测井约束地震子波外推方法研究

Seismic wavelet extrapolation with constraint of log data

地震子波的提取是波阻抗反演及正演模拟的基础。本文首先研究了确定性子波提取方法所存在的问题，如子波长度的确定、截断误差的影响、直流分量的消除及随机噪声的影响等；然后对近期发展起来的利用地震记录的高阶累积量估算地震子波的方法进行了理论分析；进而将上述确定性方法和统计性方法结合起来，研制出了一种测井约束外推地震子波的新方法；最后对实际资料进行了试界，其结果表明，利用测井约束的子波外推方法获得的子波比传统方法要精确。

The extract of seismic wavelet is the base of wave impedance inversion and forward modeling. Some matters involved in extracting deterministic wavelet are discussed, which are the determination of wavelet length, effect of truncation error,the elimination of direct current component, random noise effect and so on. Then,a recent method for seismic wavelet estimation using a high-order cumulant of seismic data is analysed theoretically in detail. Combining deterministic method withstatistical method forms a new method for seismic wavelet extrapolation with constraint of log (lata. The trial result of real dilta shows that the seismic wavelers obtained with this new method are better than those produced with ordinary methods.