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    中国百强科技报刊

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    Volume 43 Issue 12
    Dec.  2018
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    Article Contents
    Bai Jianke, Chen Junlu, Zhu Xiaohui, Feng Bo, 2018. Provenance Characteristics of Kalamaili Formation in Northeastern Margin of Junggar Basin: Constraints of Geochemistry and Detrital Zircon U-Pb Geochronology. Earth Science, 43(12): 4411-4426. doi: 10.3799/dqkx.2018.587
    Citation: Bai Jianke, Chen Junlu, Zhu Xiaohui, Feng Bo, 2018. Provenance Characteristics of Kalamaili Formation in Northeastern Margin of Junggar Basin: Constraints of Geochemistry and Detrital Zircon U-Pb Geochronology. Earth Science, 43(12): 4411-4426. doi: 10.3799/dqkx.2018.587

    Provenance Characteristics of Kalamaili Formation in Northeastern Margin of Junggar Basin: Constraints of Geochemistry and Detrital Zircon U-Pb Geochronology

    doi: 10.3799/dqkx.2018.587
    • Received Date: 2018-03-10
    • Publish Date: 2018-12-15
    • The Devonian Kalamaili Formation is widely exposed in the northeastern margin of Junggar basin, while its depositional age and tectonic setting are still in debate. In this study, an integrated analysis of petrology, geochemistry and isotope chronology for the Kalamaili Formation was carried out. The results show that the Kalamaili Formation, characterized by turbidite features, was mainly deposited in the slope and semi-deep ocean. Geochemically, the Kalamaili Formation sandstone is characterized by high SiO2, low Al2O3/SiO2 and high K2O/Na2O. The REE distributing patterns show rightward incline and weaker negative Eu anomaly (ΣLREE/ΣHREE=4.81-8.03, δEu=0.59-0.80). Tectonic-setting discrimination diagrams of the Kalamaili Formation sandstone indicate a passive-margin tectonic setting. The detrital zircon age spectrum of the Kalamaili Formation sandstone was composed of two age groups, including 393-524 Ma and 823-3 077 Ma, which correspond to the Early Paleozoic orogenic belt and Precambrian crystalline basement of Junggar basin, respectively. It is concluded that the Kalamaili Formation was deposited in a passive-margin of the northeastern Junggar block during the Early-Middle Devonian.Since the Middle Devonian, the Paleozoic Kalamaili Ocean subducted northward continuously, and then formed the Yemaquan island arc and related forearc sedimentary system, and finally the Kalamaili Ocean closed prior to the Early Carboniferous.

       

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