Geochronology,Geochemistry,and Implications of Aplite Dyke in the Giant Jiama Porphyry Copper System,Tibet

作     者：QI Jing TANG Juxing LIN Bin YANG Hairui TANG Xiaoqian TANG Pan FANG Xiang ZHANG Tingting LI Faqiao SUN Miao WANG Mengdie CUI Hao XIE Jinling QI Jing;TANG Juxing;LIN Bin;YANG Hairui;TANG Xiaoqian;TANG Pan;FANG Xiang;ZHANG Tingting;LI Faqiao;SUN Miao;WANG Mengdie;CUI Hao;XIE Jinling

作者机构：School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China MNR Key Laboratory of Metallogeny and Mineral AssessmentInstitute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Institute of Mineral ResearchChina Metallurgical Geology BureauBeijing 101300China China Mining Federation of Beijing Consulting CenterBeijing 100044China Southwest University of Science and TechnologyMianyangSichuan 621000China Chinese Academy of Geological SciencesBeijing 100037China Development and Research CenterChina Geological SurveyBeijing 100037China Chengdu University of TechnologyChengdu 100059China Tibet UniversityLhasa 850000China 

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

年 卷 期：2023年第97卷第5期

页      面：1406-1421页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：supported by the National Key Research and Development Program of China(Grant No.2022YFC2905001) National Natural Science Foundation of China(Grant Nos.42272093 and 42230813) Basic Research Fund of Chinese Academy of Geological Sciences(Grant Nos.JKYZD202316,KJ2102,KK2116,and JKY202208) Geological Survey Project(Grant No.DD20221684) China Scholarship Council(Grant No.CSC202206400059) 

主　　题：U-Pb age Sr-Nd-Pb isotope geochemistry aplite dyke Jiama 

摘      要：Jiama is a giant,high-grade porphyry copper system in the Gangdese metallogenic belt,*** intermediate-felsic porphyries intruded in this deposit,some of which are strongly associated with copper-polymetallic *** ore-bearing porphyries include monzogranite,granodiorite,and quartz diorite porphyries.A new granite aplite dyke was found in the south of *** age,genesis,and relationship with ore-related magmatism are ***,its emplacement age and petrogenesis were determined using mineralogy,zircon U-Pb dating,geochemistry,and Sr-Nd-Pb isotope *** zircon LA-ICP-MS U-Pb age of the aplite dyke is 16.66±0.21 Ma(n=14,MSWD=0.66),earlier than that of the ore-bearing porphyries(~15 Ma)in ***,the aplite exhibits high amounts of silicon(SiO_(2)=73.39%-74.74%),potassium(K_(2)O=5.12%-6.61%),aluminum(Al_(2)O_(3)=14.25%-14.69%),and light/heavy rare earth elements(LREE/HREE=12.12-16.19)as well as negative europium(δEu=0.47-0.72)and weak negative cerium anomalies(δCe=0.84-0.93).The aplite dyke is characteristic of metaluminous-peraluminous I-type granite,which is rich in large-ion lithophile elements(Rb,Ba,Th and U)and depleted in high-field-strength elements(Nb,P and Ti).The aplite dyke and ore-bearing porphyries in the Jiama deposit are the results of a partial melting of the juvenile lower crust,according to whole-rock geochemistry and Sr-Nd-Pb isotope data,but the dyke and ore-bearing porphyries were emplaced from the same magma chamber at different ***,the aplite dyke shows the composition of the early evolution stage of shallow magma in the Jiama deposit and is the product of rapid condensation and crystallization.