汶川8.0级地震触发地质灾害发育分布规律研究  

Development and Distribution Rules of Geohazards Induced by Wenchuan M8.0 Earthquake

作　　者：梁京涛[1,2] 王军[2] 汪友明[2] 王猛[2] 刘斌[2] 杨磊[2] 

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [2]四川省地质调查院,四川成都610081

出　　处：《灾害学》2015年第1期63-68,共6页Journal of Catastrophology

基　　金：中国地质调查局西南地区重大地质灾害隐患遥感综合调查评价(12120113010000);中国地质调查局汶川地震灾区高位泥石流遥感调查评价(1212011220149);四川省地质矿产勘查开发局"四川地震灾区高位泥石流遥感早期识别及风险评估"

摘　　要：汶川8.0级地震共触发地质灾害13759处，灾区39个县（市、区）的地质灾害发育密度达14.02处／100 km2。该文采用以上数据，探讨了地震地质灾害的区域性分布规律，着重分析了地震地质灾害与地震烈度、地层岩性、地形坡度及海拔高程等影响因素的关系，得出以下认识：①研究区地震地质灾害主要分布于发震断裂两侧30 km范围内，在区域上表现出沿龙门山中央断裂呈“带状”分布、沿水系呈“线状”或“串状”分布的特征；②地震地质灾害发生的斜坡部位与微地貌形态有着密切的关系，地震地质灾害多沿山脊线或分水岭部位高位分布；③地震地质灾害的发育程度与地震烈度呈正相关关系，地质灾害的发育密度，随着地震烈度等级的降低而降低；④地震地质灾害主要发育在较软岩岩组和坚硬岩岩组内，在地震力作用下，软岩岩组内更容易引发滑坡灾害，崩塌多发育在坚硬岩组内；⑤在海拔1000～1500 m，斜坡坡度30＆#176;～50＆#176;区域范围内是地质灾害集中发育区，不同坡度范围内，地震地质灾害表现出不同的优势发育类型。Wenchuan M8.0 earthquake triggered 1 3759 geological disasters in total,and the geological disas-ter development density of 39 counties （cities,districts）is 1 4.02/1 00 km2 .According to the above data,regional distribution pattern of seismic and geological disasters are discussed.It is mainly focused in the analysis on the rela-tionship between geological disasters and the influencing factors including earthquake intensity,lithology,terrain slope and altitude,and the following conclusions are derived：① In the research area,the geological disasters mainly distributed along both sides of the coseismic fault and within 30 km of the coseismic fault.On the regional scale,the distribution pattern appears zonal distribution along Longmenshan central fault,and linear distribution or string-like distribution along the water system.② The slope position of geological disasters has close relationship with micro-landforms,and the geological disasters distributed mainly on the high position along the ridgelines and watersheds.③ The development level of geological disasters has positive relationship with earthquake.The devel-opment density of geological disasters decreases as the earthquake intensity decreases.④Geological disasters main-ly develop in relative soft rock formations and hard rock formations.By the effect of earthquake force,landslides u-sually occur in soft rock formation,and rock falls often develop in hard rock formation.⑤ Geological disasters mainly develop within the area where the altitude is from 1 000 to 1 500m,and the slope is from 30＆#176;to 50＆#176;.In dif-ferent ranges of slope,geological disasters demonstrate different advantage developmental patterns.

关 键 词：汶川地震 地震地质灾害 分布规律 遥感 

分 类 号：P642[天文地球—工程地质学] X43[天文地球—地质矿产勘探]