基于历史地震烈度资料的云南地区地震危险性评估  

Seismic Hazard Assessment of Yunnan Based on Historical Seismic Intensity

作　　者：文雯[1] 隋明坤 庄儒新[1] 王珏[1] 陆斌斌 李圣 WEN Wen;SUI Mingkun;ZHUANG Ruxin;WANG Jue;LU Binbin;LI Sheng(Yunnan Earthquake Agency,Kunming 650224,Yunnan,China)

机构地区：[1]云南省地震局,云南昆明650224

出　　处：《地震研究》2023年第3期422-429,共8页Journal of Seismological Research

基　　金：云南省地震局地震自立科技专项基金(2022ZLZX03);云南省第一次全国自然灾害风险普查项目.

摘　　要：将云南地区按照0.1°×0.1°划分网格,收集了1713—2022年6级以上和1900—2022年5级以上(或震中烈度≥Ⅵ度)地震的烈度资料,分析这些地震对各网格的影响,筛选影响烈度I≥Ⅴ度的地震组成地震烈度资料数据库;建立地震烈度与其发生频率(或重复周期)之间的关系,对云南地区的地震危险性进行评估,给出了每个网格发生某一烈度的重复周期,同时预估了未来50年发生某一烈度的超越概率,并利用烈度与加速度的对应关系,给出了50年超越概率10%的地震动峰值加速度(PGA);将计算结果与云南地区地震构造以及中国地震动参数区划图进行比较。结果表明:重复周期较短(重复频率较高)的区域与活动断裂展布的密集程度是基本吻合的;50年超越概率10%的峰值加速度分布区域与中国地震动参数区划图的PGA高低区域分布大体一致,从各市(县)的尺度上看,又有所不同,有的县(市)的PGA比区划图云南部分给出的结果高,有的则偏低。Firstly,we collected the earthquake-intensity data of the M 6.0 earthquakes in 1713-2022,and the M 5.0(intensity≥Ⅵ)earthquakes in 1900-2022.Secondly,we divided Yunnan area into 0.1°×0.1°grids to analyze the impact of these historical earthquakes on the grids.We established the relation between the intensity and its occurrence frequency(or return period).Then we assessed the probabilistic seismic hazard in Yunnan,and obtained the return period of a certain intensity in each grid,and assessed the exceedance probability of a certain intensity in 50 years.Thirdly,based on the relations between the intensity and the acceleration,we obtained the exceedance probability of the peak ground acceleration(PGA)in 50 years in Yunnan.On this basis we analyzed the relations between the return period and the seismogeological structures in Yunnan.And we compared our PGA results with the ones provided by the Seismic Ground Motion Parameters Zonation Map of China.We found that in the zones with the short return period(or high repetition frequency),the active faults were densely distributed.The distribution of the exceedance probability of the PGA in 50 years which obtained in this paper is generally in line with the distribution of the exceedance probability of the PGA in 50 years given by the Seismic Ground Motion Parameters Zonation Map of China.Specifically,in some cities or counties,the PGA s obtained in this paper are larger than the ones given by the Seismic Ground Motion Parameters Zonation Map of China;in other cities or counties,the PGA s obtained in this paper are smaller than the ones given by the Seismic Ground Motion Parameters Zonation Map of China.

关 键 词：地震烈度 地震危险性评估 地震灾害风险 重复周期 超越概率 云南地区 

分 类 号：P315.91[天文地球—地震学]