Akademik Veri Yönetim Sistemi
GONDWANA RESEARCH, cilt.57, ss.141-156, 2018 (SCI-Expanded, Scopus)
The Sangan Magmatic Complex (SMC), at the northeastern edge of the Lut block, includes a thick pile of extrusive and pyroclastic rocks, intruded by younger granitoid stocks. New zircon U-Pb ages show subaerial eruptions at similar to 42-44 Ma, followed by emplacement of granitoids at similar to 41-40 Ma. The granitoids have high K2O (similar to 3.6-5.9 wt %), with SiO2 (similar to 63.1 and 71.9 wt%) contents. They are metaluminous to peraluminous, talc alkaline and I-type in composition. The SMC magmatic rocks have typical high-K and shoshonitic signatures, and are characterized by enrichment in large-ion lithophile elements (LILEs) and depletion in high-field-strength elements (HFSE). Zircon epsilon(Hf)(t) from the SMC magmatic rocks ranges from +0.45 to +3.5 for volcanic rocks, -1.6 to +2.5 for granitoids and -4.1 to -1.4 for ignimbrites. Zircon delta O-18 values for the SMC are variable from +6.1 to +8.1 parts per thousand, significantly higher than those of mantle-derived melts. The whole-rock epsilon(Nd)(t) values range between -4.5 to -3.5 for granitoids, -4.6 to -3 for volcanic rocks and -5.3 to +0.7 for ignimbrites. The whole-rock Nd and zircon Hf crustal model ages (T-DM(C)) for the SMC magmatic rocks range between 0.8 and 1.2 Ga. All of the SMC magmatic rocks have quite similar trace element patterns, and slightly different whole-rock Nd and zircon Hf isotopic composition. High Pb-207/Pb-204 and Pb-208/Pb-204 values for the SMC rocks indicate the involvement of the thick continental crust during the formation of these rocks. Modeling of zircon O-Hf, bulk-rock trace elements, and Sr-Nd isotopes suggest the magmas were generated by interaction of mantle-derived melts with thick continental crust through AFC processes. Compiled geochronological and geochemical data from east Iranian magmatic belt and Urumieh-Dokhtar magmatic belt allow identification of Eocene-Oligocene flare-up associated with several magmatic pulses. (C) 2018 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.