Multi-stage metallogeny in the southwestern part of South China,and paleotectonic and climatic implications:A high precision geochronologic study  

作　　者：Yanbin Liu Lifei Zhang MSantosh Guochen Dong Hongying Zhou Chaoyang Que Cheng-Xue Yang 

机构地区：[1]State Key Laboratory of Geological Processes and Mineral Resources,and School of Earth Science and Resources,China University of Geosciences,Beijing 100083,China [2]MOE Key Laboratory of Orogenic Belts and Crustal Evolution,School of Earth and Space Sciences,Peking University,Beijing 100871,China [3]Department of Earth Science,University of Adelaide,Adelaide SA 5005,Australia [4]Tianjin Institute of Geology and Mineral Resources,China Geological Survey,Tianjin 300170,China [5]Zijin Mining Industry Groups Co.,Ltd.,Xiamen 361009,Fujian,China

出　　处：《Geoscience Frontiers》2023年第3期131-147,共17页地学前缘（英文版）

基　　金：supported by the China Geological Survey Program(Grant Nos.1212011121260,1212011220928);the National Natural Science Foundation of China(Gant No.91755206)。

摘　　要：The South China Block(SCB)is among the large-scale W-Sn mineralized regions of the globe.The Laojunshan W-Sn-dominant ore area(LOA)in the western part of the SCB preserves the records of the tectonic history of the Tethys realm extending through North Vietnam,and Yangtze to Cathaysia blocks,with coeval formation of giant metallic deposits.The prolonged tectonic activities and their control on the genesis and spatio-temporal distribution of giant metallic deposits in the LOA provide a window for a holistic understanding of the tectono-metallogenesis of the SCB.In this study,we present results from a multi-chronologic study to determine the timing of formation of the cassiterite-wolframite-schee lite mineralization.The results suggest three distinct tectono-metallogenic periods in the LOA during the geodynamic evolution of the surrounding tectonic units.The opening of the Proto-Tethys Ocean between the Yangtze-Indochina blocks and the westward Paleo-Pacific subduction beneath the Cathaysia block(420–380 Ma)jointly contributed to the Silurian to early Devonian intracontinental orogeny in the middle of the SCB that involved top-to-the-north thrusting along NE-striking shear zones.This event generated the Dulong-Song Chay granitoids,together with the formation of Xinzhai Sn deposit related to sheared mylonitic granites(ca.419 Ma)and pegmatites(ca.389 Ma),which include the early-stage Sn-sulfide skarn(ca.418 Ma)and the late-stage Sn-bearing schist(ca.389 Ma).During the Late Permian to Late Triassic(260–220 Ma),with the closure of the Proto-Tethys oceans in the west and ongoing Paleo-Pacific westward subduction in the east,the SCB and Indochina Block(IB)were amalgamated which also marks the time of formation of the Nanwenhe scheelite skarn deposit.The subducted PaleoTethys oceanic crust was likely entrained by the nearby rising Emeishan mantle plume(270–259 Ma),which formed the Maguan diabase(ca.260 Ma)that shows significantly older Re-Os model age of ca.268 Ma,suggesting that the Nanwenhe mineralization is potent

关 键 词：Sn-W mineralization GEOCHRONOLOGY Tectonics setting South China Block Tethys realm 

分 类 号：P618.2[天文地球—矿床学] P597[天文地球—地质学]