【摘要】 地震预警技术(EEW)是目前防震减灾相对有效的方法之一,研究震源破裂初始段波形信息可为EEW系统的震级实时估算提供理论支持。本文结合P波初动波形特征,分别计算日本和中国地震的强震动记录的位移峰值曲线,对比各震级的位移峰值均值曲线的特征,然后利用分段函数模型进行拟合,量化初动上升斜率B1和上升时间T1等特征参数,并统计此类参数与震级相关性。结果表明:当不考虑幅值差异时,随震级的增大,P波初动波形由简单变复杂,均值曲线初始上升段斜率逐级降低,初始上升时间变长,B1等特征参数与震级具有很好的相关性。此外在不同地质构造环境中地震的强震动记录此特征基本一致。因此P波初始段的特征参数可用于估算震级大小,同时证实震源初始破裂过程的信息可反映最终地震的强弱。更多还原

【Abstract】 Earthquake early warning(EEW) technology is an effective method for earthquake prevention and mitigation. Waveform information in the initial source rupture stage is analyzed to provide theoretical support for the real-time magnitude estimation in the EEW system. In this paper, combining the characteristics of the P-wave initial motion waveform, we calculate displacement peak curves of strong earthquake records selected from earthquake events in Japan and China, compare the characteristics of displacement peak mean curves for magnitude, quantify the characteristic parameters by fitting them with a piecewise function model, such as the initial rising slope B1 and the rising time T1,and calculate statistical correlation of them with magnitude. The results show that with the magnitude increasing the initial P-wave waveform changes from simple to complex when ignoring amplitude difference, the initial rising slope of mean curve is gradually reduced, and the initial rise time becomes longer. At the same time, the quantitative parameters, such as B1, of the initial rising segment have a good correlation with magnitude. In addition, the characteristics of the initial segment in strong motion records selected from different geological tectonic are basically consistent. Therefore, the characteristic parameters of initial P-wave can be used to estimate the magnitude which confirms that the information from the initial source rupture reflect the final earthquake strength.更多还原