【摘要】 本文提出了汶川地震高烈度区11县域(汶川、北川、绵竹、青川、茂县、都江堰、安县、什邡、彭州、平武和文县)地质灾害区域预警方法,包括发育度分布、潜势度区划与危险度区域预警。研究区地震后地质灾害类型由震前的滑坡、崩塌为主演变成泥石流为主,震后灾害数量是震前的8.7倍,地质灾害极高发育区分布面积204.32 km2,灾害点密度达到8.11起/km2,主要位于什邡、绵竹、安县、汶川及文县境内。基于地形坡度、坡向、高程、地貌、岩性、断裂构造、烈度区划、年均雨量、水系、人类工程活动(道路)及地质灾害发育度分区指数等11项因子,计算潜势度并划分为四个等级,极高潜势区面积占全区面积的4.17%,灾害点数占11县域灾害总数的44.15%,灾害点平均密度达到2.44起/km2,地质灾害极高、高潜势区呈线状、局部面状分布,在都江堰、彭州、什邡、绵竹、安县等地呈面状分布,在北川、平武、青川、文县等地呈条带状分布。将地震、汛期降雨和日降雨作为引发因子,基于潜势度评价,开展地质灾害危险度区域预警研究,地震引发地质灾害高危险度的地区主要集中在南部的汶川、都江堰、彭州、什邡、绵竹以及北部的青川、文县等地; 2013年汛期降雨引发地质灾害危险度高的地区集中在都江堰、绵竹、安县、北川、平武和文县等地; 2013年7月9日降雨引发地质灾害危险度高的地区集中在都江堰、彭州、什邡、绵竹和安县等,三种引发因子引发的实际灾害点与危险度预警的重点区域比较吻合,研究方法可以作为地震引发地质灾害预测、汛期(5～9月)地质灾害趋势预测和短临(1～3日)地质灾害区域预警提供科学支撑。更多还原

【Abstract】 The regional early-warning methods for geological hazards were studied in 11 counties of Wenchuan earthquake high seismic intensity area(Wenchuan,Beichuan,Mianzhu,Qingchuan,Maoxian,Dujiangyan,Anxian,Shifang,Pengzhou,Pingwu and Wenxian).The research contents included developmental grade,potential grade and dangerous grade early warning.The types of geological hazard change from landslide and collapse before earthquake to debris flow after earthquake.The number of hazards after earthquake is 8.7 times before earthquake.The distribution area of high developmental grade zone is 204.32 km2,there were 8.11 hazards per square kilometer,and locating in Shifang,Mianzhu,Anxian,Wenxian,and Wenxian.The potential grade indexes of geo-hazards were worked out according to 11 assessment factors such as landform gradient,aspect,elevation,stratigraphic layers,topographic feature,fault structure,seismic intensity,average annual precipitation,river system,human engineering activities(roads) and developmental grade index,etc.The area of extremely high potential grade accounted for 4.17% of the total area.The number of hazard points accounted for 44.15% of the total hazards.There are 2.44 hazards per square kilometer.The areas of high potential grade were facial distribution and locally linear distribution.The early warning of dangerous grade included 3 factors,which were seismic activity,rainfall in flood season and daily precipitation.The high dangerous grade areas caused by the earthquake were mainly in Wenchuan,Dujiangyan,Pengzhou,Shifang,Mianzhu,Qingchuan and Wenxian,etc.The high dangerous grade areas caused by the rainfall in flood season of 2013 were Dujiangyan,Mianzhu,Anxian,Beichuan,Pingwu and Wenxian,etc.The high dangerous grade areas caused by the daily precipitation at July 9,2013 were Dujiangyan,Pengzhou,Shifang,Mianzhu and Anxian,etc.The actual hazard points of the 3 triggering factors were in good agreement with the key areas of the dangerous grade early warning.The research method in this paper can be used as a scientific support for geological hazard early warning triggered by earthquake,rainfall in flood season,and daily precipitation.更多还原