Document Type : Original Research Paper

Authors

1 Geology department, Faculty of Science, University of Zanjan

2 Geology, Sciences, University of Zanjan

Abstract

Qarachilar Cu-Mo-Au mineralization is located within the Qaradagh batholite in the Arasbaran metalogenic zone. This area is a part of southern margin of Lesser Caucasus. Qaradagh batholite at the Qarachilar mineralization area composed of granodiorite- quartz monzodiorite (as the main phase and host rock of mineralization), diorite, quartz monzonitic stocks, apophyses of porphyritic granite and acidic to intermediate dykes. These intrusions have Upper Eocene- lower Miocene age. All of the mentioned intrusion phases have calc-alkaline to high-K calc-alkaline nature and classified as metaluminous I-type granites. The porphyritic granite apophyses and dykes, and quartz monzonitic stocks have adakitic nature and can be classified as high silica adakites. Chondrite normalized REE patterns in granodiorites- quartz monzodiorites indicate enrichment in LREE and flat trend in MREE and HREE, while porphyritic granites show steep pattern with enrichment in LREE and depletion in HREE. Based on field investigation, geological, petrological, geochemical and tectonomagmatic discrimination diagrams, it can be conclude that granodiorite- quartz monzodiorite phase was formed in active continental margin as a result of Neo-Tethyan ocean subduction beneath the Eurasia. The quartz monzonite stocks and porphyritic granites were formed in a post collisional setting from metasomatized lithospheric mantle wedge.

Keywords

References
Baghban, S., Hosseinzadeh, M. R., Moayyed, M., Mokhtari, M. A. A. and Gregory, D., 2015- Geology, mineral chemistry and formation conditions of calc-silicate minerals of Astamal Fe-LREE distal skarn deposit, Eastern Azarbaijan Province, NW Iran. Ore Geology Reviews, 68: 79- 96.
Baghban, S., Hosseinzadeh, M. R., Moayyed, M., Mokhtari, M. A. A., Gregory, D. and Mahmoudi Nia, H., 2016- Chemical composition and evolution of the garnets in the Astamal Fe-LREE distal skarn deposit, Qara Dagh- Sabalan metallogenic belt, Lesser Caucasus, NW Iran. Ore Geology Reviews, 78: 166- 175.
Barbarin, B., 1999- A review of the relationships between granitoid types, their origins and their geodynamic environments. Lithos, 46: 605- 626.
Bonin, B., 1990- From orogenic to anorogenic settings: evolution of granitoid suites after a major orogenesis. Geological Journal, 25: 261- 270.
Brunet, M. F., Korotaev, M. V., Ershov, A. V. and Nikishin, A. M., 2003- The South Caspian Basin: a review of its evolution from subsidence modelling. Sedimentary Geology, 156: 119- 148.
Calagari, A. A. and Hosseinzadeh, G., 2006- The mineralogy of copper-bearing skarn to the east of the Sungun-Chay river, East-Azarbaijan, Iran. Journal of Asian Earth Sciences, 28: 423- 438.
Calagari, A. A., 1997- Geochemical, stable isotope, noble gas, and fluid inclusion studies of mineralization and alteration at Sungun porphyry copper deposit, East Azarbaijan, Iran: Implication for genesis. Unpublished Ph.D. Thesis. Manchester University, Manchester, 537 p.
Cameron, B. I., Walker, J. A., Carr, M. J., Patino, L. C., Matias, O. and Feigenson, M. D., 2003- Flux versus decompression melting at stratovolcanoes in southeastern Guatemala. Journal of Volcanology and Geothermal Research, 119: 21- 50.
Chappell, B. W. and White, A. J. R., 1992- I- and S-type granites in Lachlan Fold Belt. Transactions of the Royal Society of Edinburgh. Earth Sciences, 83: 1- 26.
Chappell, B. W. and White, A. J. R., 2001- Two contrasting granite types: 25 years later. Australian Journal of Earth Sciences, 48: 489- 499.
Collins, W. J., Beams, S. D., White, A. J. R. and Chappell, B. W., 1980- Nature and origin of A-type granites with particular reference to south eastern Australia. Contribution to Mineralogy and Petrology, 80: 189- 200.
Cox, K. G., Bell, J. D. and Pankhurst, R. J., 1979- The interpretation of igneous rocks. Boston, George Allen and Unwin London.
Espinoza, F., Morata, D., Polve, M., Lagabrielle, Y., Maury, C. and Guivel, C., 2008- Bimodal Back-arc alkaline magmatism after ridge subduction Pliocene felsic rocks from Central Patagonia (47˚S). Lithos, 101: 191- 217.
Green, T. H. and Pearson, N. J., 1985- Experimental determination of REE partition coefficients between amphibole and basaltic to andesitic liquids at high pressure. Geochimica et Cosmochimica Acta, 49: 1465- 1468.
Harris, N. B. W., Pearce, J. A. and Tindle, A. G., 1986- Geochemical characteristics of collision zone magmatism. Geological Society Special Publication, 19: 67- 81
Hofmann, A. W., 1988- Chemical differentiation of the earth: the relationship between mantle, continental crust, and oceanic crust. Earth and Planetary Science Letters, 90: 297- 314.
Hou, Z., Zhang, H., Pan, X. and Yang, Z., 2011- Porphyry Cu (–Mo–Au) deposits related to melting of thickened mafic lower crust: examples from the eastern Tethyan metallogenic domain. Ore Geology Reviews, 39: 21- 45.
Irvine, T. N. and Baragar, W. R. A., 1971- A guide to the chemical classification of the common volcanic rocks. Canadian Journal of Earth Science, 8: 523- 276.
Kamber, B. S., Ewart, A., Collerson, K. D., Bruce, M. C. and McDonald, G. D., 2002- Fluid-mobile trace element constraints on the role of slab melting and implications for Archaean crustal growth models: Contributions to Mineralogy and Petrology, 144: 38- 56.
Kouhestani, H., Mokhtari, M. A. A., Chang, Z., Stein, H. J. and Johnson, C. A., 2018- Timing and genesis of ore formation in the Qarachilar Cu-Mo-Au deposit, Ahar-Arasbaran metallogenic zone, NW Iran: Evidence from geology, fluid inclusions, O-S isotopes and Re-Os geochronology. Ore Geology Reviews, 102: 757- 775.
Maniar, P. D. and Piccoli, P. M., 1989- Tectonic discrimination of granitoids. Geological Society of America Bulletin, 101: 635- 643.
Martin, H., Smithies, R. H., Rapp, R., Moyen, J. F. and Champion, D., 2005- An overview of adakite, tonalite- trondhjemite- granodiorite (TTG) , and sanukitoid: relationships and some implications for crustal evolution. Lithos, 79: 1- 24.
McDonough, W. F. and Sun, S. S., 1995- Composition of the Earth. Chemical Geology, 120: 223- 253.
Meissner, R. and Mooney, W., 1998- Weakness of the lower continental crust: a condition for delamination, uplift, and escape. Tectonophysics, 296: 47- 60.
Mokhtari, M. A. A., 2012- The mineralogy and petrology of the Pahnavar Fe skarn in the eastern Azarbaijan, NW Iran. Central European Journal of Geosciences, 4(4): 578- 591.
Mollaie, H., Pe-Piper, G. and Dabiri, R., 2014- Genetic relationships between skarn ore deposits and magmatic activity in the Ahar region, Western Alborz, NW Iran. Geologica Carpathica, 65(3): 207- 225.
Moritz, R., Rezeau, H., Ovtcharova, M., Tayan, R., Melkonyan, R., Hovakimyan, S., Ramazanov, V., Selby, D., Ulianov, A., Chiaradia, M. and Putlitz, B., 2016- Long-lived, stationary magmatism and pulsed porphyry systems during Tethyan subduction to post-collision evolution in the southernmost Lesser Caucasus, Armenia and Nakhitchevan. Gondwana Research, 37: 465- 503.
Muller, D. and Groves, D. I., 1997- Potassic igneous rocks and associated gold- copper mineralization. Second edition, Springer Verlag, 242 p.
Pearce, J. A., 1996- Sources and setting of granitic rock. Episodes, 19(4): 120- 125.
Peccerillo, A. and Taylor, S. R., 1976- Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, northern Turkey. Contribution to Mineralogy and Petrology, 58: 63- 81.
Rollinson, H. R., 1993- Using geochemical data, evaluation, presentation, interpretation. Longman, Singapore.
Simonds, V. and Moazzen, M., 2015- 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(3): 290- 304.
Srivastava, R. K. and Sigh, R. K., 2004- Trace element geochemistry and genesis of Precambrian sub-alkaline mafic dikes from the central Indian Craton: evidence for mantle metasomatism. Journal of Asian Earth Sciences, 23: 373- 389.
Sun, S. S., McDonough, W. F., 1989- Chemical and isotopic systematics of oceanic basalts: Implications for mantle composition and processes. Geological Society of London, Special Publication, 42: 313- 345.
Taylor, S. R. and McLennan, S. M., 1985- The continental crust: its composition and evolution. Blackwell Scientific Publication, Oxford.
Turner, S., Arnaud, N., Liu, J., Rogers, N., Hawkesworth, C., Harris, N., Kelley, S., Van Calsteren, P. and Deng, W., 1996- Post-collision, shoshonitic volcanism on the Tibetan, Plateau: implications for convective thinning of the lithosphere and source of ocean island basalts. Journal of Petrology, 37: 45- 71.
Wang, K. L. and Chung, S. L., 2004- Geochemical constraints for the genesis of post-collisional magmatism and the geodynamic evolution of the northern Taiwan region. Journal of Petrology, 45: 975- 1011.
Wilson, M., 1989- Igneous Petrogenesis. Chapman and Hall, London.
Wu, F., Jahnb, B., Wildec, S.A., Lod, C. H., Yuie, T. F., Lina, Q., Gea, W. and Suna, D., 2003- Highly fractionated I-type granites in NE China II: isotopic geochemistry and implications for crustal growth in the Phanerozoic. Lithos, 67: 191-204.
Zheng, T. Y., Zhao, L., Xu, W. W. and Zhu, R. X., 2008- Insight into modification of North China Craton from seismological study in the Shandong Province. Geophysical Research Letters, 35(22): 1- 5