Numerical simulation on the special gravity fields and dynamic response in Longmenshan orogenic belt and adjacent area

doi:10.6038/cjg20130111

	Numerical simulation on the special gravity fields and dynamic response in Longmenshan orogenic belt and adjacent area
	Yang Hui 1,2; Teng Ji-Wen 1; Wang Qian-Shen 1; Pi Jiao-Long 1
刊名	CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION
	2013
卷号	56 期号:1 页码:106-116
关键词	Longmenshan orogenic belt Gravity isostasy Earthquake preparation Numerical simulation Rheological model
ISSN号	0001-5733
DOI	10.6038/cjg20130111
文献子类	Article
英文摘要	The Longmenshan orogenic belt is in a very non-isostatic state, which means its crust is in an unstable state. In this paper, 2-D Finite Element Method is used with viscoelastic model to study the geodynamical mechanism of gravitational isostasy through the profile across the Songpan-Garze block, Longmenshan faults and Sichuan basin. The results show that: (1) The motion mode of deep materials is much changed by the isostatic adjustment. The interaction effects of the India plate collision and the gravity potential energy cause the dynamics of the sub-vertical downward asthenospheric flow at the bottom of the Longmen.shan lithosphere, and lead to the exceptionally steep topography at the eastern Tibetan margin as a result of gravitational buoyancy. (2) The distribution of strain-energy, the rheological structure and other results are calculated numerically, which show that the sections with high risk factors coincide with the areas of the Wenchuan earthquake. The different geophysical structures, as well as the different rheological model on both east and west side of Longmenshan faults zone played important roles in the seismogenic mechanism of the Wenchuan earthquake. (3) We suggest that crustal shortening together with isostatic adjustment, including the rapid erosion-related unloading, is a key component of the geodynamic processes on the eastern Tibetan Plateau margin.
WOS关键词	WENCHUAN M(S)8.0 EARTHQUAKE ; WAVE VELOCITY STRUCTURE ; FAULT ZONE ; COLLISION ZONE ; SICHUAN ; CHINA ; MECHANISM ; RUPTURE ; FLOW ; DEFORMATION
WOS研究方向	Geochemistry & Geophysics
语种	英语
出版者	SCIENCE PRESS
WOS记录号	WOS:000314480100011
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/86988]
专题	中国科学院地质与地球物理研究所
通讯作者	Yang Hui
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China 2.Chinese Acad Sci, Inst Geodesy & Geophys, State Key Lab Geodesy & Earths Dynam, Wuhan 430077, Peoples R China
推荐引用方式 GB/T 7714	Yang Hui,Teng Ji-Wen,Wang Qian-Shen,et al. Numerical simulation on the special gravity fields and dynamic response in Longmenshan orogenic belt and adjacent area[J]. CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,2013,56(1):106-116.
APA	Yang Hui,Teng Ji-Wen,Wang Qian-Shen,&Pi Jiao-Long.(2013).Numerical simulation on the special gravity fields and dynamic response in Longmenshan orogenic belt and adjacent area.CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,56(1),106-116.
MLA	Yang Hui,et al."Numerical simulation on the special gravity fields and dynamic response in Longmenshan orogenic belt and adjacent area".CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION 56.1(2013):106-116.