Geochronology, geochemistry, and Sr-Nd isotopes of Early Carboniferous magmatism in southern West Junggar, northwestern China: Implications for Junggar oceanic plate subduction

作     者：LIU Pengde LIU Xijun XIAO Wenjiao ZHANG Zhiguo SONG Yujia XIAO Yao LIU Lei HU Rongguo WANG Baohua LIU Pengde;LIU Xijun;XIAO Wenjiao;ZHANG Zhiguo;SONG Yujia;XIAO Yao;LIU Lei;HU Rongguo;WANG Baohua

作者机构：Guangxi Key Laboratory of Hidden Metallic Ore Deposits ExplorationCollege of Earth SciencesGuilin University of TechnologyGuilin 541004China Xinjiang Research Center for Mineral ResourcesXinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of ResourceGuilin University of TechnologyGuilin 541004China 

出 版 物：《Journal of Arid Land》 (干旱区科学（英文版）)

年 卷 期：2021年第13卷第11期

页      面：1163-1182页

核心收录：

学科分类：0709[理学-地质学] 081803[工学-地质工程] 08[工学] 0708[理学-地球物理学] 0818[工学-地质资源与地质工程] 0705[理学-地理学] 0815[工学-水利工程] 

基　　金：This study was jointly supported by the CAS"Light of West China"Program(2018-XBYJRC-003) the National Natural Science Foundation of China(41772059,92055208) the Guangxi Natural Science Foundation for Distinguished Young Scholars,China(2018GXNSFFA281009) the Fifth Bagui Scholar Innovation Project of Guangxi Zhuang Autonomous Region,China.We are grateful for editor's excellent editorial handling and constructive comments from two anonymous reviewers,which substantially improved the final presentation of the manuscript.This is a contribution to International Geoscience Programme(IGCP)662 and Guangxi Key Mineral Resources Deep Exploration Talent Highland 

主　　题：Early Carboniferous magmatism geochronology geochemistry Junggar Oceanic plate subdution West Junggar Central Asian Orogenic Belt 

摘      要：West Junggar is a key area for understanding intra-oceanic plate subduction and the final closure of the Junggar *** of the Carboniferous tectonic evolution of the Junggar Ocean region is required for understanding the tectonic framework and accretionary processes in West Junggar,Central Asian Orogenic Belt.A series of Early Carboniferous volcanic and intrusive rocks,namely,basaltic andesite,andesite,dacite,and diorite,occur in the Mayile area of southern West Junggar,northwestern *** new LA-ICPMS zircon U-Pb geochronological data reveal that diorite intruded at 334(±1)Ma,and that basaltic andesite was erupted at 334(±4)*** intrusive and volcanic rocks are calc-alkaline,display moderate MgO(1.62%-4.18%)contents and Mg#values(40-59),and low Cr(14.5×10-6-47.2×10-6)and Ni(7.5×10-6-34.6×10-6)contents,and are characterized by enrichment in light rare-earth elements and large-ion lithophile elements and depletion in heavy rare-earth elements and high-field-strength elements,meaning that they belong to typical subduction-zone island-arc *** samples show low initial 87Sr/86Sr ratios(range of 0.703649-0.705008),positiveεNd(t)values(range of 4.8-6.2 and mean of 5.4),and young TDM Nd model ages ranging from 1016 to 616 Ma,indicating a magmatic origin from depleted mantle involving partial melting of 10%-25%garnet and spinel *** our results with those of previous studies,we suggest that these rocks were formed as a result of northwestward subduction of the Junggar oceanic plate,which caused partial melting of sub-arc *** conclude that intra-oceanic arc magmatism was extensive in West Junggar during the Early Carboniferous.