کانی‌شناسی، کانه‌زایی و زمین‌شیمی سنگ‌های آتشفشانی و نفوذی در منطقه مجیدآباد، اهر (استان آذربایجان شرقی- شمال‌غرب ایران)

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه علوم زمین، دانشکده علوم طبیعی، دانشگاه تبریز، تبریز، ایران

چکیده

منطقه مجیدآباد در 32 کیلومتری شمال‌شرق شهرستان اهر، استان آذربایجان‌شرقی و شمال‌غرب ایران واقع است. این منطقه از نظر تقسیم‌بندی ساختاری- زمین ساختی در پهنه البرز قرار دارد و بخشی از لبه پایانی نوار آتشفشانی ارومیه- دختر است. واحدهای تشکیل‌دهنده منطقه شامل سنگ‌های آذرین و آذرآواری ائوسن با ترکیب آندزیتی، تراکی‌آندزیت تا تراکی‌بازالتی و توده‌های نفوذی الیگوسن با ترکیب مونزودیوریتی و گابرویی هستند. در اثر فرآیندهای گرمابی شکل گرفته از این توده‌های نفوذی و با نفوذ آنها در واحدهای رسوبی- آتشفشانی ائوسن، دگرسانی‌های گسترده‌ای (فیلیک، آرژیلیک، پروپیلیتیک و سیلیسی) در منطقه رخ داده است. کانه‌زایی بشکل پراکنده و رگه- رگچه‌ای بوده که در دو مرحله جداگانه درون‌زاد و برو‌ن‌زاد رخ داده است. کانی‌های درون‌زاد شامل پیریت و کالکوپیریت هستند که با کانی‌های برون‌زاد کالکوسیت، کوولیت، دیژنیت، هماتیت، لیمونیت و مالاکیت همراهی می‌شوند. سری‌های آتشفشانی و نفوذی منطقه خاستگاه مشترکی داشته و در گستره آهکی قلیایی پتاسیم بالا و شوشونیتی قرار دارند و از نظر شاخص اشباع از آلومین در گستره پرآلومین و متاآلومین واقع هستند. نمودارهای چندعنصری بهنجار شده با کندریت نشان ‌دهنده غنی‌شدگی از عناصر خاکی نادر سبک (LREE) و تهی‌شدگی از هناصر خاکی نادر سنگین (HREE) است. واحد‌های سنگی منطقه در محیط‌های زمین‌ساختی کمان قاره‌ای قرار گرفته‌اند. 

کلیدواژه‌ها


عنوان مقاله [English]

Mineralogy, mineralization and geochemistry of volcanic and intrusive rocks in Majidabad region, Ahar (East Azarbaijan Province – Northwest of Iran)

نویسندگان [English]

  • Haniye Babai
  • Seyed Ghafour Alavi
  • Vartan Simmonds
Department of Earth Sciences, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
چکیده [English]

The target area is located in the northwest of Iran, East Azarbaijan Province, about 32 km northeast of Ahar. In terms of structural-tectonic division, this region is located in the Alborz zone and is a part of the end margin of Urmia-Dokhtar volcanic belt. The constituent units of the region include Eocene igneous and pyroclastic rocks with andesite, trachy-andesite to trachy-basalt composition and Oligocene intrusive masses with monzodiorite and gabbro composition. As a result of the hydrothermal processes, formed from these intrusive masses and their infiltration in the Eocene sedimentary-volcanic units, extensive alterations have occurred in the region. Mineralization is scattered and vein-veinlet, which occurred in two separate stages, hypogene and supergene. Hypogene minerals include pyrite and chalcopyrite minerals, which are accompanied by supergene minerals chalcocite, covellite, digenite, hematite, limonite and malachite. Volcanic and intrusive series of the region have a common origin and are in the range of high potassium calc-alkaline and shoshonite, and in terms of aluminum saturation index, they are in the range of peraluminous and metaaluminous. Chondrite-normalized multi-element diagrams show LREE enrichment and HREE depletion. The rock units of the region are located in the tectonic environments of the continental arc.

کلیدواژه‌ها [English]

  • mineralogy
  • mineralization
  • volcanic rocks
  • intrusive masses
  • Majidabad
[1] Innocenti F., Mazzuoli R., Pasquare G., Radicati di Brozolo F., Villari L., “Tertiary and quaternary volcanism of the Erzurumkars area (Eastern Turkey): geochronological data and geodynamic evolution”, Journal of Volcanology and Geothermal Research, 13 (1982) 223-240.
[2] Hezarkhani A., “Petrology of the intrusive rocks within the Sungun porphyry copper deposit, Azerbaijan, Iran”, Journal of Asian Earth Sciences, 27(3) (2006) 326-340.
[3] Dilek Y., Imamverdiyev N., Altunkaynak, S., "Geochemistry and tectonics of Cenozoic volcanism in the Lesser Caucasus (Azerbaijan) and the peri-Arabian region: Collision-induced mantle dynamics and its magmatic fingerprint", International Geology Review 52(2010) 536-578.
[4] Dercourt J.E., Zonenshain L.P., Ricou L.E., Kazmin V. G., Le Pichon X., Knipper A.L., Grandjacquet C., Sbortshikov I.M., Geyssant J., Lepvrier C., Pechersky D.H., “Geological evolution of the Tethys belt from the Atlantic to the Pamirs since the Lias”, Tectonophysics, 123(1-4) (1986) 241-315.
[5] Alavi M., “Structures of the Zagros fold-thrust belt in Iran”, American Journal of science, 307(9) (2007) 1064-1095.
[6] Jamali H., Dilek Y., Daliran F., Yaghubpur A., Mehrabi B., “Metallogeny and tectonic evolution of the Cenozoic Ahar–Arasbaran volcanic belt, northern Iran”, International Geology Review, 52(4-6) (2010)  608-630.
[7] Ghorbani M., “A summary of geology of Iran, In The Economic Geology of Iran”, Springer, Dordrecht, 45-64 (2013).
[8] Jamali H., Mehrabi B., “Relationships between arc maturity and Cu–MO–Au porphyry and related epithermal mineralization at the Cenozoic Arasbaran magmatic belt”, Ore Geology Review 31 (2015) 123–138.
[9] Simmonds V., Calagari A. A., Kyser K., "Fluid inclusion and stable isotope studies of the Kighal porphyry Cu–Mo prospect, East- Azarbaidjan, NW Iran", Arabian Journal of Geosciences 8 (2015) 473-453.
[10] Simmonds V., Moazzen M., "Re-Os dating of molybdenites from Oligocene Cu-Mo-Au mineralized veins in the Qarachilar area, Qaradagh batholith (northwest Iran): Implications for understanding Cenozoic mineralization in South Armenia, Nakhchivan, and Iran", International Geology Review 57 (2015) 290-304.
[11] Calagari A. A., “Fluid inclusion studies in quartz veinlets in the porphyry copper deposit at Sungun, East-Azarbaidjan, Iran”, Journal of Asian Earth Science 23 (2004) 179–189.
[12] Mohamadi M., Borna B., “Report of Geology and Drilling in the Masjed Daghi Area”, (National Iranian Copper Industries Company (NICICO)) (2006).
[13] Zarnab Company, “Geology and Alteration Studies of the Haftcheshmeh Area (National Iranian Copper Industries Company (NICICO))”, (2007).
[14] Ebrahimi S., Alirezaei S., Pan Y., “Geological setting, alteration, and fluid inclusion characteristics of Zaglic and Safikhanloo epithermal gold prospects, NW Iran”, Geological Society, London, Special Publications 350(1) (2011) 133-147.
[15] Alirezaei S., Ebrahimi S., Pan Y., “Fluid Inclusion Characteristics of Epithermal Precious Metal Deposits in the Arasbaran Metallogenic Zone, Northwestern Iran”, [extended abs.], ACROFI-II, India (2008) 1–4.
[16] Nabavi M.H., "An introduction to the Iranian geology (in Persian)", Geological Survey of Iran, (1976) 110p.
[17] Babakhani A.R., Lesquyer J.L., Rico R., “Geological map of Ahar quadrangle (scale 1:250,000): Geological Survey of Iran”, Tehran, Iran (1990).
[18] Mehrpartou M., Kh. Nazer N., “Geological map of Kaleybar (scale 1:100.000)”, Geology survey of Iran, Tehran, Iran (in Persian) (1999).
[19] Whitney D. W., Evans B. W., “Abbreviations for names of rock forming minerals”, American Mineralogist 95 (2010) 185-187.
[20] Middlemost E.A.K., “Naming materials in the magma igneous system”, Earth-Science Reviews 37 (1994) 215–224.
[21] Winchester J.A., Floyd P.A., “Geochemical classification of different magma series and their differentiation products using immobile elements”, Chemical Geology, 20 (1977) 325-343.
[22] Hastie A.R., Kerr A.C., Pearce J.A., Mitchell S.F., "Classification of altered volcanic island arc rocks using immobile trace elements", development of the Th-Co discrimination diagram. Journal of Petrology 48(2007) 2341-2357.
[23] Maniar P.D., Piccoli P.M., “Tectonic discrimination of granitoids, Geological Society if America Bulletin”, 101(5) (1989)  635-643.
[24] Wilson M., “Igneous petrogenesis, a global tectonic approach”, Chapman and Hall, 466 p. (1989).
[25] Krauskopf K. P., Bird D., “Introduction to geochemistry”, Mc Graw Hill, 788 pp. (1976).
[26] Winter J.D., “An Introduction to Igneous and Metamorphic Petrology”, Prentice Hall Inc., Upper Saddle River, NJ, 697p. (2001).
[27] Ying J., Zhang H., Sun M., Tang Y., Zhou X., “Petrology and geochemistry of zijinshan alkalin intrusive complex in shanxi Province, Western north China Craton: Implication for magma mixing of different sources in an extensional regime”, Lithos, v. 01566 (2007) p. 1- 22.
[28] Boynton W. V., "Geochemistry of the rare earth elements: meteorite studies. In: Henderson, P. (ed), Rare Earth Element Geochemistry", Elsevier (1984) 63-114.
[29] Rollinson H.R., “Using Geochemical Data: Evaluation, Presentation, Interpretation. Routledge”, London, 384 p. (2014)
[30] Jung S., Hffer E., Hoernes S., “Neo-Proterozoic rift-related syenites (North Damara Belt, Namibia): Geochemical and Nd-Sr-PB-O istope constraints for mantle sources and petrogenesis”, Lithos, v. 96 (2007) p. 415-435.
[31] Wass S.Y., Roger N.W., “Mantle Metasomatism-Precursor to alkaline continental volcanism. Geochim”, Cosmochim. Acta, v. 44, p. (1980) 1811-1823.
[32] Müller D., Rock N. M. S., Groves D. I., “Geochemical discrimination between shoshonitic and potassic volcanic rocks in different tectonic settings: a pilot study”, Mineralogy and Petrology 46 (1992) 259–289.
[33] Wood D. A., “The application of a Th-Hf-Ta diagram to problems of tectenomagmatic classification and to establishing the nature of crustal contamination of basaltic lavas of the British tertiary volcanic province”, Earth Planet Sci Lett (50), (1980) Pp. 11-30.