Precise Dating and Geological Significance of the Caledonian Shangyou Pluton in South Jiangxi Province

作     者：MAO Jianren ZENG Qingtao LI Zilong HU Qing ZHAO Xilin YE Haimin 

作者机构：Nanjing Institute of Geology and Mineral Resources Jiangsu Province Nanjing Jiangsu 210016 Earth Science College Jilin University Changchun Jilin 130061 Geoscience Department Zhejiang University Hangzhou Zhejiang 310027 

出 版 物：《Acta Geologica Sinica(English Edition)》 (地质学报（英文版）)

年 卷 期：2008年第82卷第2期

页      面：399-408页

核心收录：

学科分类：0709[理学-地质学] 070901[理学-矿物学、岩石学、矿床学] 07[理学] 0708[理学-地球物理学] 

基　　金：The Foundation Geology Research Projects supervised by the Department of Science and Technology and International Cooperation, and Chinese Geological Survey(200313000070 1212010611805) 

主　　题：granite precise dating geological significance Caledonian South Jiangxi Province 

摘      要：The zircon SHRIMP dating age for the Shangyou granites is 464±11 Ma. The geological feature of the pluton is consistent with the isotopic age, which shows that it is a product of Caledonian orogenesis. The Shangyou granites are regarded as peraluminous crust-derived granites to possess the typical geochemical characteristics of calc-alkaline rocks on the active continental margin with enriched Si, K, Al （A/CNK -- 1.11 on average）, HREE, Rb, U, Th and heavily depleted V, Cr, Co, Ni, as well as Ti-Y, Nb-Ta, Zr, Sr, P and Ba, to be commonly corundum normative （av C -- 1.44）. The Shangyou granites with higher 87Sr/86Sr ratios （0.707126-0.712186）, ENd（t） values （-7.29 to -10.22） and （tDM） values （1.52-1.63 Ga）, which are considered to result from partial melting of continental crust metamorphic sedimentary rocks with relatively low of crust maturation degree corresponding to the Middle Proterozoic, to have some possible contributions of mantle-derived components. The Shangyou granites are regarded as post-collision granites, which were formed in a transitional tectonic setting from compression to extension in the Middle Ordovician period after the Yangtze plate was subducted beneath the Cathaysian plate. The Ar-Ar total ages of K-feldspar and biotite are 292.1 Ma and 295.5 Ma respectively, which have recorded information of a late-stage thermal alteration event.