摘要
为研究九寨沟地震前后次生地质灾害分布特征,本文应用Arcgis软件平台,对研究区震前472处和震后新增272处地质灾害的分布特征进行统计分析,得出以下结论:(1)80.88%震后新增灾害点分布在距震中30km范围内,灾害点密度随震中距的增大而减小。67.28%新增灾害点分布在烈度Ⅷ度及以上区域,灾害点密度随地震烈度的降低而减小。(2)地震前后灾害点均集中分布在距河流300m范围内,各占总数的79.45%和81.25%,灾害点数量与密度均随着与河流距离的增加而显著降低。(3)地震前后在高程2 000～2 600m灾害点数量最多,高程2 600～3 200m次之。(4)地震前后分布在15°～45°坡度范围内灾害点数量分别占总数的82.2%和84.2%。(5)滑坡、崩塌等次生地质灾害为泥石流发育提供较好的物源条件,在未来3～5a雨季应切实做好泥石流防治工作。
In order to study the distribution of secondary geo-hazards before and after jiuzhaigou earthquake,this paper statistically analyzed the distribution of 472 geo-hazards before the earthquake and the 272 new geo-hazards and main influencing factors at the study area by Arcgis.The results show that：1.80.88% of new geo-hazards distributed within 30 km from the epicenter,and the density decreased with the increase of epicentral distance.2.Pre-earthquake and post-earthquake new geo-hazards within a distance of less than 300 maway from river,accounting for 79.45% and 81.25% of the total number of disasters respectively.the number and the density decreased significantly with the distance from the river.3.New geo-hazards are mainly shallow landslide and collapses,and well developed in limestone,sandstone and quaternary soil.4.The most geo-hazards distributed in the elevation of 2 000～2 600 mup to 2 600～3 200 m.5.The number of pre-earthquake and added geo-hazards distributed in the slope of 15°～45° accounted for 82.2% and 84.2% of the total respectively.6.Secondary geo-hazards provide better source condition for the development of debris flow.In the next three to five years,the debris flow prevention and control should be effectively implemented during the rainy season.
作者
刘果
张友谊
张珊珊
叶小兵
袁亚东
LIU Guo;ZHANG You-yi;ZHANG Shan-shan;YE Xiao-bing;YUAN Ya-dong(Southwest University of Science and Technology,School of Civil Engineering and Architecture,Mianyang 621010,China)
出处
《地质灾害与环境保护》
2018年第3期1-4,共4页
Journal of Geological Hazards and Environment Preservation
关键词
九寨沟地震
地质灾害
分布规律
对比分析
Jiuzhaigou earthquake
geological hazard
distribution law
comparative analysis
