【摘要】 地震预警技术是减轻地震灾害损失的有效手段之一.地震预警系统中,地震震级计算是最重要也是最困难的部分之一.利用日本KiK-net台网和四川汶川余震共142次地震事件的记录,分别采用τc和Pd方法统计得到了地震预警震级的计算公式,震级计算的方差分别为0.62和0.56个震级单位.为消除震级计算过程中出现的震级饱和现象,作者拓展了Pd方法,提出了一套对位移幅值连续追踪测定的算法.当时间窗长度为10s时,采用该方法的震级计算方差仅为0.37个震级单位,充分满足地震预警系统的需求.同时,该方法也实现了信息的连续过渡,提高了对现有信息的利用率.最后,还对位移幅值Pd用于地震动峰值PGV的估计以及不同特征参数间的相容性等内容进行了讨论.更多还原

【Abstract】 Earthquake early warning(EEW) is one of the effective ways to reduce earthquake damage.Earthquake magnitude estimation is the most important and also most difficult part in the whole EEW system.Based on 142 earthquake records from KiK-net in Japan and aftershock records of the great Wenchuan earthquake in Sichuan,China,we worked out the magnitude estimation relationships by using τc and Pd methods,with corresponding variances of 0.62 and 0.56,respectively.In order to remove the effect of magnitude saturation,we expanded the Pd method and proposed a new method of continuously calculating the peak displacement.When the time window is 10 s,the variance of magnitude estimation is reduced to 0.37,fully meeting the need of EEW systems.Meanwhile,our method realized the continuous transition of different information,and improved the utilization of seismic records.We also discussed the relation between Pd and PGV,and the compatibility between different characteristic parameters.更多还原