小波变换在波阻抗反演中的应用

Inversion of Acoustic Impedance by Wavelet Transform

介绍了利用小波变换进行多道波阻抗反演的原理．鉴于地震剖面上不同的频带有不同的信噪比，以及相邻地震道的反射波有效成分在波形和能量上有较强的相关性，笔者结合小波变换的特点，运用多道记录同时进行波阻抗反演，即在迭代过程中将实际记录与模型合成记录的残差道进行小波分解，形成残差道分频小波剖面，然后利用Ｋ－Ｌ变换提取分频剖面中的相干部分用于波阻抗变化量的计算，从而避免了噪音参与波阻抗变化量的计算．展示了理论模型与实际应用的例子，说明该反演方法稳定性强。

The principle is introduced of the inversion of multitrace acoustic impedance by wavelet transform.The inversion of acoustic impedance can be finished by using multitrace records because the different frequency band has different signal/noise ratio in a seismic section and there is a good correlativity of the waveform to the energy of the effective waves of neighboring seismic traces.The residual error of signal and noise is decomposed by wavelet transform in the process of iteration,and the seismic sections with different frequencies can be get.The coherent component of the seismic sections is extracted by KL transform to be used for the computation of the modification of acoustic impedance,so noise can be removed from the computation.Theoretical model and practical examples show that this method has good stability and wide applications.