Automatic Identification of Direct P-wave First Motion in Earthquake Early Warning

Through the combination of the STA/LTA method, the fixed time window AIC method, the STA/LTA method and the AIC criterion, and the W-AIC method, based on the wavelet coefficient, the automatically identification of direct P-wave first motion was studied. Based on the characteristics of the seismic records studied, the appropriate calculation parameters were selected and the error was compared. The results show that: the combination of STA/LTA and AIC criterion, on the one hand, can avoid the error identification of STA/LTA method, and on the other hand, it can solve the problem that the combination of AIC has poor effect on the identification of small initial amplitude, so as to achieve more accurate seismic phase identification.