Document Type : Original Research Paper
Author
Department of Geology, Faculty of Science, Mohaghegh Ardabili University, Ardabil, Iran
Abstract
In the north of Ardabil (from Namin to Lahroud) there are widespread sequences of Eocene and Quaternary mafic to intermediate and felsic magmatic activities with different compositions. The composition of these rocks varies from basaltic lavas as well as dacitic and rhyolitic domes in Namin to basalt and basaltic andesite in Lahroud area. The chemical composition of olivine from olivine basaltic lavas indicates a forsterite composition changing from 67.8 to 92.7. Clinopyroxenes show diopside composition whereas plagioclase has labradorite to bytownite composition. Garnet xenocrysts in the rhyolitic domes have an almandine composition. These rocks are characterized by the enrichment in LREEs compared to the HREEs. Mafic-intermediate rocks show shoshonitic to high-K calc-alkaline composition whereas dacitic and rhyolitic domes show adakitic signature. Geochemical and isotopic characteristics of basaltic-andesitic rocks indicate their genesis are related to the partial melting of a metasomatized mantle wedge, re-fertilized by sediments and fluids from the subducting slab in the Eocene subduction zone of Iran. The geochemical and isotopic signatures of dacitic-rhyolitic domes indicate their origin from partial melting of the lower parts of the thickened continental crust of Iran.
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Aghazadeh, M., Castro, A., Badrzadeh, Z., and Vogt, K., 2011. Post-collisional polycyclic plutonism from the Zagros hinterland: the Shaivar Dagh plutonic complex, Alborz belt, Iran. Geological Magazine, 148, 980-100, doi: 10.1017/S0016756811000380.
Aghazadeh, M., Hou, Z.Q., Badrzadeh, Z., and Zhou, L.M., 2015. Temporal-spatial distribution and tectonic setting of porphyry copper deposits in Iran: Constraints from zircon U-Pb and molybdenite Re-Os geochronology. Ore Geology Reviews, 70, 385-406, doi: 10.1016/j.oregeorev.2015.03.003.
Allen, M.B., and Armstrong, H.A., 2008. Arabia–Eurasia collision and the forcing of mid-Cenozoic global cooling. Palaeogeography, Palaeoclimatology, Palaeoecology, 265, 52-58,doi: 10.1016/j.palaeo.2008.04.021.
Ardila, A.M.M., Paterson, S.R., Memeti, V., Parada, M.A., and Molina, P.G., 2019. Mantle driven cretaceous flare-ups in Cordilleran arcs.Lithos, 326, 19-27, doi: 10.1016/j.lithos.2018.12.007.
Ashrafi, N., Hasebe, N., and Jahangiri, A., 2018. Cooling history and exhumation of the Nepheline Syenites, NW Iran: Constraints from Apatite fission track. Iranian Journal of Earth Sciences, 10, 109-120.
Billen, M.I., and Arredondo, K.M., 2018. Decoupling of plate-asthenosphere motion caused by non-linear viscosity during slab folding in the transition zone.Physics of the Earth and Planetary Interiors, 281, 17-30, doi: 10.1016/j.pepi.2018.04.011.
Chiaradia, M., 2009. Adakite-like magmas from fractional crystallization and melting-assimilation of mafic lower crust (Eocene Macuchi arc, Western Cordillera, Ecuador). Chemical Geology, 265, 468-487, doi: 10.1016/j.chemgeo.2009.05.014.
Defant, M., Jackson, T., Drummond, M.d., De Boer, J., Bellon, H., Feigenson, M., Maury, R., and Stewart, R., 1992. The geochemistry of young volcanism throughout western Panama and southeastern Costa Rica: an overview. Journal of the Geological Society, 149, 569-57, doi: 10.1144/gsjgs.149.4.0569.
Drummond, M.S., and Defant, M.J., 1990. A model for trondhjemite‐tonalite‐dacite genesis and crustal growth via slab melting: Archean to modern comparisons. Journal of Geophysical Research: Solid Earth, 95, 21503-21521, doi: 10.1029/JB095iB13p21503.
Duggen, S., Portnyagin, M., Baker, J., Ulfbeck, D., Hoernle, K., Garbe-Schonberg, D., and Grassineau, N., 2007. Drastic shift in lava geochemistry in the volcanic-front to rear-arc region of the Southern Kamchatkan subduction zone: Evidence for the transition from slab surface dehydration to sediment melting. Geochimica Et Cosmochimica Acta, 71, 452-480, doi: 10.1016/j.gca.2006.09.018.
Farner, M.J., and Lee, C.-T.A., 2017. Effects of crustal thickness on magmatic differentiation in subduction zone volcanism: A global study. Earth and Planetary Science Letters, 470, 96-107, doi: 10.1016/j.epsl.2017.04.025.
Hastie, A.R., Kerr, A.C., Pearce, J.A., and Mitchell, S., 2007. Classification of altered volcanic island arc rocks using immobile trace elements: development of the Th–Co discrimination diagram. Journal of Petrology, 48, 2341-2357, doi: 10.1093/petrology/egm062.
Iveson, A.A., Rowe, M.C., Webster, J.D., and Neill, O.K., 2018. Amphibole-, Clinopyroxene- and Plagioclase-Melt Partitioning of Traceand Economic Metals in Halogen-Bearing Rhyodacitic Melts. Journal of Petrology, 59, 1579-1604, doi: 10.1039/petrology/egy072.
Jacques, G., Hoernle, K., Gill, J., Hauff, F., Wehrmann, H., Garbe-Schönberg, D., van den Bogaard, P., Bindeman, I., and Lara, L.E., 2013. Across-arc geochemical variations in the Southern Volcanic Zone, Chile (34.5–38.0 S): constraints on mantle wedge and slab input compositions. Geochimica et Cosmochimica Acta, 123, 218-243, doi: 10.1016/j.gca.2013.05.016.
Jacques, G., Hoernle, K., Gill, J., Wehrmann, H., Bindeman, I., and Lara, L.E., 2014. Geochemical variations in the Central Southern Volcanic Zone, Chile (38-43 degrees S): The role of fluids in generating arc magmas. Chemical Geology, 371, 27-45, doi: 10.1016/j.chemgeo.2014.01.015.
Kargaranbafghi, F., Neubauer, F., and Genser, J., 2015. Rapid Eocene extension in the Chapedony metamorphic core complex, Central Iran: Constraints from Ar-40/Ar-39 dating. Journal of Asian Earth Sciences, 106, 156-168, doi: 10.1016/j.jseaes.2015.03.010.
Karsli, O., Dokuz, A., Uysal, İ., Aydin, F., Kandemir, R., and Wijbrans, J., 2010. Generation of the Early Cenozoic adakitic volcanism by partial melting of mafic lower crust, Eastern Turkey: implications for crustal thickening to delamination. Lithos, 114, 109-120, doi: 10.1016/j/lithos.2009.08.003.
Kepezhinskas, P., Defant, M.J., and Drummond, M.S., 1996. Progressive enrichment of island arc mantle by melt-peridotite interaction inferred from Kamchatka xenoliths. Geochimica Et Cosmochimica Acta, 60, 1217-1229, doi: 10.1016/0016-7037(96)00001-4.
Kheirkhah, M., Neill, I., Allen, M.B., Emami, M.H., and Ghadimi, A.S., 2020. Distinct sources for high-K and adakitic magmatism in SE Iran. Journal of Asian Earth Sciences, 196, 104355, doi: 10.1016/j.jseaes.2020.104355.
Kimura, J.-I., Hacker, B.R., van Keken, P.E., Kawabata, H., Yoshida, T., and Stern, R.J., 2009. Arc Basalt Simulator version 2, a simulation for slab dehydrationand fluid-fluxed mantle melting for arc basalts: Modeling scheme and application. Geochemistry, Geophysics, Geosystems, 10, n/a-n/a, doi: 10.1029/2008gc002217.
Lechmann, A., Burg, J.P., Ulmer, P., Guillong, M., and Faridi, M., 2018. Metasomatized mantle as the source of Mid-Miocene-Quaternary volcanism in NW-Iranian Azerbaijan: Geochronological and geochemical evidence,Lithos, 304, 311-328, doi: 10.1016/j.lithos.2018.01.030.
Martin, H., 1999. Adakitic magmas: modern analogues of Archaean granitoids. Lithos, 46(3), 411-429, doi: 10.1016/S0024-4937(98)00076-0.
Moazzen, M., Salimi, Z., Rolland, Y., Bröcker, M., and Hajialioghli, R., 2020. Protolith nature and P–T evolution of Variscan metamorphic rocks from the Allahyarlu complex, NW Iran. Geological Magazine, 157(11), 1853-1876, doi: 10.1017/S0016756820000102.
Moghadam, H.S., Griffin, W.L., Kirchenbaur, M., Garbe-Schönberg, D., Zakie Khedr, M., Kimura, J.-I., Stern, R.J., Ghorbani, G., Murphy, R., Y O’Reily, S., Aria, S., and Maghdour-Manshhour, R., 2018a. Roll-Back, Extension and Mantle Upwelling Triggered Eocene Potassic Magmatism in NW Iran. Journal of Petrology, 59, 1417-1465, doi: 10.1093/petrology/egy067.
Moghadam, H.S., Li, Q.L., Griffin, W.L., Stern, R.J., Ishizuka, O., Henry, H., Lucci, F., O'Reilly, S Y., and Ghorbani, G., 2020. Repeated magmatic buildup and deep “hot zones” in continental evolution: The Cadomian crust of Iran: Earth and Planetary Science Letters, 531, doi: 10.1016/j.epsl.2019.115989.
Moghadam, M.C., Tahmasbi, Z., Ahmadi-Khalaji, A., and Santos, J.F., 2018b. Petrogenesis of Rabor-Lalehzar magmatic rocks (SE Iran): Constraints from whole rock chemistry and Sr-Nd isotopes. Chemie Der Erde-Geochemistry, 78, 58-77, doi: 10.1016/j.chemer.2017.11.004.
Mouthereau, F., Lacombe, O., and Verges, J., 2012. Building the Zagros collisional orogen: Timing, strain distribution and the dynamics of Arabia/Eurasia plate convergence. Tectonophysics, 532, 27-60, doi: 10.1016/j.tecto.2012.01.022.
Omrani, J., Agard, P., Whitechurch, H., Benoit, M., Prouteau, G., and Jolivet, L., 2008. Arc-magmatism and subduction history beneath the Zagros Mountains, Iran: A new report of adakites and geodynamic consequences. Lithos, 106, 380-398, doi: 10.1016/j.lithos.2008.09.008.
Pang, K.-N., Chung, S.-L., Zarrinkoub, M.H., Li, X.-H., Lee, H.-Y., Lin, T.-H., and Chiu, H.-Y., 2016. New age and geochemical constraints on the origin of Quaternary adakite-like lavas in the Arabia–Eurasia collision zone. Lithos, 264, 348-359, doi: 10.1016/j.lithos.2016.08.042.
Pearce, J.A., and Peate, D.W., 1995. Tectonic implications of the composition of volcanic arc magmas. Annual Review of Earth and Planetary Sciences, 23, 251-285, doi: 10.1146/annurev.ea.23.050195.001343.
Pearce, J.A., Harris, N.B., and Tindle, A.G., 1984. Trace element discrimination diagrams for the tectonicinterpretation of granitic rocks. Journal of Petrology, 25, 956-983, doi: 10.1093/petrology/25.4.956.
Prelević, D., and Foley, F.S., 2007. Accretion of arc-oceanic lithospheric mantle in the Mediterranean: evidence from extremely high-Mg olivines and Cr-rich spinel inclusions in lamproites. Earth and Planetary Science Letters, 256(1-2), 120-135, doi: 10.1016/j.epsl.2007.01018.
Prelević, D., Jacob, D.E., and Foley, S.F., 2013. Recycling plus: a new recipe for the formation of Alpine–Himalayan orogenic mantle lithosphere. Earth and Planetary Science Letters, 362, 187-197, doi: 10.1016/j.epsl.2012.11.135.
RodrÍguez, C., Sellés, D., Dungan, M., Langmuir, C., and Leeman, W., 2007. Adakitic dacites formed by intracrustal crystal fractionation of water-rich parent magmas at Nevado de Longaví volcano (36· 2 S; Andean Southern Volcanic Zone, Central Chile). Journal of Petrology, 48, 2033-2061, doi: 10.1093/Petrology/egm049.
Saginor, I., Gazel, E., Condie, C., and Carr, M.J., 2013. Evolution of geochemical variations along the Central American volcanic front. Geochemistry Geophysics Geosystems, 14, 4504-4522, doi: 10.1002/ggge.20259.
Salehi Nejad , H., Ahmadipour, H., Moinzadeh, H., Moradian, A., and Santos, J.F., 2020. Geochemistry and petrogenesis of Raviz-Shanabad intrusions (SE UDMB): an evidence for Late Eocene magmatism. International Geology Review, 1-18, doi: 10.1080/00206814.2020.1728585.
Sepidbar, F., Ao, S., Palin, R.M., Li, Q.-L., and Zhang, Z., 2019. Origin, age and petrogenesis of barren (low-grade) granitoids from the Bezenjan-Bardsir magmatic complex, southeast of the Urumieh-Dokhtar magmatic belt, Iran. Ore Geology Reviews, 104, 132-147, doi: 10.1016/j.oregeorev.2018.10.008.
Sun, S.-S., McDonough, W.-s., 1989. Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. Geological society, London, special publications, 42, 313-345, doi: 10.1144/GSL.SP.1989.042.01.19.
Tadayon, M., Rossetti, F., Zattin, M., Nozaem, R., Calzolari, G., Madanipour, S., and Salvini, F., 2017. The Post-Eocene Evolution of the Doruneh Fault Region (Central Iran): The Intraplate Response to the Reorganization of the Arabia-Eurasia Collision Zone. Tectonics, 36, 3038-3064, doi: 10.1002/2017tc004595.
Tang, G.J., Wang, Q., Wyman, D.A., Chung, S.L., Chen, H.Y., and Zhao, Z.H., 2017. Genesis of pristine adakitic magmas by lower crustal melting: A perspective from amphibole composition. Journal of Geophysical Research: Solid Earth, 122, 1934-1948, doi: 10.1002/2016jb013678.
Verdel, C., Wernicke, B.P., Hassanzadeh, J., and Guest, B., 2011. A Paleogene extensional arc flare‐up in Iran. Tectonics, 30(3), doi:10.1029/2010TC002809.
Verdel, C., Wernicke, B.P., Ramezani, J., Hassanzadeh, J., Renne, P.R., and Spell, T.L., 2007. Geology and thermochronology of Tertiary Cordilleran-style metamorphic core complexes in the Saghand region of central Iran. Geological Society of America Bulletin, 119, 961-977, doi: 10.1130/b26102.1.
Winchester, J.A., and Floyd, P.A., 1977. Geochemical discrimination of different magma series and their differentiation products using immobile elements. Chemical Geology, 20, 325-343, doi: 10.1016/0009-2541(77)90057-2.
Workman, R.K., and Hart, S.R., 2005. Major and trace element composition of the depleted MORB mantle (DMM). Earth and Planetary Science Letters, 231, 53-72, doi: 10.1016/j.epsl.2004.12.005.
Xu, W.-C., Zhang, H.-F., Luo, B.-j., Guo, L., and Yang, H., 2015. Adakite-like geochemical signature produced by amphibole-dominated fractionation of arc magmas: An example from the Late Cretaceous magmatism in Gangdese belt, south Tibet. Lithos, 232, 197-210, doi: 10.1016/j.lithos.2015.07.001.
Zhao, Z., Mo, X., Dilek, Y., Niu, Y., DePaolo, D.J., Robinson, P.T., Zhu, D.-C., Sun, C., Dong, G., Zhou, S., Luo, Z., and Hou, Z., 2009. Geochemical and Sr–Nd–Pb–O isotopic compositions of the post-collisional ultrapotassic magmatism in SW Tibet: petrogenesis and implications for India intra-continental subduction beneath southern Tibet. Lithos, 113, 190-212, doi: 10.1016/j.lithos.2009.02.004.
Zhao, Z., Xiong, X., Wang, Q., Wyman, D., Bao, Z., Bai, Z., and Qiao, Y., 2008. Underplating-related adakites in Xinjiang tianshan, China. Lithos, 102, 374-391, doi: 10.1016/j.lithos.2007.06.008
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