Influence of the finite fault location on the three-dimensional basin seismic effect

The earthquake caused by underneath faults often causes serious damage to the cities above the basin. In this paper, by comparing the distribution characteristics of ground motion intensity and amplification factor between the basin model and the one-dimensional horizontal layered model, the influence of the fault location （FL） on the basin seismic effect is investigated in detail. The results show that the FL has significant influence on the strong motion inside the basin. The basin edge effect is more significant when the fault is close to and parallel to the basin boundary, and the locations of the strongest ground motion regions change with the FL. The amplification factor （AF） exhitbits different distribution characteristics for three components. The main amplification regions of the fault-parallel and vertical components generally locate on both sides of the fault trace or near the basin edge close to it, while the main amplification regions for the fault-normal component locate inside the basin, which also displays the smallest AF. Both the strong motion and AF show greatest values when the fault just beneath the basin short-side edge, which is the most hazardous case.