Early Cretaceous to Middle Eocene Magmatic Evolution of Eastern Pontides:Zircon U-Pb Ages and Hf Isotopes,and Geochemical and Sr-Nd Isotopic Constraints from Multiphase Granitoids,NE Turkey

作     者：Abdullah Sar Sevcan Kurum Ahmet Feyzi Bingol Abdullah Sar;Sevcan Kürüm;Ahmet Feyzi Bing?l

作者机构：Department of Geological EngineeringFirat UniversityElazig 23119Turkey 

出 版 物：《Journal of Earth Science》 (地球科学学刊（英文版）)

年 卷 期：2023年第34卷第2期

页      面：518-535页

核心收录：

学科分类：070902[理学-地球化学] 070903[理学-古生物学与地层学(含：古人类学)] 0709[理学-地质学] 07[理学] 070901[理学-矿物学、岩石学、矿床学] 0708[理学-地球物理学] 

基　　金：supported by the Scientific and Technical Research Council of Turkey International Research Fellowship Programme(Nos.TüB?TAK 2214-A,1059B141800146) supported by OYP research foundation。 

主　　题：zircon U-Pb ages Hf isotope Sr-Nd isotope Cretaceous to Eocene Magmatism Eastern Pontides geochemistry 

摘      要：The Eastern Pontides orogenic belt(EPOB)represents a significant segment of the AlpineHimalayan orogenic belt that evolved from the Paleozoic to Cenozoic periods.Here we report new zircon U-Pb ages,together with Lu-Hf isotopes,and whole-rock geochemical and Sr-Nd isotopic analyses of plutonic rocks from EPOB,northeastern Turkey.Our aim is to interpret magmatic evolution in which the granitoids formed.Zircon U-Pb dating of six samples yielded crystallization ages of~134,~82,~39 Ma,respectively.They show a wide range of87Sr/86Sr((i))(0.7039–0.7109),andεNd(t)values varying from-9 to+4.6,yielding model ages(TDM)from 520 to 1623 Ma,suggesting a heterogeneous magma source.Dated zircons show exlusively positiveεHf(t)values(+12.4 to+1.4),yielding model ages(TDM)from 352 to 1059 Ma,implying that they are most likely derived from a juvenile lower crust rather than the mature continental crust.In this study,we suggested that the northward subduction of the Neo-Tethyan oceanic slab began from the Early Cretaceous and resulted in the Late Cretaceous magmatism.Moreover,the Middle Eocene magmatism in the EPOB was related to the collision of the Anatolide Taurid Platform(ATP)with the Pontides.