基于迭代反演的层间多次波压制方法

Internal multiple suppression method based on iterative inversion

层间多次波与有效波在走时、频率和叠加速度上差异较小,因此层间多次波压制常难以获得理想效果.本文提出一种基于迭代反演的层间多次波压制方法(MSI,Multiple Suppression Inversion),该方法以共聚焦点(CFP,Common Focus Point)层间多次波压制理论为基础,通过构建卷积因子,将层间多次波压制转变为迭代反演的问题,直接利用观测的地震数据进行迭代反演计算,进而完成多次波压制.MSI方法避免了共聚焦点方法中构建CFP道集的聚焦运算,大幅降低层间多次波预测的计算成本;同时该方法为全数据驱动方法,无需地下介质任何先验信息,算法容易实现.模型数据测试表明,本文提出的方法可有效压制层间多次波,而且对有效波也具有很好的保幅性.

The suppression of internal multiples is a difficult problem in seismic data processing,especially for the processing of field data.In general,there is no obvious difference in time,frequency and stacking velocity between internal multiples and primaries,which is a great challenge in the identification,prediction and suppression of internal multiples.In this paper,we propose a convolution factor based on the theory of Common Focus Point(CFP)internal multiples suppression,which makes the suppression of internal multiples become an iterative inversion process to suppress internal multiples.Multiple Suppression Inversion(MSI)avoids the focusing operation which requires to construct the CFP gathers,so that the computational efficiency of multiples prediction is greatly improved,without the need for any prior information in the subsurface,which is fully data-driven.Tests on model data proves that the method proposed in this paper is effective and feasible.