中强地震活动区地震年平均发生率确定方法的比较

Methods on the calculation of annual seismic activity rate in moderate strong seismicity region

摘要:

目前确定地震活动性参数的方法有2种,即潜在震源区划分法和格点空间光滑法。本文针对格点空间光滑法,重点介绍了高斯空间光滑法及其改进后的方法,并对比分析了这些方法的优缺点及适用性;然后以华中为研究区,分别采用高斯空间光滑法和潜在震源区法建立地震活动性模型计算地震年平均发生率,并利用概率地震危险性分析方法计算地震危险性,对比两种方法所得区划结果的差异并分析了引起差异的原因。结果表明：空间光滑法适用于中强地震活动区地震危险性或由背景地震引起的地震危险性的计算;潜在震源区划分法适用于考虑明确的发震构造的地震危险性。将2种方法相结合,综合考虑地震和已知构造信息是判断中强地震活动区地震危险性的可行方法。

Abstract:

Two kinds of methods for the determination of seismic parameters are presented in this paper,i.e.seismic source zoning method and grid-spatially smoothing method.The Gaussian smoothing method and the modified Gaussian smoothing method are described in detail,and a comprehensive analysis of the advantages and disadvantages of these methods are made.Then we take the central China as the study region,and use the Gaussian smoothing method and seismic source zoning method to build the seismic model for the calculation of annual seismic activity rate,calculate the seismic risk from the models to get the ground motion acceleration zoning map.The differences between the maps from the models are discussed and the causes are investigated.The results show that the spatially smoothing method is suitable for the seismic hazard estimate of moderate strong seismicity regions or the seismic hazard caused by background seismicity,and the seismic source zoning method is suitable for the estimate of seismic hazard caused by determined seismotectonics.The combination the two methods and the consideration of seismicity and known seismotectonics make up a feasible method to estimate the seismic hazard of moderate strong seismicity region.[著者文摘]