Three methods of wave equation forward modeling and comparisons
波动方程数值模拟的三种方法及对比

Wave equation forward modeling is a very important way to study the seismic propagation underground. In this paper, seismic forward modeling based on two-way acoustic wave equation and two-way elastic wave equation is done using the staggered-grid high-order difference method. Besides, according to the positioning principle, simulation based on one-way acoustic wave equation is made by the Fourier finite difference propagator. In the progress of computing, each geophone directly receives the wave field that has been extrapolated to the surface of the model without lateral stacking. The three simulation results show that two-way wave equations generate directive wave and multiple wave which reduce the SNR severely, while the one-way wave equation method gives a higher SNR with only reflected wave, but it creates larger errors with wide-angle incident wave. For the same model, two-way elastic wave equation algorithm costs the most computational time, one-way acoustic wave equation algorithm costs the least and two-way acoustic wave equation algorithm in between. So for a complex structure model, the three modeling methods can be used simultaneously with different advantages and disadvantages.