τc方法在内蒙古地区预警震级计算中的应用

Application of τc Method in the Early Warning Magnitude Calculation in Inner Mongolia Region

摘要:

地震预警技术是减轻地震灾害的有效手段之一，而在预警系统中，震级的测定是最重要，也是最困难的。考虑到地震预警震级估算方法的区域性特点，本文利用内蒙古测震台网2016~2018年M_L ≥ 2.0地震波形数据共120条，分别采用P波3s时间窗内垂直向位移时程和P波全波段垂直向位移时程计算特征周期参数值，得到了地震预警震级的计算公式，并对其结果进行对比分析。结果显示，采用P波全波段关系式得到的结果较采用P波3s固定时间窗计算值收敛性更好，关系式拟合相关系数更接近1，能够对预警地震震级做出较好的估计。同时结合数据处理结果，探讨了地震预警的警报快速性和准确性之间的关系。

Abstract:

Earthquake early warning(EEW)is one of the effective means to reduce earthquake disaster. Magnitude measurement is the most difficult and important parameter in the early warning system. Considering the regional characteristics of magnitude estimation method for earthquake early warning,we used 120 seismic waveform data of M_L ≥ 2.0 and above of Inner Mongolia Seismological Network from 2016 to 2018,and calculated the characteristic period parameters by using the vertical displacement time history in P-wave 3S time window and the vertical displacement time history in P-wave full band,respectively. The formulas for calculating earthquake warning magnitude are obtained,and the results are compared and analyzed in this paper. We found that the results obtained by P-wave full-band relation are more convergent than those calculated by P-wave 3S fixed time window,and the correlation coefficient fitted by the relation is more close to 1,which can make a better estimation of the magnitude of early warning earthquakes. Finally,combined with the data processing results,the relationship between the speed and accuracy of earthquake early warning is discussed.