Study On Automatic Recognition Of Seismic Arriving Time And Rapid Estimation Of Magnitude In Earthquake Early Warning

As a very important means for preventing and reducing earthquake disaster, earthquake early warning (EEW) has received considerable attention from international society in recent years. The rapid magnitude estimation of earthquake early warning is revolved in this paper as follows:1. Basic idea of the earthquake early warning, domestic and foreign earthquake early warning system construction present situation, as well as technique advances in relative research are introduced.2. On the basis of seismic phase recognition by using STA/LTA method, the method by using linearity fitting from arriving time at threshold to actual arriving time of seismic wave is studied. The application results of real seismic records indicate that this method has higher identification accuracy.3. Two estimation methods, the instantaneous predominant period method and the average period method, commonly used in earthquake early warning research are detailed introduced. In this article, the two methods are compared using actual earthquake records, and the results indicate that the average period method is superior to the instantaneous predominant period method as well as the results after data filtered are more accuracy than the un-filtered estimate results.4. In this paper, based on the B-Δmethod of the Japanese scholar Odaka, we propose a new earthquake magnitude estimation method united amplitude and period, by taking the average period as a parameter. The results of actual earthquake records indicate that, the improved method has less discrepancy and simultaneously the underestimate at great magnitude is reduced.