EARTHQUAKE OBSERVATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To obtain accurate earthquake information from an earthquake observation system by remarkably improving the accuracy of the system when the system detects the first arrival time of P-waves and S-waves by improving the S/N by making the difference between normal noise and seismic waves definite. SOLUTION: An earthquake observation system fetches the waveform signals of an earthquake outputted from seismometers and calculates the first arrival time of P-waves and S-waves by a statistic method using an autoregressive model. When the evaluated values of the first arrival time of the P- and S-waves are lower than preset reference values, the system recalculates the first arrival time of the P- and S-waves by using the statistic method using the autoregressive model after performing filtering using wavelet transformation on the waveform signals of the earthquake outputted from the seismometers by means of a signal processor 7 and calculates hypocenter information based on the recalculated first arrival time.