Geochronology and Geochemistry of Wangjiadashan Quartz Syenite Porphyry in Suizao Area of Hubei Province in the Tongbai-Dabie Orogenic Belt  

作　　者：Pan-Pan Niu Shao-Yong Jiang 

机构地区：[1]State Key Laboratory of Geological Processes and Mineral Resources,School of Earth Resources,China University of Geosciences,Wuhan 430074,China [2]Key Laboratory of Geological Survey and Evaluation of Ministry of Education,China University of Geosciences,Wuhan 430074,China [3]Collaborative Innovation Center for Exploration of Strategic Mineral Resources,China University of Geosciences,Wuhan 430074,China

出　　处：《Journal of Earth Science》2023年第3期790-805,共16页地球科学学刊（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.42030811);the National Key R&D Program of China(No.2017YFC0601404);the special fund from the State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences(No.MSFGPMR03-2);the Hubei Geological Bureau(No.KJ2016-5)。

摘　　要：The Wangjiadashan area in Suizhou-Zaoyang region of Hubei Province in the Tongbai-Dabie orogenic belt hosts important copper-gold deposits and contains a large number of quartz syenite porphyry dykes,occurring mostly along the NEE-trend faults.In this study,we used LA-ICP-MS zircon U-Pb dating method and obtained an age of 143.6±1.4 Ma,which represents the emplacement of these quartz syenite porphyry dykes was at the Yanshanian,but it was slightly earlier than the previously reported ages(139-135 Ma)for granites widespreading in Suizao area.The geochemical data of the Wangjiadashan quartz syenite porphyry show high K_(2)O,CaO,Na_(2)O and Al_(2)O_(3)contents but extremely low MgO contents(0.01 wt.%-0.46 wt.%).The geochemical characteristics indicate that these quartz syenite porphyry dykes belong to the typical C-type adakite and were possibly formed in the post-collisional environment.Multi-isotopic(Sr-Nd-Pb-Hf)analyses indicate that these quartz syenite porphyry dykes were originated from crust without distinct mantle materials involved.It is suggested that the Wangjiadashan quartz syenite porphyry was generated from partial melting of the thickened lower continental crust,and garnet but no plagioclase was left as residual phase.Compared with the widespread granites of the Tongbai area,the Wangjiadashan quartz syenite porphyry formed earlier and derived from more juvenile and K-rich lower crust,while they all belong to intensive magmatism concentrated during the Early Cretaceous epoch in the Tongbai area.

关 键 词：quartz syenite porphyry zircon U-Pb dating GEOCHEMISTRY Sr-Nd-Pb-Hf isotopes PETROGENESIS Wangjiadashan Tongbai Orogen 

分 类 号：P542.2[天文地球—构造地质学] P618.41[天文地球—地质学] P618.5