基于华北区域地震活动性分布的地震危险性评价模型

采用了分布式地震活动性模型. 该模型无需潜在震源区划分，同时简化了地震危险性概率分析方法. 根据破坏性地震目录建立了3个地震活动性模型，利用高斯光滑函数获得了华北区域内的a值分布特征，使用3种典型的衰减模型，分别计算了50年内超越概率10%， 5%和2%的地震动峰值加速度分布. 其分析结果显示了峰值加速度分布特征与我国第四代区划图大体一致，特定地震活动区（太原、 石家庄等地区）的峰值加速度略高于第四代区划图的结果，而这种峰值加速度分布特征与该地区较高的地震活动性特征是一致的. 概率危险性曲线结果表明，唐山、太原和北京等地区的潜在地震危险性比华北区域内其它城市高. 

Seismic hazard estimation based on the distributed seismicity in northern China

In this paper,we have proposed an alternative seismic hazard modeling by using distributed seismicites.The distributed seismicity model does not need delineation of seismic source zones,and simplify the methdology of probabilistic seismic hazard analysis.Based on the devastating earthquake catalogue,we established three seismicity model,derived the distribution of a-value in northern China by using Gaussian smoothing function,and calculated peak ground acceleration distributions for this area with 2%,5% and 10% probability of exceedance in a 50-year period by using three attenuation models,respectively.In general,the peak ground motion distribution patterns are consistent with current seismic hazard map of China,but in some specific seismic zones which include Shanxi Province and Shijiazhuan areas,our results indicated a little bit higher peak ground motions and zonation characters which are in agreement with seismicity distribution patterns in these areas.The hazard curves have been developed for Beijing,Tianjin,Taiyuan,Tangshan,and Jinan,the metropolitan cities in the northern China.The results showed that Tangshan,Taiyuan,Beijing has a higher seismic hazard than that of other cities mentioned above.