Paleozoic convergence processes in the southwestern Central Asian Orogenic Belt:Insights from U–Pb dating of detrital zircons from West Junggar,northwestern China  

作　　者：Pan Zhang Guocan Wang Tianyi Shen Ali Polat Chengyu Zhu 

机构地区：[1]Center for Global Tectonics,School of Earth Sciences,China University of Geosciences,Wuhan 430074,China [2]Institute of Geological Survey,China University of Geosciences,Wuhan 430074,China [3]School of the Environmental Sciences,University of Windsor,Windsor,ON N9B 3P4,Canada [4]State Key Laboratory of Geological Processes and Mineral Resources(GPMR),China University of Geosciences,Wuhan 430074,China

出　　处：《Geoscience Frontiers》2021年第2期531-548,共18页地学前缘（英文版）

基　　金：This study was financially supported by the China Geological Survey(Grant Nos.1212011120502,1212011220245,DD20179607,DD20160060);This research was also supported by an Opening fund of GRMR201607 from the State Key Lab of GPMR to A.Polat;A.Polat also acknowledges the support by NSERC(Canada)and China University of Geosciences at Wuhan.

摘　　要：The West Junggar orogen,located in the southwestern Central Asian Orogenic Belt(CAOB),preserves an abundant record of tectonic processes associated with the evolution of the Junggar Ocean.In this study,we use detrital zircon U–Pb age data from Ordovician to Carboniferous sandstones in the southern and central West Junggar domains,complemented by literature data,to better constrain the tectonic evolution of the southwestern CAOB.The Kekeshayi,Qiargaye,and Laba formations in the southern West Junggar domain were deposited during the Darriwilian-Sandbian,Katian-Aeronian,and Homerian-Emsian,respectively.Detrital zircon provenances of these formations display a marked shift from the southern West Junggar domain to the Paleo-Kazakhstan Continent(PKC).This suggests that the southern West Junggar intra-oceanic arc might have gradually accreted to the northern margin of the PKC prior to the Emsian,which has significantly contributed to the lateral growth of the PKC.The Carboniferous strata,Xibeikulasi,Baogutu,and Tailegula formations,in the central West Junggar domain represent a coherent sequence of volcaniclastic turbidites and were deposited in a progressively shrinking remnant oceanic basin during the Visean to Moscovian.They contain unimodal detrital zircon distributions and are derived from the local and coeval magmatic rocks in the central West Junggar domain.We propose that the final closure of the Junggar Ocean likely occurred in the end of the Late Carboniferous in response to regional amalgamation events in the southwestern CAOB,which marks the final assembly of the Kazakhstan Orocline.The central and southern West Junggar domains underwent individual evolution in the Paleozoic,and were recombined by the significant intra-continental reworking along the large-scale strike-slip faults.

关 键 词：CAOB West Junggar Detrital zircon Sedimentary provenances Paleozoic evolution 

分 类 号：P542.2[天文地球—构造地质学]