山区地质灾害时空分布规律及影响因素分析——以四川省马边县为例

山区地质灾害不仅破坏山区环境，损毁耕地、房屋及公共设施，还威胁人民的生命和财产安全，制约山区经济发展.为减轻地质灾害的发生和降低人类生命财产的损失和环境的破坏，提高马边县地质灾害区的防灾减灾能力，通过野外调查、数据统计和GIS空间分析等方法，运用定性和定量结合法研究了马边县地质灾害时空分布与地形地貌、地质构造、降雨条件等3大类和海拔、坡向、坡度、坡型、岩性、断裂、降雨和人为活动8小类因素的关系.结果表明：1）马边县地质灾害以滑坡灾害为主，崩塌次之，泥石流最少，在时间上和空间上分布具有不均匀性；2）地形地貌因子敏感区间为海拔700～900 m之间，坡向为东和东南向，坡度为20～25°之间，坡型为凸型坡为主；3）地质构造因子敏感区间是岩性以泥岩为主，构造带以距离断层中心线小于1 km范围为主；4）降雨量的敏感区间在低山区为1 100～1 300 mm之间，中高山区为1 300～1 500 mm之间；5）人为活动因素已不可忽视．

SPATIOTEMPORAL DISTRIBUTION AND INFLUENCING FACTORS OF GEOLOGICAL DISASTERS IN MOUNTAINOUS AREAS: A Case Study of Mabian County in Sichuan Province

To reduce the occurrence of geological disasters, minimize the loss of human life and property and the destruction of environment, and improve the ability of disaster prevention and reduction in geological disaster area, through field survey, data statistics and GIS spatial analysis, the qualitative and quantitative combination method is used to study the relationship between the spatiotemporal distribution of geological disasters and three categories of factors, i.e. landform, geological structure and rainfall, as well as eight subcategories such as elevation, slope aspect, slope gradient, slope type, lithology, fault, rainfall and human activities. The results indicate that the geological disasters in Mabian County are mainly landslides, followed by collapses, and least debris flows, showing uneven spatial and temporal distribution. The sensitive intervals of topographic factors include the elevation of 700-900 m, slope aspect of east and southeast, slope gradient of 20-25° and slope type of mainly convex slope. The sensitive geological structural factors include the lithology of mainly mudstone, and tectonic zones less than 1 km away from the fault centerline. The sensitive interval of rainfall is 1100-1300 mm in low mountain area and 1300-1500 mm in middle and high mountain areas. Human activity is also a nonnegligible factor.