【摘要】 2008年汶川5.12地震触发了大量滑坡,这些滑坡所造成的损失甚至超过地震本身。系统的滑坡编目是进行滑坡研究的基础技术手段,能为滑坡量化研究提供有效数据。映秀极震区是地震滑坡分布较为集中的区域。基于高精度卫星和航拍影像遥感和现场调查,获得映秀极震区约109.3km2范围内共1948处地震滑坡的位置、类型及其基本几何特征,并利用GIS软件建立了地震滑坡编目数据库。在此基础上,将地震滑坡编目数据同坡向、坡角、距山脊距离、地质单元与岩性、震中距、距发震断裂距离等环境因子进行叠置分析。分析结果表明:编目区内地震滑坡多分布在坡角为30°～50°的区域,其密度与坡度有较强的正相关性;山脊附近区域的地震滑坡密度较大,说明这些区域对地震波的放大效应是造成坡体破坏的重要原因;彭灌杂岩体区的地震滑坡发育程度比沉积岩区高;震中距、距发震断裂距离与地震滑坡密度呈单指数负相关关系,与已有研究成果具有较好吻合度,且发震断裂上盘地震滑坡发育程度高于下盘。更多还原

【Abstract】 A number of landslides were triggered by the Wenchuan earthquake on May 12 2008.The damage caused by these landslides was even more than that by earthquake.Systematic landslides inventory,as a basic technique for landslide study,can provide applicable data to quantify the study of landslides.A lot of earthquake-induced landslides were concentrated in Yingxiu meizoseismal area of 5.12 Wenchuan Earthquake.By means of post-earthquake aerial photo and satellite imagery interpretation and field investigation,this paper gets the information including locations,types and morphometry about 1948 earthquake-induced landslides within the Yingxiu Meizoseismal area(about 109.3 ㎞2) and inventoried them with GIS software.Then,overlay analyses are used between these landslides inventory data and environmental factors such as slope aspect,slope angle,distance from ridge,geologic units and lithology,distance from epicentre and seismogenic fault.The results show that: Landslides are triggered by earthquake scatter predominantly in the range of 30°~50°,and the landslide density is positively correlated with slope angle.Areas nearby ridge are of high landslide density indicating that amplification effect of ridge on seismic wave is an important reason of slope failure.Earthquake-induced landslide development level in Pengguan complex is higher than that in sedimentary petrologic province.Landslide density is the single exponential negative correlation with distance from epicentre and seismogenic fault indicating that earthquake-induced landslide development level in hanging wall of seismogenic fault is higher than that in footwall,and the results predicted by regression correlation agree with the existing research findings.更多还原