Numerical Simulation of Equivalent Stress Field after the Impoundment of the Three Gorges Reservoir and the Seismogenic Mechanism of Hujiaping MS4.1 Earthquake
详细信息
- 责任者：Wu Jianchao (Institute of Seismology ; CEA ; Wuhan 430071 ; China) ; Chen Shujun
- 刊名：Journal of Seismological Research
- 出版年：2012
- 卷期：35(1)
- 关键词：孕震构造 ; seismogenic tectonics ; 应力场 ; stress fields ; 长江三峡 ; Yangtze Three Gorgees
- 页码：p.42-47
- 图表：6 illus., 1 table, 15 refs.
- 分类号：0500
- 出版序号：20130088
- issnNo：ISSN1000-0666
- isbnNo：CN53-1062/P
摘要
Using finite element method,we established a 3D linear elastic finite element model of the head area of the Three Gorges reservoir after the Hujiaping MS4.1 earthquake occurred after the 172 m level experimental impoundment. Then, the authors calculated and obtained the equivalent stress field under 172 m water level and that in 8 km depth in the head area of the Three Gorges before impoundment, which are consistent with the distribution characteristics of contemporaneous flowing gravity field abnormality in this area. On this basis, the authors compared the equivalent stress field changes after the impoundment with the Hujiaping MS4.1 earthquake, and found that this earthquake occurred in the gradient zone between the increasing zone and decreasing zone of the equivalent stress. The authors analyzed that the equivalent stress varied distinctly in the gradient zone, where the stress and strain was accumulated and tectonic activity was intense.