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DOI	10.1016/j.jseaes.2023.105633
	Pn velocity and anisotropy at the lithospheric mantle wedge beneath the middle-eastern Gangdese Metallogenic Belt, southern Tibet, China
	Li, Yulan; He, Rizheng; Wang, Baoshan; Niu, Xiao; Li, Zongxu
发表日期	2023
ISSN	1367-9120
EISSN	1878-5786
卷号	258
英文摘要	The lithospheric mantle wedge beneath the middle-eastern Gangdese Metallogenic Belt (GMB), located at the forefront of the India-Eurasia collision-subduction zone retains many traces of structure evolution, which can be revealed by the velocity and anisotropy structure of the uppermost mantle of this region. In this study, high-resolution structures of the Pn velocity and anisotropy beneath the middle-eastern GMB are presented using interstation Pn differential travel-time data recorded by a dense broadband seismic array. The average Pn-wave velocity of 8.13 km/s beneath the GMB is close to that of the peridotite. The Pn velocity and anisotropy show prominent differences across the Jiali dextral strike-slip fault (JLF, similar to 31 degrees N) on the east of Shenza-Xietongmen rift, as indicates that the JLF (31 degrees N) is an uppermost mantle trace of the Shiquan River-Nam Tso Melange Zone. Low Pn velocity (<8.0 km/s) and a nearly EW-oriented Pn fast-wave direction to the north of the JLF, suggesting the EW extension of the Eurasian plate. NE-oriented Pn fast-wave direction with strange intensity (>0.03) to the south of the JLF indicates the direct influence of the Indian plate northward subduction. The rifts located at the boundary of high and low-velocity anomalies imply that the rift system formed under the influence of lithospheric mantle activity. Based on the NE compression caused by the Indian plate's northeastward subduction, some of the forced upwellings of thermal material generated within the mantle wedge tip caused an EW extension of the crust. Subsequently, the rifts system was locally formed.
关键词	Middle-eastern Gangdese Metallogenic Belt Pn velocity and anisotropy Jiali dextral strike-slip fault the trace of SNMZ Rift formation mechanism
英文关键词	LHASA TERRANE; SEISMIC ANISOTROPY; SUBDUCTION BENEATH; N-S; PLATEAU; EXTENSION; EVOLUTION; SLAB; PETROGENESIS; DEFORMATION
WOS研究方向	Geosciences, Multidisciplinary
WOS记录号	WOS:001123981100001
来源期刊	JOURNAL OF ASIAN EARTH SCIENCES
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283502
作者单位	Chinese Academy of Sciences; University of Science & Technology of China, CAS; China Geological Survey; Chinese Academy of Geological Sciences
推荐引用方式 GB/T 7714	Li, Yulan,He, Rizheng,Wang, Baoshan,et al. Pn velocity and anisotropy at the lithospheric mantle wedge beneath the middle-eastern Gangdese Metallogenic Belt, southern Tibet, China[J],2023,258.
APA	Li, Yulan,He, Rizheng,Wang, Baoshan,Niu, Xiao,&Li, Zongxu.(2023).Pn velocity and anisotropy at the lithospheric mantle wedge beneath the middle-eastern Gangdese Metallogenic Belt, southern Tibet, China.JOURNAL OF ASIAN EARTH SCIENCES,258.
MLA	Li, Yulan,et al."Pn velocity and anisotropy at the lithospheric mantle wedge beneath the middle-eastern Gangdese Metallogenic Belt, southern Tibet, China".JOURNAL OF ASIAN EARTH SCIENCES 258(2023).