INFLUENCE OF ASPERITY PARAMETERS ON THE FOURIER SPECTRUM

摘要

Brune's model is used for predicting the Fourier spectrum of single asperity. In order to discover the influence of the asperity parameters on the ground motion, the asperity is simulated in the different conditions, which include the area and the stress drop of the asperity. The simulation result shows that the stress drop and the asperity area play important role in the far field Fourier spectrum. However, the research results also show that these source parameters have different influences on the Fourier spectrum at different frequencies. The asperity area has great influences on spectrum in low frequency range than in high frequency range. And, when the asperity area is invariant the Fourier amplitude spectra increased obviously with the increase of stress drop on the single asperity. And the shapes of spectrum in different stress drops are approximately the same in all frequencies.