基于形态分量分析的保幅面波压制方法

根据近年来发展起来的稀疏信号理论及有效反射波与面波的形态特征不同,将含面波炮记录单道化,采用形态分量分析(MCA)方法分离面波。MCA方法的核心是选取适当的字典,从有效反射波与面波的形态差异出发,选取-维非抽样离散小波波变换(UDWT)字典和局部离散余弦变换(LDCT)字典,-维UDWT字典用来稀疏表示面波部分,-维LDCT字典用来稀疏表示有效反射波部分。采用块协调松弛算法(BCR)求解目标函数,将单道化的含面波单炮记录分为有效反射波部分和面波部分,进而达到去除面波的目的。实际资料处理表明,利用本文MCA方法能够有效压制面波,同时能较好地保护有效反射波(特别是反射波的低频、低波数成分),是-种保幅的面波压制方法。

Amplitude-preserved ground-roll suppression method based on morphological component analysis

A ccording to the recently developed sparsesignal theory and the morphological differences be-tween reflections and ground-roll，the shot gatherwhich contains ground-roll is reshaped to be a one-dimensional array，and the morphological compo-nent analysis(MCA) technique is used to separatethe ground-roll.The key of the MCA method is tochoose the appropriate dictionaries.In view of themorphological differences between reflections andground-roll，two kinds of dictionaries are chosen.They are the one-dimensional UDWT dictionaryand the one-dimensional LDCT dictionary.Thefirst one represents sparsely the ground-roll com-ponent in common-shot records，and the secondone represents sparsely the reflections in common-shot records.Block-coordinate relaxation(BCR)algorithm is used to calculate the objective func-tion，and the shot record is decomposed intoground-roll component and reflection component.Then the ground-roll is removed.Real data exam-ples show that the MCA method not only can suc-cessfullv remove ground-roll，but also preserve re-Elections，especially for low frequency and lowwave-number information.