CDP道集地震反射波特征描述及特征提取方法

Description and extraction of seismic reflection wave characters in CDP gather.

建立了包含AVO和PVO影响的CDP反射波道集模型 ,并给出了子波、AVO、PVO和信噪比估计的方法。当CDP反射道集仅存在AVO影响时 ,可采用时间域叠加法或奇异值分解法估计子波、AVO和信噪比 ,振幅极性的反转会影响时间域叠加法的效果 ,但不会影响时间域奇异值分解法的效果 ;当CDP反射道集存在AVO和PVO影响时 ,可采用频率域叠加法或奇异值分解法估计子波、AVO、PVO和信噪比 ,振幅和相位的变化特征会影响到频率域叠加法的效果 ,但不会影响频率域奇异值分解法的效果。文中对 4种方法进行了比较 ,频率域奇异值分解法是最为有效的方法。

The CDP reflection gather model considering AVO and PVO effects is constructed, and the method of estimating wavelet, AVO, PVO, and S/N ratio are given. When CDP reflection gather includes only AVO effect, estimation of wavelet, AVO, and S/N ratio can be made by time domain stacking or singular value decomposition (SVD). The ampitude polarity reversal will affect the result of time domain stacking, but not affect that of time domain SVD. When CDP reflection gather includes AVO and PVO effects, wavelet, AVO, PVO, and S/N ratio can be estimated by frequency domain stacking or SVD. The change of amplitude and phase will affect the result of frequency domain stacking, but not that of frequency domain SVD. The comparison of these four methods shows that the frequency domain SVD method is the most effective.