U-Pb Geochronology of Hydrothermal Zircons from the Nyainqentanglha Ductile Shear Zone: Constraints on Inception of Cenozoic East–West Extension in the Tibetan Plateau
U-Pb Geochronology of Hydrothermal Zircons from the Nyainqentanglha Ductile Shear Zone: Constraints on Inception of Cenozoic East–West Extension in the Tibetan Plateau
复制标题
念青唐古拉韧性剪切带热液锆石U-Pb年代学：青藏高原新生代东西伸展起始的制约
DOI：
10.1111/1755-6724.14578
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Wang Chunzeng
中科院分区：
文献类型：
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作者：
Huang Yonggao;Li Yingxu;Han Fei;Jia Xiaochuan;Yang Xuejun;Li Guangming;Kang Zhiqiang;Wang Chunzeng
位于拉萨地体中的念青唐古拉巨型花岗岩基是中新世最年轻的花岗岩侵入体，侵位时间为18.3- 11.0Ma。南北两侧发育一系列北东向左旋正韧性剪切带.韧性剪切带被认为是亚东-古鲁裂谷系的西边界断裂，并有可能为青藏高原大规模的东西向伸展事件提供关键的时间约束。根据念青唐古拉韧性剪切带南部的变形时代，认为该韧性剪切带的东西向伸展不晚于8.6Ma，可能在11 Ma左右，并在8 Ma左右达到最大。首次对念青唐古拉韧性剪切带北方热液锆石进行了高精度年代学分析。这些新资料对青藏高原新生代东西向伸展的起始和构造演化历史提供了令人满意的约束。
The giant Nyainqentanglha granitic batholith, located in the Lhasa Terrane, is the youngest granite pluton emplaced at 18.3–11.0 Ma during the Miocene epoch. A series of NE -striking sinistral normal ductile shear zones developed on its north and south sides. The ductile shear zones are considered to be the western boundary faults of the Yadong-Gulu rift system and have the potential to provide critical temporal constraints for the large-scale East–West extension event in the Tibetan Plateau. Based on deformation ages of the southern Nyainqentanglha ductile shear zone, it was suggested that the E–W extension took place no later than 8.6 Ma, probably at 11 Ma, and reached the peak at around 8 Ma. We have performed a highprecision geochronological analysis of hydrothermal zircons from the northern Nyainqentanglha ductile shear zone collected, to the best of our knowledge, for the first time. The new data provide satisfying constraints on the inception of the EW extension and the tectonic evolutionary history of the Tibetan Plateau during the Cenozoic.