مورد مطالعه در محدوده مشخصه کانسارهای پورفیری قرار دارند. براساس شواهد پتروگرافی، پراکندگی مگنتیت همراه با کانی‌های سولفیدی نظیر کالکوپیریت و پیریت، همخوانی کامل با نتایج شیمیایی دارد. این پژوهش نشان می‌دهد که شیمی مگنتیت می‌تواند به‌عنوان ابزار مؤثری در شناسایی و مدل‌سازی فرآیندهای کانه‌زایی در سیستم‌های پورفیری به کار رود و راهگشای توسعه روش‌های نوین اکتشاف در ذخایر پنهان و یا عمقی باشد.



کلیدواژه‌ها

عنوان مقاله English

Formation of magnetite as a key indicator for understanding the physicochemical conditions of porphyry Cu ـ Mo deposit formation: A case study from the Meiduk porphyry deposit in Kerman Province, southeastern Urumieh-Dokhtar zone

نویسندگان English

Adel Saki 1
Peyman Eskandarnia 2
Alireza Zarasvandi 1
Naval Malohi 1
1 Shahid Chamran University of Ahvaz
2 Lorestan University
چکیده English

The Meiduk porphyry Cu ـ Mo deposit is located in the southern part of the Urumieh–Dokhtar magmatic arc within the Cenozoic magmatic belt of Kerman, Iran. Due to the widespread occurrence of magnetite as a minor phase in potassic and phyllic alteration zones, this deposit provides a suitable context for geochemical investigations. In this study samples were analyzed using Electron Probe Micro-Analyzer (EPMA) to assess the physicochemical conditions of magnetite formation. Elemental data indicate that the magnetites are predominantly of hydrothermal origin, characterized by high Ti and V and relatively low Al and Mn contents. These compositions suggest formation temperatures of 200–300°C. The chemical composition, especially Ti/V ratios and trace element distributions such as Co, Ni, and Cr, effectively distinguishes between magmatic and hydrothermal magnetites. Geochemical plots confirm that the studied magnetites fall within the porphyry field. Petrographic evidence, including the occurrence of magnetite in association with sulfide minerals such as chalcopyrite and pyrite, strongly supports the geochemical findings. This study highlights the potential of magnetite chemistry as a powerful tool for deciphering ore-forming processes in porphyry systems and demonstrates its applicability in exploration and modeling of concealed or deep-seated mineral deposits.

کلیدواژه‌ها English

Urumieh–Dokhtar magmatic arc
Meiduk porphyry
EPMA
Magnetite
Agard, P., Omrani, J., Jolivet, L., Whitechurch, H., Vrielynck, B., Spakman, W., MoniÉ, P., Meyer, B., Wortel, R., 2011. Zagros orogeny: a subduction-dominated process. Geological Magazine 148, 692-725.
Alavi, M., 2004. Regional Stratigraphy of the Zagros Fold-Thrust Belt of Iran and its Proforeland Evolution. American Journal of Science January 304.
Alavi, M., 2007. Structures of the Zagros fold-thrust belt in Iran. American Journal of Science - American Jornal of Scince 307, 1064-1095.
Arabzadeh Bani Asadi, M., Ghasemi, H., Angiboust, S., Rezaei Kahkhaei, M., Lambrini, P., 2023. Chemical composition of biotite in the Gowd-e-Howz (Siah-Kuh) granitoid stock, Baft, Kerman: Evidence for tectonic setting and physicochemical conditions of magma emplacement and crystallization. Kharazmi Journal of Earth Sciences 9, 197–224.
Asadi, S., Moore, F., Zarasvandi, A., 2014. Discriminating productive and barren porphyry copper deposits in the southeastern part of the central Iranian volcano-plutonic belt, Kerman region, Iran: A review. Earth-Science Reviews 138, 25-46.
Balan, E., De Villiers, J.P.R., Eeckhout, S.G., Glatzel, P., Toplis, M.J., Fritsch, E., Allard, T., Galoisy, L., Calas, G., 2006. The oxidation state of vanadium in titanomagnetite from layered basic intrusions. American Mineralogist 91, 953-956.
Barens, S.J., Roeder, P.L., 2001. The Range of Spinel Compositions in Terrestrial Mafic and Ultramafic Rocks. Journal of Petrology 42, 2279-2302.
Berberian, F., Berberian, M., 1981. Tectono-plutonic episodes in Iran. American Geophysical Union. Geodynamic Series 3, 5-33.
Carew, M., Mark, G., Oliver, N., Pearson, N., 2006. Trace element geochemistry of magnetite and pyrite in Fe oxide (+/-Cu-Au) mineralized systems: Insights into the geochemistry of ore-forming fluid. Geochimica Et Cosmochimica Acta - Geochimica et Cosmochimica Acta 70.
Canil, D., Grondah, C., Lacourse, T., Pisiak, L.K., 2016. Trace elements in magnetite from porphyry Cu–Mo–Au deposits in British Columbia, Canada. Ore Geology Reviews 72,1116–1128
Cooke, D.R., Baker, M., Hollings, P., Sweet, G., Chang, Z., Danyushevsky, L., Gilbert, S., Zhou, T., White, N.C., Gemmell, J.B., Inglis, S., 2014. New advances in detecting the distal geochemical footprints of porphyry systems—Epidote mineral chemistry as a tool for vectoring and fertility assessments. In: Kelley, K.D., Golden, H.C. (Eds.), Building Exploration Capability for the 21st Century. Society of Economic Geologists, Littleton, Colorado, SpeciL Publication 18, 127–152.
Dare, S.A.S., Barnes, S.-J., Beaudoin, G., Méric, J., Boutroy, E., Potvin-Doucet, C., 2014. Trace elements in magnetite as petrogenetic indicators. Mineralium Deposita 49, 785-796.
Davodi, A., Ahmadi Khalaji, A., Keshtgar, S., Eskandarnia, P., Tahmasbi, Z., 2025. Geochemistry and petrogenesis of the granitoid rocks in Mahiroud volcano–plutonic complex; southeast of Sarbisheh (eastern Iran). New Findings in Applied Geology 19.
Deditius, A.P., Reich, M., Simon, A.C., Suvorova, A., Knipping, J., Roberts, M.P., Rubanov, S., Dodd, A., Saunders, M., 2018. Nanogeochemistry of hydrothermal magnetite. Contributions to Mineralogy and Petrology 173, 46.
Dewey, J.F., Pitman, W.C., Iii, Ryan, W.B.F., Bonnin, J., 1973. Plate Tectonics and the Evolution of the Alpine System. Geological Society of America Bulletin 84, 3137-3180.
Dupuis, C., Beaudoin, G., 2011. Discriminant diagrams for iron oxide trace element fingerprinting of mineral deposit types. Mineralium Deposita 46, 319-335.
Eskandarnia, P., Saki, A., Rezaei, M., Miri, M.M., 2020. Fertility of olivine–gabbronorites of Cheshmeh Ghassaban (northeast of Alvand complex) using index elements in olivine and pyroxene minerals. In: Second National Conference on Knowledge-Based Research in Earth Sciences, Ahvaz. Sivilica Press.
Ghasemi, A., Talbot, C.J., 2006. A new tectonic scenario for the Sanandaj–Sirjan Zone (Iran). Journal of Asian Earth Sciences 26, 683-693.
Ghorbani, M., Nasiri Bezenjani, R., 2011. Slab partial melts from the metasomatizing agent to adakite, Tafresh Eocene volcanic rocks, Iran. Island Arc 20, 188-202.
Grigsby, J.D., 1990. Detrital magnetite as a provenance indicator. Journal of Sedimentary Research 60, 940-951.
Haggerty, S., 2019. Oxide mineralogy of the upper mantle. pp. 355-416.
Hassanzadeh, J., 1993. Metalogenic and tectonomagmatic events in SE sector of the cenozoic active continental mar n of central Iran (Shahre-Babak, Kerman Province). California, Los Angeles.
Hedenquist, J.W., Arribas, A., Jr., Reynolds, T.J. 1998.
Evoluton of an intrusion-centered hydrothermal system: Far Southeast-Lepanto porphyry and epithermal Cu-Au deposits, Philippines. Economic Geology 93, 373-404
Jahangiri, A., 2007. Post-collisional Miocene adakitic volcanism in NW Iran: Geochemical and geodynamic implications. Journal of Asian Earth Sciences 30, 433-447.
Karimi Shahraki, B., Ghasemi Siani, M., Gholizadeh, K., 2019. Fe–Ti oxide minerals geothermometry and oxygen fugacity at the Dar Gaz anomaly, Kahnuj. Kharazmi Journal of Earth Sciences 5, 79–98.
McInnes, B., Evans, N., Belousova, E., Griffin, W.T., Andrew, R.L., 2003. Timing of mineralization and exhumation processes at the Sar Cheshmeh and Meiduk porphyry Cu deposits, Kerman belt, Iran. Mineral Exploration and Sustainable Development, 1197-1200.
Meinert, L.D., Dipple, G.M., Nicolescu, S., 2005. World skarn deposits. In: Hedenquist, J.W., Thompson, J.F.H., Goldfarb, R.J., Richards, J.P. (Eds.), One Hundredth Anniversary Volume. Society of Economic Geologists, Littleton, Colorado, USA, 299-336.
Mohajjel, M., Fergusson, C., Sahandi, M., 2003. Cretaceous-Tertiary convergence and continental collision, Sanandaj-Sirjan Zone, Western Iran. Journal of Asian Earth Sciences 21, 397-412.
Mohammaddoost H, Ghaderi M, Kumar TV, Hassanzadeh J, Alirezaei S (2017) Zircon U–Pb and molybdenite Re–Os geochronology, with S isotopic composition of sulfdes from the Chah-Firouzeh porphyry Cu deposit, Kerman Cenozoic arc, SE Iran. Ore Geology Reviews 88, 384–399
Mollo, S., Putirka, K., Iezzi, G., Scarlato, P., 2013. The control of cooling rate on titanomagnetite composition: implications for a geospeedometry model applicable to alkaline rocks from Mt. Etna volcano. Contributions to Mineralogy and Petrology 165, 457-475.
Nadoll, P., Angerer, T., Mauk, J.L., French, D., Walshe, J., 2014. The chemistry of hydrothermal magnetite: A review. Ore Geology Reviews 61, 1-32.
Nadoll, P., Mauk, J.L., Leveille, R.A., Koenig, A.E., 2015. Geochemistry of magnetite from porphyry Cu and skarn deposits in the southwestern United States. Mineralium Deposita 50, 493-515.
Parandoush, K., Atapour, H. Riseh, M. A. 2019. Geochemical signatures of waste rocks around Sarcheshmeh porphyry copper mine dumps, southeastern Iran: Implications for exploration, economic by-products and the environment. Journal of Geochemical Exploration 199, 31-52.
Pisiak, L., Canil, D., Grondahl, C., Plouffe, A., Ferbey, T., Anderson, R.G., 2014. Magnetite as a porphyry Cu indicator mineral in till: a test using the Mount Polley porphyry Cu-Au deposit. British Columbia, Geoscience B.C. Report 2015-1, 141-149.
Richards, J.P., Spell, T., Rameh, E., Razique, A., Fletcher, T., 2012. High Sr/Y Magmas Reflect Arc Maturity, High Magmatic Water Content, and Porphyry Cu ± Mo ± Au Potential: Examples from the Tethyan Arcs of Central and Eastern Iran and Western Pakistan. Economic Geology 107, 295-332.
Rusk, B., Oliver, N., Brown, A., Lilly, R., Jungmann, D., 2009. Barren magnetite breccias in the Cloncurry region, Australia; comparisons to IOCG deposits. In: Society for Geology Applied to Mineral Deposits, 10th Biennial SGA Meeting, Townsville, Australia, 2009, Proceedings, 656–658.
Saki, A., Miri, M.M., Eskandarnia, P., Rezaei, M., Dorani, M., 2020. Petrogenesis of olivine gabbronorites from Cheshmeh-Ghassaban area (NW of Hamedan) using mineral chemistry. Petrological Journal 10, 45–66.
Shafiei, B., Haschke, M., Shahabpour, J., 2009. Recycling of orogenic arc crust triggers porphyry Cu mineralization in Kerman Cenozoic arc rocks, southeastern Iran. Mineralium Deposita 44, 265-283.
Shafiei, B., Shahabpour, J., 2008. Gold Distribution in Porphyry Copper Deposits of Kerman Region, Southeastern Iran. Journal of Sciences Islamic Republic of Iran 19, 247-260.
Shen, P., Pan, H., Zhou, T., Wang, J., 2014. Petrography, geochemistry and geochronology of the host porphyries and associated alteration at the Tuwu Cu deposit, NW China: a case for increased depositional efficiency by reaction with mafic hostrock? Mineralium Deposita 49, 709-731.
Sillitoe, R., 2010. Porphyry Copper Systems. Economic Geology 105, 3-41.
Simon, A.C., Candela, P.A., Piccoli, P.M., Mengason, M., Englander, L., 2008. The effect of crystal-melt partitioning on the budgets of Cu, Au, and Ag. American Mineralogist 93, 1437 - 1448.
Sinclair, W., 2007. Porphyry deposits. pp. 223-243.
Singoyi, B., Danyushevsky, L., Davidson, G., Large, R., Zaw, K., 2006. Determination of trace elements in magnetites from hydrothermal deposits using the LA-ICP-MS technique. Abstracts of Oral and Poster Presentations from the SEG 2006 Conference, 367-368.
Taghipour, N., 2007. The application of fluid inclusions and isotope geochemistry as guides for exploration, alteration and mineralization at the Meiduk porphyry copper deposit, Shahr-Babak, Kerman. Shaheed Bahonar University (Kerman), Iran.
Tale Fazel, E., 2023. Ilvaite trace mineral chemistry as a thermodynamic recorder of retrograde alteration and metallogenic indicator for discrimination of skarn deposits: an example from the iron deposit in north Sanandaj–Sirjan Zone. Journal of Earth Sciences 9, 283–307.
Tian, J., Zhang, Y., Gong, L., Francisco, D.G., Emil Berador, A., 2021. Genesis, geochemical evolution and metallogenic implications of magnetite: Perspective from the giant Cretaceous Atlas porphyry Cu–Au deposit (Cebu, Philippines). Ore Geology Reviews 133, 104084.
Wang, M., Gutzmer, J., Michalak, P.P., Guo, X., Xiao, F., Wang, W., Liu, K., 2014. PGE geochemistry of the Fengshan porphyry–skarn Cu–Mo deposit, Hubei Province, Eastern China. Ore Geology Reviews 56, 1-12.
Wen, G., Li, J.-W., Hofstra, A., Koenig, A., Lowers, H., Adams, D., 2017. Hydrothermal reequilibration of igneous magnetite in altered granitic plutons and its implications for magnetite classification schemes: Insights from the Handan-Xingtai iron district, North China Craton. Geochimica et Cosmochimica Acta 213.
Whalen, J.B., Chappell, B.W., 1988. Opaque mineralogy and mafic mineral chemistry of I- and S-type granites of the Lachlan fold belt, Southeast Australia. American Mineralogist 73, 281-296.
Whitney, D., Evans, B., 2010. Abbreviations for Names of Rock-Forming Minerals. American Mineralogist 95, 185-187.
Wu, C., Chen, H., Hong, W., Li, D., Liang, P., Fang, J., Zhang, L., Lai, C., 2019. Magnetite chemistry and implications for the magmatic-hydrothermal ore-forming process: An example from the Devonian Yuleken porphyry Cu system, NW China. Chemical Geology 522, 1-15.
Yang, Z. and Cooke, D. R., 2019. Chapter 5 Porphyry Copper Deposits in China. In: Chang, Z. and Goldfarb, R. J. (eds.) Mineral Deposits of China. Society of Economic Geologists.
Yang, Z., Hou, Z., White, N.C., Chang, Z., Li, Z., Song, Y., 2009. Geology of the post-collisional porphyry copper–molybdenum deposit at Qulong, Tibet. Ore Geology Reviews 36, 133-159.
Zarasvandi, A., Rezaei, M., Raith, J.G., Pourkaseb, H., Asadi, S., Saed, M., Lentz, D.R., 2018. Metal endowment reflected in chemical composition of silicates and sulfides of mineralized porphyry copper systems, UrumiehDokhtar magmatic arc, Iran. Geochimica et Cosmochimica Acta, 223: 36–59.
Zarasvandi, A., Rezaei, M., Raith, J.G., Taheri, M., Asadi, S., Heidari, M., 2023. Magnetite chemistry of the Sarkuh Porphyry Cu deposit, Urumieh–Dokhtar Magmatic Arc (UDMA), Iran: A record of deviation from the path sulfide mineralization in the porphyry copper systems. Journal of Geochemical Exploration 249, 107213.
Zhao, L., Chen, H., Zhang, L., Li, D., Zhang, W., Wang, C., Yang, J., Yan, X., 2018. Magnetite geochemistry of the Heijianshan Fe–Cu (–Au) deposit in Eastern Tianshan: Metallogenic implications for submarine volcanic-hosted Fe–Cu deposits in NW China. Ore Geology Reviews 100, 422-440.