Analysis of Characteristics of Geological Hazards by “4·20” Lushan Earthquake in Sichuan, China
详细信息
- 责任者：Pei Xiangjun (State Key Laboratory of Geohazard Prevention and Geoenvironment Protection ; Chengdu University of Technology ; Chengdu 610059 ; China) ; Huang Runqiu
- 刊名：Journal of Chengdu University of Technology
- 出版年：2013
- 卷期：40(3)
- 关键词：地震 ; earthquakes ; 次生灾害 ; derived disasters ; 四川 ; Sichuan Province
- 页码：p.257-263
- 图表：illus., 1 table, 11 refs.
- 分类号：1800
- issnNo：ISSN1671-9727
- isbnNo：CN51-1634/N
摘要
The "4·20" Lushan earthquake is another strong earthquake occurred in the Longmenshan fault zone after the "5·12" Wenchuan earthquake.The Lushan earthquake triggered more than 1800 harmful geological hazards,which increased by 14 percent than before the earthquake.The areas where geological hazards occur high frequently are located in that with Ⅷ and Ⅸ grade intensity,including Longmen-Baosheng-Taiping-Shuangshi and Daxi-Lingguan-Zhongba-Muping.The main types of geological hazards include shallow landslides and collapses,rockfall,particularly the collapsed bodies.Their failure mode is vibration-fracturing-sliding,vibration-fracturing-scattered and vibration-eccentric rolling.Besides the earthquake triggering effect the earthquake geological hazards are controlled by the prominent characteristics of steep topography,terrain and elevation amplification effect.And the weak lithology and the strongly weathered unloading rock mass are the material basis of geological hazards.According to the field survey,many geological hazards are directly caused by the earthquake casualties.The range of the earthquake collapse and rockfall danger zone is Dmax=(0.7~1.3)Hmax and the rockfall movement distance is dmax≈1.1404Hmax+6.42.These are consistent with the research results of the Wenchuan earthquake’s collapse.