气候变化领域集成服务门户(CCPortal): The influence of topography and crustal heterogeneity on coseismic deformation of the 2008 Mw7.9 Wenchuan Earthquake, China

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DOI	10.1016/j.tecto.2019.228305
	The influence of topography and crustal heterogeneity on coseismic deformation of the 2008 Mw7.9 Wenchuan Earthquake, China
	Zhang C.; Masterlark T.; Tan K.; Wang Q.; Qiao X.; Yang S.
发表日期	2020
ISSN	00401951
卷号	775
英文摘要	The Longmen Shan Thrust Belt, which lies at the convergence of the eastern Tibetan Plateau and Sichuan Basin, is characterized by a topographic relief of 4000 m over a distance of 100 km. While the rock underlying the Sichuan Basin is strong, the crust underlying the Tibetan Plateau is weak. Four models that simulate deformation caused by distributions of dislocations along a geometrically complex fault system are developed to investigate how the contrast in elevational and crustal heterogeneity influences coseismic deformation of the 2008 Mw7.9 Wenchuan earthquake. The models are configured with an assembly precise ramp-décollement structures and planar fault geometries. The coseismic slip distribution is estimated by inverting three component GPS observations with Green's functions calculated for each model configuration. By comparing the slip distribution and residuals among the displacement predictions from these four models and measurements of GPS, the crustal heterogeneity model robustly explained most of the observed GPS horizontal and vertical coseismic displacements. Results revealed four composite dislocation asperities distributed in the shallow crust and a slip of 4–8 m on the sub-surface décollement fault with a depth of ~20 km. The resulting geodetic moment is 8.10 × 1020 Nm, which is in agreement with the seismological estimates. The deep slip predictions obtained with the ramp-décollement fault geometry indicate that the eastern Tibetan Plateau was thrust over the Sichuan Basin rather than the plateau being uplifted owing to the underlying weak crust. © 2019
关键词	Coseismic deformation Crustal heterogeneity Longmenshan thrust belt Topography Wenchuan earthquake
英文关键词	Deformation; Faulting; Geodetic satellites; Topography; Co-seismic displacement; Coseismic deformation; Coseismic slip distribution; Crustal heterogeneity; Displacement prediction; Eastern Tibetan plateau; Thrust belts; Wenchuan Earthquake; Earthquakes; coseismic process; crustal structure; deformation; fault geometry; geodetic network; GPS; Green function; Sichuan earthquake 2008; thrust fault; topography; China; Longmen Mountains
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/207913
作者单位	Key Laboratory of Earthquake Geodesy, Institute of Seismology, China Earthquake Administration, Wuhan, 430071, China; Department of Geology and Geological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, United States; Center of Space Research, China University of Geosciences, Wuhan, 430074, China
推荐引用方式 GB/T 7714	Zhang C.,Masterlark T.,Tan K.,et al. The influence of topography and crustal heterogeneity on coseismic deformation of the 2008 Mw7.9 Wenchuan Earthquake, China[J],2020,775.
APA	Zhang C.,Masterlark T.,Tan K.,Wang Q.,Qiao X.,&Yang S..(2020).The influence of topography and crustal heterogeneity on coseismic deformation of the 2008 Mw7.9 Wenchuan Earthquake, China.Tectonophysics,775.
MLA	Zhang C.,et al."The influence of topography and crustal heterogeneity on coseismic deformation of the 2008 Mw7.9 Wenchuan Earthquake, China".Tectonophysics 775(2020).