Seismic response analysis of Qom sedimentary basin using Spectral Element Method in time and frequency domain

In recent decades, the importance of the geological features of the site on the severity and extent of damages has become apparent in many seismic events. How these properties relate to the amplitude and the frequency content of the movements is studied as the title of site seismic response. In the present study, the seismic response of a two-dimensional section of sediments located in the eastern part of the sedimentary basin Qom city has been investigated. For this purpose, numerical modeling has been performed using Spectral Element Method in time domain and the results also studied and presented in frequency domain by applying Fourier transform. The results in the time domain show that the largest amplitudes of movements can be observed in the southeastern parts of the urban area. These findings are in agreement with previous studies. Also, it is revealed that the main reason for increase of the duration of the movements in the basin is the surface waves originating from the edges of the basin. The results in the frequency domain indicate that the most important amplifications in the basin can be seen from about 0.8 Hz for the southern parts of the profile to about 2 Hz for the northern parts. This amplification range also agrees with previous observations.