气候变化领域集成服务门户(CCPortal): Seismic Evidence for Lateral Asthenospheric Flow Beneath the Northeastern Tibetan Plateau Derived From S Receiver Functions

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DOI	10.1029/2018GC007986
	Seismic Evidence for Lateral Asthenospheric Flow Beneath the Northeastern Tibetan Plateau Derived From S Receiver Functions
	Xu, Qiang; Pei, Shunping; Yuan, Xiaohui; Zhao, Junmeng; Liu, Hongbing; Tu, Hongwei; Chen, Shuze
通讯作者	Xu, Q (通讯作者)
发表日期	2019
EISSN	1525-2027
起始页码	883
结束页码	894
卷号	20 期号:2
英文摘要	We present detailed lithospheric images of the NE Tibetan Plateau by applying the depth migration technique to S receiver functions derived from 113 broadband stations. Our migrated images indicate that the lithosphere-asthenosphere boundary (LAB) lies at depths of 105-120km beneath the Qilian terrane and reaches depths of 126-140km below the Alxa and Ordos blocks. The most prominent variation in the LAB depth is the presence of LAB steps of no less than 20km in the transition zone between the active NE Tibetan Plateau and the surrounding cratonic Alxa and Ordos blocks, which conflicts with the model of southward subduction of the Alxa and Ordos blocks. Furthermore, the marked LAB steps occur at 13010km away from the southern surficial boundary faults between the NE Tibetan Plateau and the surrounding tectonic provinces, corresponding to the North Qilian fault and the Liupanshan fault, respectively. Therefore, we propose that these scenarios of LAB can be attributed to the delamination of fragmented mantle lithosphere in the transition zone between the NE Tibetan Plateau and the surrounding Alxa and Ordos blocks, triggered by lateral asthenospheric flow. In addition, our observations of a thin lithosphere with thickness of 107-115km beneath the Songpan-Ganzi terrane and the west Qinlin orogen greatly facilitate the process of underlying lateral asthenospheric flow. The isostatic uplift of the plateau caused by the delamination of fragmented mantle lithosphere, together with increased horizontal compressive stress, may have led to the outward growth of the NE Tibetan Plateau.
关键词	MANTLE STRUCTURE BENEATH ASIAN LITHOSPHERE QILIAN SHAN CRUSTAL MARGIN DEFORMATION ANISOTROPY DISCONTINUITY SUBDUCTION DYNAMICS
英文关键词	S receiver functions; depth migration technique; LAB; northeastern Tibetan Plateau; asthenospheric flow
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000461745200018
来源期刊	GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/259509
推荐引用方式 GB/T 7714	Xu, Qiang,Pei, Shunping,Yuan, Xiaohui,et al. Seismic Evidence for Lateral Asthenospheric Flow Beneath the Northeastern Tibetan Plateau Derived From S Receiver Functions[J]. 中国科学院青藏高原研究所,2019,20(2).
APA	Xu, Qiang.,Pei, Shunping.,Yuan, Xiaohui.,Zhao, Junmeng.,Liu, Hongbing.,...&Chen, Shuze.(2019).Seismic Evidence for Lateral Asthenospheric Flow Beneath the Northeastern Tibetan Plateau Derived From S Receiver Functions.GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS,20(2).
MLA	Xu, Qiang,et al."Seismic Evidence for Lateral Asthenospheric Flow Beneath the Northeastern Tibetan Plateau Derived From S Receiver Functions".GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS 20.2(2019).