叠前地震资料提高分辨率处理方法及应用

Methods and applications for improving pre-stack seismic data resolution

对于隐蔽性油气藏和复杂构造油气藏,地震反射资料难以满足精度要求,需要开展地震资料提高分辨率处理.为此,使用反Q滤波、广义S变换、谱整形技术及谱白化技术等方法处理了涠西南地区叠前地震资料,并且分析了四种提高分辨率方法的应用效果.结果表明,四种方法都能提高主频、拓宽频带,其中反Q滤波的效果最好,广义S变换效果次之.反Q滤波结果中波组的低频和中高频能量分配合理,并且在中高频段反Q滤波结果的信噪比明显高于其它三种方法.此外,使用不同Q值对反Q滤波结果影响比较大.随着Q值增加,主频和带宽都稍有降低的趋势,但是信噪比提高了.当Q值大于200.0时信噪比改善的空间已经很小,这时再提高Q值,换来的只是主频降低和带宽缩小.

The precision of seismic reflection data does not fulfil to explore private and complex structure oil gas accumulations. So we need to improve the resolution of the seismic data. To achieve this, we processed the prestack seismic data in Weixinan using four methods of improving the resolution, namely the inverse 0 filter, the generalized S transform, the spectrum anaplasty and the spectrum whitening. We compare the processing results for four methods. The results indicated that those methods can improve peak frequency and frequency bandwidth, where the result for the inverse Q filter is best and the result for the generalized S transform takes second place. Low and middle-high frequency components are reasonable in the result for the inverse Q filter, and its signal/noise ratios are obviously larger than that for other methods in middle-high frequency. Moreover, the results using various Q values indicated that the peak frequency and the frequency bandwidth are little reduced when Q value is increasing, but the signal/noise ratio is increasing. The signal/noise ratio is not obviously improved very small when Q value is larger than 200.0. Then we only gain reducing of the peak frequency and the bandwidth adding Q value again.