摘要
Based on the forming mechanism of seismic hazard risk, we established a seismic vulnerability curve on population and determined earthquake occurrence parameters. We then assessed the risk of seismic hazard mortality at the county level across China using the assessment model, and analyzed spatial patterns. We adopted past, present, and future disaster-breeding materials to assess the probability of earthquakes. In order to determine the earthquake parameters of 2355 counties accurately, we integrated history seismic intensities, seismic activity fault belts distributions and seismic peak ground acceleration. Based on data of seismic disasters from 1990 to 2009 in China, linear fitting between seismic intensities and mortalities was performed. And a vulnerability curve of seismic mortality, which was appropriate for seismic risk assessment, was established. Seismic mortality risks were assessed quantitatively at the county level using the model and the spatial patterns were analyzed. Seismic mortality risks of 2355 counties with intensities from Ⅴ to Ⅺ were analyzed thoroughly. This study indicates that under different seismic intensities, China’s eastern and central regions are generally confronted with higher risk than western regions. High-risk areas are scattered in Shandong and Jiangsu, northern Anhui and eastern Heilongjiang and Jilin, where populations are dense and the environment is conducive to disasters. Risk- free areas displayed patchy distributions nationwide, and patterns were mostly unchanged.
基于地震灾害风险形成机理,在建立人口震害脆弱性曲线与确定地震发生参数的基础上,本文利用评估模型对我国Ⅴ-Ⅺ地震烈度下各县域单元的人口死亡风险进行评估并分析其空间分布格局。主要研究内容有:(1)首次采用基于过去—现在—未来的多方面地震孕灾环境资料来处理地震发生的可能性。具体综合历史地震综合烈度、地震活动断裂带分布、地震动峰值加速度三方面来确定全国2355个县域单元的地震发生参数;(2)利用1990-2009年我国历史地震灾情数据,对地震烈度与人员死亡率之间进行线性拟合,建立适合我国地震灾害风险评估的震害人口死亡脆弱性曲线;(3)利用震害风险评估模型对我国各县域单元的人口死亡风险进行定量评估,并分析风险空间分布格局,彻底摸清Ⅴ-Ⅺ地震烈度下我国各县域单元的地震灾害人口死亡风险。研究表明:在不同地震烈度下,我国广大的东、中部地区面临更高的风险,而西部的人口死亡风险相对较低。高风险区域呈零星状分布于山东与江苏大部、安徽北部、黑龙江与吉林东部等人口分布较密集且孕灾环境发育完备的区域。而无风险区域在全国范围内呈斑块状散布,分布格局基本保持不变。
基金
National Science and Technology Support Program (Grant NO.2008BAK50B05, 2008BAK50B06)