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面波是地震记录上严重的干扰波。基于小波变换的面波衰减方法考虑了面波频率低的特点,但是当有效信号和面波干扰存在频率重叠时,其压制效果不理想。径向道变换考虑了面波与有效信号视速度差异,有利于去噪,但是在去除面波的同时也会损害有效信号的低频分量。本文根据面波和有效信号在视速度以及小波域能量的差别,将小波变换的局部分析能力与径向道变换的去噪优势相结合,提出了基于小波分频与径向道变换的联合面波压制方法。首先应用小波变换,将地震记录分解为不同频段,对出现面波的频段作径向道变换,然后再作低切滤波处理,最后利用径向道反变换后的记录与其他频段的记录进行小波重构得到去除面波的记录。两种方法的联合使用提高了小波分频去除面波的能力,同时也较好的保护了有效信号。通过模型数据实验分析和实际资料数据处理的结果表明,本文提出的方法具有较强的去噪能力和良好的保幅性能。
Surface waves are serious interference waves on seismic records. The surface wave attenuation method based on wavelet transform considers the low frequency of surface wave, but its suppression effect is not ideal when there is frequency overlap between effective signal and surface wave interference. The radial tract transform takes into account the difference between the apparent velocity and the apparent velocity of the effective signal, which is good for denoising. However, removing the surface wave will also damage the low frequency component of the effective signal. Based on the difference between the apparent velocity and the energy of the wavelet domain, the local analysis ability of wavelet transform is combined with the denoising advantage of radial tract transform. Based on wavelet transform and radial tract transform, the joint face Wave suppression method. Firstly, the wavelet transform is used to decompose the seismic records into different frequency bands, and then the radial bands are transformed to the frequency bands where the surface waves appear. Then the signals are processed with low-cut filtering. Finally, the records after inverse radial transformation are compared with the records of other frequency bands. Reconstruction to get the record of removing surface waves. The combined use of the two methods improves the ability of the wavelet divider to remove surface waves and at the same time better protects the effective signal. The experimental results of model data analysis and actual data processing show that the proposed method has strong denoising ability and good amplitude preserving performance.