Geochronology and Geochemistry of the Early Paleozoic Ore-host Volcanic Sequence in the Kalatag Area,East Tianshan,NW China:Implications for the Tectonic Evolution  

作　　者：ZHANG Zhenlong YANG Fuquan ZHOU Taofa GENG Xinxia ZHANG Zhixin YANG Chengdong QIU Zhanlin 

机构地区：[1]School of Resource Engineering,Longyan University,Longyan,Fujian 364012,China [2]MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China [3]School of Resources and Environmental Engineering,Hefei University of Technology,Hefei 230009,China [4]The National 305 Project Office of Xinjiang,Urumuqi 830000,China [5]Xinjiang Research Center for Mineral Resources,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China

出　　处：《Acta Geologica Sinica(English Edition)》2023年第5期1372-1387,共16页地质学报（英文版）

基　　金：supported by the National Key R&D Program of China(Grant No.2022YFC2903305);the National Natural Science Foundation of China Program(Grant No.42072100);Xinjiang Uygur Autonomous Region'Tianchi Talents'Introduction Program。

摘　　要：The East Tianshan contains many late Paleozoic magmatic and polymetallic deposits.Recent studies demonstrate that the early Paleozoic volcanic rocks discovered in the northern region of East Tianshan can be subdivided into the Daliugou,Hongliuxia and Kalatag formations.Here,we report zircon U-Pb ages of volcanic rocks and quartz diorite porphyry,together with whole-rock geochemical and Sr-Nd isotope data of early Paleozoic volcanic rocks,in order to investigate their petrogenesis and geodynamic setting.Zircon U-Pb analyses of the rocks suggest that the Kalatag Formation formed at ca.438-413 Ma.Geochemical characteristics of the early Paleozoic volcanic rocks exhibit typical subduction-related features.They have high Mg^(#)(44-75),positiveε_(Nd)(t)values(0.25-7.88),low^(87)Sr/^(86)Sr ratios(0.70457 to 0.70588)and young two-stage Hf isotope model ages(551-446 Ma),consistent with a depleted mantle origin with limited crustal contamination.The basaltic andesite and andesite have relatively high MgO contents(6.1-9.4 wt%),suggesting that they belong to high-magnesian andesites.They were most likely derived from the partial melting of mantle peridotite caused by the addition of fluids released by subducted oceanic slab.Based on regional geology,geochemical characteristics and previous studies,we infer that the southward subduction of the Junggar Ocean slab resulted in the generation of early Paleozoic volcanic rocks and arc setting-related metallogenic systems in the Kalatag area.

关 键 词：geodynamic setting VMS deposit petrogeochemistry Kalatag area East Tianshan 

分 类 号：P611[天文地球—矿床学] P588.14[天文地球—地质学]