相位校正S域反褶积方法及应用

Deconvolution in S domain with phase correction and its application

反Q滤波和时频(S)域反褶积都可以提高衰减地震记录的分辨率。通常指数增益导致反Q过程不稳定;而时频域反褶积虽然可以很好地适应地震记录的非平稳性,但只能去除子波振幅谱的影响,无法准确提取子波相位谱,从而影响反褶积结果。为此,引入反Q滤波的相位校正方法,使衰减地震记录零相位化,优化反褶积的基础条件;再通过改进的广义S变换在S域实现反褶积,达到高分辨处理的目的。模型数据测试和辽西实际数据应用的结果均表明,相位校正S域反褶积能得到更准确的结果,是识别薄互层和刻画地层尖灭点的有效方法。

Inverse Q-filter and time-frequency domain deconvolution can improve the resolution of attenuated traces.However,coefficient gain causes inverse Q-filter very instable,and how to accurately estimate Q value is another key issue.Time-frequency domain deconvolution can well adapt to instable seismic records.However,due to the phase distortion of seismic wavelets during the propagating process,time-frequency domain deconvolution can only remove the influence of wavelet amplitude spectra,but cannot accurately extract wavelet phase spectra,affecting the deconvolution result.We propose to optimize the basic conditions of deconvolution by correcting the phase of attenuated seismic records,and then we can achieve deconvolution in S domain through improved genera-lized S transform.Applications to model and actual seismic data have proved that phase-corrected S-domain deconvolution can get more accurate results,and it is an effective method to identify thin layers and describe stratigraphic pinch-out points.