基于波场延拓的多次波压制技术及其改进

水层多次波是海上地震勘探过程中的一个重要干扰因素。为压制水层多次波,本文在倾斜模型条件下采用基本的正向延拓方法去除多次波,取得了较好的压制效果。在此基础上实现了弯曲水底情况下正、反向波场延拓方法压制多次波;经对比发现,反向延拓方法克服了复杂水下介质情况下对格林函数求取的干扰,消除多次波效果更好。

Method of wave field extrapolation and its improvement to remove multiples

Suppression of water multiples is an important factor in the process of seismic exploration． To sup- press water multiples，this paper first realizes the basic field forward extrapolation method for removing multiples in the case of gradient model and achieves good multiples removal efficiency． Then，on the basis of forward extrapola- tion，we realize inversed and forward wave field exploration method in the case of bending bottom． Comparing the results of the two field extrapolation of suppressing water multiples，we find that this reversed wave field extrapola- tion can overcome the interference of the complex underwater conditions when obtaining the green function，and obtain more preferable effect of multiples elimination in the case of complex underwater medium．