多次波问题的研究进展

Progress on the multiple problems

综述了当前多次波问题的研究进展,指出了对多次波问题,有两种主要的处理思路:(1)因为后续偏移成像的需要,把多次波看成相干噪声,根据多次波特性设计衰减方法将其消除掉,将其称之为多次波衰减方法.多次波衰减方法大体上可以分为两类:基于信号分析的滤波方法和基于波动方程的预测相减法.预测相减法不需要或较少需要有关地下的先验或后验信息,能适应复杂地下构造.本文对预测相减法中的波场延拓法、反馈迭代法、逆散射级数法和恒定内插法等三种主要方法,进行了较详细的对比分析和介绍.(2)将多次波看成有效信号,对其成像,将其称之为多次波成像方法.这种方法提取了多次波中包含的地下界面信息,可改善地震资料的成像质量.

This paper reviews the recent reseach progress of multiple problems and points out there are two main ways to deal with the multiple problems. The first way is called as the multiple elimination method. In this way the multiples are considered as coherent noise because of the need of migration and the multiple elimination methods are designed to remove the multiple according to the characteristics of the multiple. The elimination method could be classified as the filter method and the prediction method. The filter method is based on the signal processing. The prediction method is based on the wave equation. It don＇t need, or rarely need the a priori or posteriori information about the underground structure, so it could be suitable for the complicated underground structure. To the wavefield extrapolation method, the feedback method, the inverse-scattering series method and the invariant embeding methed of the prediction method, this paper gives the detailed contrastive analysis and introduction. Another way could be called as the multiple imaging method. In this way the multiples are regarded as the valid signal and imaged. This method picks up the underground information in the multiples, so it can improve the imaging quality of the seismic records.