Synthetic seismograms of ground motion near earthquake fault using simulated Green’s function method

Seismograms near source fault were synthesized using the hybrid empirical Green＇s function method where the discretely simulated seismic waveforms are used for Green＇s functions instead of the observed waveforms of small earthquakes. The Green＇s function seismic waveforms for small earthquake were calculated by solving wave equation using the pseudo-spectral method with the staggered grid real FFT strategy under a detailed 2-D velocity structure in Kobe region. Magnitude and seismic moment of simulated Green＇s function waveforms were firstly determined by using the relationship between fault length and corner frequency of source spectrum. The simulated Green＇s function waveforms were employed to synthesize seismograms of strong ground motion near the earthquake fault. The synthetic seismograms of the target earthquake were performed based on the model with multiple source rupture processes. The results suggest that synthesized seismograms coincide well with observed seismic waveforms of the 1995 Hyogo-ken Nanbu earthquake. The simulated Green＇s function method is very useful for prediction of the strong ground motion in region without observed seismic waveforms. The present technique spreads application field of the empirical Green＇s function method.

Synthetic seismograms of ground motion near earthquake fault using simulated Green’s function method

Seismograms near source fault were synthesized using the hybrid empirical Green’s function method where the discretely simulated seismic waveforms are used for Green’s functions instead of the observed waveforms of small earthquakes. The Green’s function seismic waveforms for small earthquake were calculated by solving wave equation using the pseudo-spectral method with the staggered grid real FFT strategy under a detailed 2-D velocity structure in Kobe region. Magnitude and seismic moment of simulated Green’s function waveforms were firstly determined by using the relationship between fault length and corner frequency of source spectrum. The simulated Green’s function waveforms were employed to synthesize seismograms of strong ground motion near the earthquake fault. The synthetic seismograms of the target earthquake were performed based on the model with multiple source rupture processes. The results suggest that synthesized seismograms coincide well with observed seismic waveforms of the 1995 Hyogo-ken Nanbu earthquake. The simulated Green’s function method is very useful for prediction of the strong ground motion in region without observed seismic waveforms. The present technique spreads application field of the empirical Green’s function method.