基于地震子波支撑和Curvelet域稀疏约束的面波衰减方法

面波噪声衰减是地震数据处理流程中的重要一环,传统的面波衰减方法主要依靠面波与有效信号的几何特征差异,在变换域中将两者进行分离.受复杂近地表因素的影响,面波往往呈现非线性特征,并且在变换域中面波与有效信号存在部分重叠,这都导致面波噪声与有效信号难以彻底分离,消除面波的同时也损伤了有效信号.针对这一问题,本文综合利用Curvelet变换对地震数据的稀疏表征特性以及地震子波支撑来构建方程,通过Curvelet域稀疏约束来恢复压制面波时损失掉的有效信号.文中对该方法进行了模型试算和实际资料处理,处理结果表明:本文方法能够在一定程度上恢复损失的有效信号,提高了面波压制方法的保幅性.

Ground-roll attenuation method based on the seismic wavelet supported and sparse constraint in Curvelet domain

Ground-roll attenuation plays an important role in seismic data processing,the traditional methods mainly use the differences between ground-roll and signal in geometric characteristic to separate them in transform domain.Affected by complex near-surface structure factor,the ground-roll is often nonlinear and partly overlap with signal in the transform domain,which makes it difficult to completely separate the ground-roll from the seismic records.When the ground roll is completely eliminated,the signal is also damaged.To solve this problem,a new method is proposed in this paper.We utilize the sparsity of seismic records in the curvelet domain and the support of seismic wavelet to construct equation,and the lost signal during the suppression of the groundroll is recovered by sparse constraint in Curvelet domain.The model and field data are used to test the proposed method,the results show that the proposed method can recover the loss signal during groundroll suppression processing and improve the amplitude-preservation characteristic of ground-roll attenuation method.