中文摘要：

针对复杂山地开展多波地震勘探时,合理的观测系统设计是获取有效资料的关键因素,如何利用数值模拟方法建立更为准确的观测模型,也成为亟待解决的问题。模拟过程中首先采用中心差商逼近波动方程中的偏导数,建立多波（纵波和转换波）波动方程的显式差分格式。其次,以SPML（分裂式完全匹配）方法和NPML（非分裂式完全匹配）方法为基础,设计一种高效的PML改进算法来消除起伏地表的边界影响。最后,以Marmousi模型为基础建立复杂山地地形的理论模型,得到地震波场数值模拟结果。利用所提出的算法对该模型进行波场分离,分离的最终效果很好地验证了这一算法的可行性。

英文摘要：

To implement multi-wave seismic exploration in complex mountainous area,it＇s important that design a reasonable observation system to obtain valid data,and it has become a serious problem that how to establish a more accurate measurement model using numerical simulation. To establish the simulation process,firstly,a multiwave（ P-wave and converted wave） wave equation of explicit difference scheme is built, which uses the approximating partial derivative of the wave equation with the center difference quotient. Secondly,a high efficient PML algorithm to eliminate the boundary of the irregular surface effects is put forward based on the SPML（ splitting perfect matched layer） method and the NPML（ non-splitting perfect matched layer） method. Finally, the theoretical model of complex mountainous terrain is established using the Marmousi model. The wave field separation for the model is implemented using the presented algorithm in this paper,the feasibility of this algorithm is verified trustworthy with the separation result.