基于信息论方法分析我国典型地震动衰减关系

Analysis of the typical ground-motion attenuation relationships in China based on information-theory

近年来我国强震数据逐渐增多,为了比较和分析我国的几个典型地震动衰减关系,采用一种信息论方法,基于实际地震动记录,计算选取的地震动衰减关系模型的对数似然函数值,通过对数似然函数值对模型进行排序,并给出相应的权重及排名,分析了不同衰减关系对地震动的预测能力。研究表明:针对于我国西部强震数据,基于强震动记录建立的衰减关系的预测结果更接近于实测地震动数据。研究结果可为地震动记录信息不完善或缺乏强震数据地区的地震动衰减关系选取提供参考。

In recent years, the data of strong ground motion in China have increased gradually. In order to compare and analysis the typical ground motion attenuation relationships in China. Based on the real strong motion records, an information-theory based method is used to calculate the log-likelihood function value of the typical attenuation models, then the models are ranked by the log-likelihood function value, and the corresponding weights and the rankings are given. Through analyzing the predictive abilities of the selected attenuation models, results show that for the strong motion data in Western China, the predicted ground motion by attenuation relationship based on strong motion are closer to the measured ground motion than those by the other methods. This research results provide reference for selecting attenuation relationships for regions lacking of strong motion records or complete related information.