Abstract: Aiming at the complex geological structures with the topographic relief, complex surface structures and strong velocity contrast in the mountain front area in Xinjiang, the first-arrival waveform inversion is adopted for detailed modeling of surface velocity. The results show that first-arrival waveform inversion can be used to reconstruct the fine details of the surface velocity model. Time-domain waveform inversion is somewhat sensitive to the initial model. The forward modeling indicates that seismic wave propagation is severely affected by the surface structure. The modeling precision, lateral resolution and illumination could be influenced by the irregular topography model with large dip and strong velocity contrast, hence leading to lower degrees of the modeling precision and resolution.

Key words: irregular surface, velocity modeling, first-arrival, waveform inversion, objective function