基于GIS和logistic模型的地震滑坡致死人数快速评估方法  

A METHOD FOR RAPID ASSESSMENT OF DEATH TOLL FROM EARTHQUAKE-INDUCED LANDSLIDE BASED ON GIS AND THE LOGISTIC MODEL

作　　者：白仙富[1,2] 聂高众[3] 叶燎原[1] 戴雨芡[1] 余庆坤[2] BAI Xian-fu;NIE Gao-zhong;YE Liao-yuan;DAI Yu-qian;YU Qing-kun(Faculty of Geography Science,Yunnan Normal University,Kunming 650050,China;Yunnan Earthquake Agency,Kunming 650224,China;Institute of Geology,China Earthquake Administration,Beijing 100029,China)

机构地区：[1]云南师范大学地理学部,昆明650500 [2]云南省地震局,昆明650224 [3]中国地震局地质研究所,北京100029

出　　处：《地震地质》2021年第5期1250-1268,共19页Seismology and Geology

基　　金：国家重点研发计划项目(2018YFC1504503);中国地震局地质研究所基本科研业务专项(IGCEA2106);云南省地震局科技专项(2018ZX03)共同资助。

摘　　要：科学评估地震地质灾害可能造成的人员伤亡数量,是提高地震人员伤亡评估准确性和完善地震灾害损失评估体系的重要因素之一,然而,这一问题却至今没有完善的解决方案。文中提出了一种基于GIS和logistic模型的地震滑坡致死人数快速评估方法,尝试在此方面开展研究。该方法包括3个步骤:1)在GIS中将评估区划分为1km×1km的网格单元,把网格范围内的人口数量赋值给网格单元作为其人口属性信息;2)基于回归的logistic模型,根据网格单元的地震滑坡危险性属性计算各网格单元的地震滑坡致死率;3)计算各公里网格单元的地震滑坡致死人数,然后进行整个研究区的地震滑坡致死总人数评估。利用本方法,以2014年“8·3”鲁甸M_(S)6.5地震,2012年“9·7”彝良MS5.6、MS5.7地震和2008年“5·12”汶川M_(S)8.0地震的3个地震灾区为研究区,进行了地震滑坡致死人数测试。其中,基于鲁甸震例构建地震滑坡致死人数快速评估方法并评价其有效性,利用彝良和汶川震例测试该方法在更广范围内开展地震滑坡致死人数快速评估时的外延性和适用性。基于文中提出的模型评估得到鲁甸地震灾区因地震滑坡导致的死亡人数为233人,与实际因地震滑坡导致的死亡和失踪共250人相比少17人,死亡总数评估误差率为6.80%;公里网格单元死亡人数评估结果的Kappa检验值为0.912,表明用所建模型计算的死亡人数与实际死亡情况的一致性较好,模型具有很好的统计学意义。而外延适用性分析结果显示:汶川地震时滑坡导致的死亡和失踪合计约20000人,模型评估的结果为18732人,死亡总数评估的误差率约为6.5%;模型评估的彝良地震灾区地震滑坡致死人数为48人,比实际死亡人数少11人,死亡总人数评估误差率为18.64%,公里网格单元死亡人数评估结果的Kappa检验值为0.889。实例研究结果表明:在允许存在一定误差的前提�The scientific assessment is one of the cornerstones for improving the earthquake disaster loss assessment system and the accuracy of the assessment of casualties caused by seismogeological hazards.However,this question has long been plaguing scientists engaged in the earthquake disaster risk assessment.So far there is no better solution yet.To solve this problem,the authors develop a new method for rapid assessment of the death toll caused by the earthquake-induced landslide based on GIS techniques and the logistic regression model.The method mainly consists of three procedures:1)On GIS platform,the study area is divided into 1km×1km grid cells,and the number of the people in each cell is assigned to the cell as its population attribute;2)based on the cell’s earthquake risk attribute,the landslide death rate in each cell is calculated by using the logistic regression model,and 3)by adding the death number in each cell,the total death toll in the study area are got.To test our new model,we select four earthquake events for case study:the 2014 Ludian,Yunnan M_(S)6.5 earthquake;the 2008 Wenchuan,Sichuan M_(S)8.0 earthquake,and the 2012 Yiliang,Yunnan M_(S)5.6&5.7 double earthquakes.Here,the Ludian earthquake case is for testing the effectiveness of our new model.The other two cases serve for testing the practicability of our model for the future earthquake disasters in other places in China.Our logistic model of the landslide death-rate in the kilometer grid shows that the absolute values of the coefficients of the 2 impact factors are relatively large.These 2 factors,which indicate respectively the highest landslide-hazard grade and the lowest one,are playing critical roles in deciding the death toll from earthquake-induced landslide.In each kilometer grid,when the impact factors of the landslide-hazard grade are 5,4,and 3,their corresponding coefficients are respectively 0.04077,0.03130,and 0.01365.If the number of the sub-grids corresponding to these 3 impact factors rise,the death rate will accordingly rise.

关 键 词：地震滑坡 致死人数 评估模型 公里网格 

分 类 号：P315.9[天文地球—地震学]