气候变化领域集成服务门户(CCPortal): Spatial distribution of mid-lower crustal flow in the SE Tibetan Plateau revealed by P-wave velocity and azimuthal anisotropy beneath the Lijiang-Xiaojinhe fault and its vicinity

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DOI	10.1093/gji/ggae080
	Spatial distribution of mid-lower crustal flow in the SE Tibetan Plateau revealed by P-wave velocity and azimuthal anisotropy beneath the Lijiang-Xiaojinhe fault and its vicinity
	Dong, Guiju; Liu, Shaolin; Sun, Kailin; Yang, Dinghui; Li, Mengyang; Wang, Wenshuai; Chang, Kai
发表日期	2024
ISSN	0956-540X
EISSN	1365-246X
起始页码	237
结束页码	2
卷号	237 期号:2
英文摘要	The Lijiang-Xiaojinhe fault (LXF) and its vicinity are located in the transition zone among the Tibetan Plateau (TP), the South China block and the Indochina block. Researchers believe that this area has acted as a key tectonic zone during the evolution of the TP. Owing to the continuous growth and SE-ward expansion of the TP, the LXF and its vicinity have experienced intense deformation. Although different models, such as the rigid block extrusion and mid-lower crustal flow models, have been proposed to explain this intense deformation, a consensus has not yet been achieved. To better understand the deformation of the LXF and its vicinity, a high-resolution image of the subsurface structure must be constructed. In this study, we construct images of P-wave velocity and azimuthal anisotropy structures by using an eikonal equation-based traveltime tomography method. We collect high-quality seismic data from 276 broad-band seismic stations and manually pick a total of 48 037 first arrivals for the tomography study. Our tomographic results reveal a strong low-velocity body below the LXF and its vicinity. In addition, a strong azimuthal anisotropy structure with an N-S-oriented fast velocity direction is distributed along the low-velocity body. These features indicate the occurrence of mid-lower crustal flow, that penetrates across the LXF and extends to the Dianzhong block (DZB). In addition, we find obvious low-velocity perturbations in the mid-lower crust and uppermost mantle beneath the DZB. The low velocities may be attributed to the upwelling of hot materials from the upper mantle. We consider the limited distribution of mid-lower crustal flow on the margin of the SE TP, and mid-lower crustal flow may not play a significant role in the expansion of the TP.
英文关键词	Tomography; Body waves; Crustal imaging; Seismic anisotropy
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:001188324500002
来源期刊	GEOPHYSICAL JOURNAL INTERNATIONAL
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/304697
作者单位	Tsinghua University; Ningxia University
推荐引用方式 GB/T 7714	Dong, Guiju,Liu, Shaolin,Sun, Kailin,et al. Spatial distribution of mid-lower crustal flow in the SE Tibetan Plateau revealed by P-wave velocity and azimuthal anisotropy beneath the Lijiang-Xiaojinhe fault and its vicinity[J],2024,237(2).
APA	Dong, Guiju.,Liu, Shaolin.,Sun, Kailin.,Yang, Dinghui.,Li, Mengyang.,...&Chang, Kai.(2024).Spatial distribution of mid-lower crustal flow in the SE Tibetan Plateau revealed by P-wave velocity and azimuthal anisotropy beneath the Lijiang-Xiaojinhe fault and its vicinity.GEOPHYSICAL JOURNAL INTERNATIONAL,237(2).
MLA	Dong, Guiju,et al."Spatial distribution of mid-lower crustal flow in the SE Tibetan Plateau revealed by P-wave velocity and azimuthal anisotropy beneath the Lijiang-Xiaojinhe fault and its vicinity".GEOPHYSICAL JOURNAL INTERNATIONAL 237.2(2024).