Real-time earthquake magnitude estimation method for earthquake early warning system

Abstract

The invention discloses a real-time earthquake magnitude estimation method for an earthquake early warning system. The moment magnitude is solved via earthquake moments, namely, a corresponding moment magnitude is calculated every second after that a signal is detected, and an estimated magnitude very approximate to the practical magnitude is obtained about 20s. The moment magnitude is obtained from the earthquake moments to overcome the problem of magnitude saturation in great earthquake (M>6), the earthquake moments have clear connection with the amplitude omega0 in zero frequency, and the physical meaning is clear. The method of the invention is in real-time, the corresponding moment magnitude is calculated every second after that the signal is detected, the estimated magnitude very approximate to the practical magnitude is obtained about 20s, and the method can be effectively applied to the earthquake early-warning system.

Description

technical field [0001] The invention relates to a novel earthquake magnitude estimation method used in an earthquake early warning system, in particular to a spectrum inversion method for overcoming the magnitude saturation problem of medium and large earthquakes and estimating real-time magnitude. Background technique [0002] In recent years, large [0003] Earthquakes are becoming more and more frequent, and may even cause secondary disasters such as tsunamis, landslides, collapses, and ground fissures. In our country, there have been many destructive earthquakes in history, especially the Sichuan earthquake in 2008. It can be seen that earthquake disasters have caused a great threat to people's life and property safety. [0004] The earthquake early warning system refers to the use of the characteristics that the propagation speed of seismic waves is lower than that of radio waves after an earthquake, and early warning of places where seismic waves have not yet arrived....

AI Technical Summary

Problems solved by technology

Therefore, it is determined that the seismometers corresponding to the above magnitudes can only reflect earthquakes within a certain frequency range, and outside this range, due to the limitation of instrument performance, it is impossible to measure seismic waves with a period greater than 20s radiated when an earthquake occurs (especially for large magnitude 7.0 After the surface wave magnitude), the determined magnitude cannot reflect the actual magnitude of the earthquake, that is, the phenomenon of "magnitude saturation" appears

[0007] (2) The physical meaning is not clear

The current magnitude estimation method is only determined by the amplitude of the instrument's pointer swing, which has no clear physical meaning and cannot profoundly reveal the relationship between earthquake magnitude and frequency

[0008] (3) Not real-time

The currently used magnitude estimation method takes a long time. It usually takes 1-3 minutes to get the magnitude accurately for an earthquake analysis, which cannot be practically applied to the earthquake early warning system.

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