基于频率拓展的表面多次波压制方法

Surface multiple attenuation method based on the frequency extension

为消除多次波预测中多余的子波效应,拓宽地震数据的频带,使预测多次波的走时、振幅和相位与实际的多次波相吻合,根据原始数据,衍生频率拓展道等多道地震数据;根据最小二乘原则,得到自适应滤波器和压制多次波后的有效波数据。结果表明:基于频率拓展的多次波压制方法,能够有效压制多次波,提高地震资料的信噪比;对水平层状模型测试结果频谱分析,自适应相减后得到的有效波同预测的多次波相比,频带拓宽,高频能量增强;通过对SMAART模型测试,基于频率拓展的多次波压制方法在噪声较强的情况下,也能得到很好的多次波压制效果。对于地质结构较复杂的情况,与抛物Radon变换滤波法相比,该方法多次波压制效果更好,并且不损害有效波能量。

In order to eliminate the extra wavelet effects in the multiple prediction,widening the frequency band of the seismic data,the predicted multiples of the forecast coincide with the real multiples of travel time,amplitude and phase.Based on the original data,this method derives multi-channel seismic data such as frequency extension channel.Based on the principle of least squares,an adaptive filter is obtained,and the primaries obtained after suppression of multiples.The surface multiple attenuation method based on frequency expansion can suppress the multiples,and improve signal-to-noise ratio of seismic data.Spectrum analysis of the horizontal stratified model shows that the frequency band obtained of the primaries after the adaptive subtraction is wider than the frequency band of the multiples and the high-frequency energy is enhanced.Through the SMAART model test,the multiple attenuation method based on frequency expansion can get multiples suppression effectively under strong noise conditions.In the case of complex geological structure,this method can get the better multiples suppression effect than parabolic Radon transform filter method,without damaging the effective wave energy.