广义S变换与二维离散小波变换联合压制面波

摘要

Surface waves are the main factors affecting the signal to noise ratio (SNR) in prestack seismic records.A surface wave suppression method using generalized S-transform and 2D discrete wavelet transform is proposed.Firstly,the surface wave is separated from the seismic records by a generalized S-transform.Then,to reduce the damage to effective low-frequency waves owing to separation,the separated surface waves are decomposed further using 2D discrete wavelet transform to obtain four wavelet coefficient components.Subsequently,high-pass filtering is performed on the low-frequency high-wavenumber component containing the surface wave to filter out the surface waves.Next,the filtered wavelet coefficient components are reconstructed and then stacked into the separated seismic records without the surface wave to realize surface wave suppression.Testing on both synthetic data and field data shows the proposed method can effectively suppress and improve the SNR of seismic records.%地震记录中的面波是影响地震资料品质的主要因素之一,传统的面波压制方法有其固有缺陷.提出了一种新的广义S变换与二维离散小波变换联合的面波压制方法.首先利用广义S变换分离原始地震记录中的面波,为减少分离过程可能对低频有效反射波造成的损伤,将分离出来的面波记录再次进行二维离散小波分解,得到4个小波系数分量,然后对包含面波成分的低频高波数分量进行高通滤波,滤除面波,保留有效反射波,最后进行小波系数分量重构,将滤除了面波成分的重构结果叠加到已分离面波的地震记录中,实现对面波干扰的联合压制.理论模型试算和实际资料应用表明,广义S变换与二维离散小波变换联合的面波压制方法能够在有效压制面波干扰的同时,减少对有效反射波的损害,提高了地震资料的信噪比.