气候变化领域集成服务门户(CCPortal): Three-dimensional seismic velocity structure across the 17 June 2019 Changning M(s)6. 0 earthquake, Sichuan, China

CCPortal

DOI	10.6038/cjg2021O0246
	Three-dimensional seismic velocity structure across the 17 June 2019 Changning M(s)6. 0 earthquake, Sichuan, China
	Sun Quan; Pei ShunPing; Su JinRong; Liu YanBing; Xue XiaoTian; Li JiaWei; Li Lei; Zuo Hong
通讯作者	Pei, SP (通讯作者)
发表日期	2021
ISSN	0001-5733
起始页码	36
结束页码	53
卷号	64 期号:1
英文摘要	The southern Sichuan Basin has a continuously increasing trend in seismic activity since 2015, among which are the numerous moderate and strong events with magnitude larger than 5. 0. The Changning n6. 0 earthquake that occurred on 17 Jun. 2019 is the largest one among these events and is followed by a series of moderate and strong aftershocks. The Changning earthquake sequence is extremely destructive and has led to a heavy loss on local life and property. The studies on the structure features and seismogenic mechanism of this large earthquake can help to understand the reasons why there is unprecedent intense seismic activity in this area, and provide important clues for future work on earthquake prevention and disaster reduction. Based on this point, we collected abundant seismic travel -time data and applied doubledifference tomography method to relocate the Changning earthquake sequence and obtain highresolution 3-D P and S wave velocity as well as Vp/Vs models. The results show that the Changning earthquake sequence is mainly distributed along the core of the Baixiangyan-Shizitan anticline. Significant low velocity and high Vp/Vs features are detected underlying the Changning earthquake source region around the depth of 6 km, suggesting the existence of fluid. Compared to the velocity structure between 7. 5 and 12 km, strong heterogeneity is visible above 6 km in the study region. Besides, the overall anomalous velocity bodies are distributed along the NW-NWW direction above 6 km and NNE or SN direction between 7. 5 and 12 km, suggesting the existence of a detachment layer there. The sedimentary layers are distributed mainly above 6 km, beneath which are the crystalline basement layers. Most seismic events are located above 6 km in depth with small magnitude, suggesting that the seismicity of the study region is mainly dominated by the structure of sedimentary layers. Significant higher velocity anomalies are observed underlying the Changning anticline above 6 km compared with the Baixiangyan-Shizitan and Shuanghe anticlines, which may obstruct the southeastward slip of the seismogenic fault of Changning n6. 0 earthquake, leading to the presence of striking unilateral source rupture.
关键词	TIBETAN PLATEAU WATER INJECTION HAYWARD FAULT SALT MINE BASIN AREA CRUST ANISOTROPY ALGORITHM LOCATION
英文关键词	Changning M(s)6. 0 earthquake; Double-difference tomography; Hypocentral relocation; 3-D seismic velocity structure
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000604835800003
来源期刊	CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION
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/260160
推荐引用方式 GB/T 7714	Sun Quan,Pei ShunPing,Su JinRong,et al. Three-dimensional seismic velocity structure across the 17 June 2019 Changning M(s)6. 0 earthquake, Sichuan, China[J]. 中国科学院青藏高原研究所,2021,64(1).
APA	Sun Quan.,Pei ShunPing.,Su JinRong.,Liu YanBing.,Xue XiaoTian.,...&Zuo Hong.(2021).Three-dimensional seismic velocity structure across the 17 June 2019 Changning M(s)6. 0 earthquake, Sichuan, China.CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,64(1).
MLA	Sun Quan,et al."Three-dimensional seismic velocity structure across the 17 June 2019 Changning M(s)6. 0 earthquake, Sichuan, China".CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION 64.1(2021).