Abstract：Dual-variable grid algorithm can be applied on fine simulation of wave fields of complex reservoirs with high calculation efficiency.However,with the variable space grid and variable time step,numerical noises would be generated at the interface of different grids and steps.In order to obtain more accurate numerical modeling results on locally complex structures,quantitative studies and comparisons on varying-space grids with interpolation method and variable coefficient method are implemented by theoretical analysis and numerical stimulation experiments.An error analysis of locally variable time step method is also conducted in this paper.Errors generated by each of the three methods mentioned above are then quantitatively studied to determine the application scope of each corresponding method.And thus the simulation accuracy can be guaranteed in case of weak anomaly of wave field by choosing appropriate method and parameters.
