关键词: 地震, 次生地质灾害, 分布, 形成条件

Abstract:

The earthquake secondary geological disasters refer to the geological disasters induced by earthquake,including mainly landslide,collapse,and also ground caving in and soil liquefaction,etc. The earthquake secondary geological disasters not only aggravate the earthquake losses,but also bring on difficulties in disaster relief and post-quake reconstruction. More than 20 provinces(municipalities and autonomous regions)in China have been subject to earthquake secondary geological disasters but with various degrees in different regions. The areas of Shaanxi,Gansu,Ningxia,Sichuan,Chongqing,Yunnan and Tibet in the central part of Chinese continent are the most seriously affected,forming a NNE-trending high danger zone. The geologic and geomorphic conditions for generating earthquake secondary disasters are basically the same with that of general geological disasters,but the trigger factor for the former is earthquake. Secondary geological disasters are likely to happen in areas of M≥5.0 and seismic intensity ≥Ⅵ,and the higher the earthquake magnitude and intensity,the more serious the secondary geological disasters. The damage caused by earthquake secondary geological disasters is similar compared with other geological disasters,but the chance of occurrence of the former is smaller.

Key words: earthquake, secondary geological disaster, distribution, formation condition