具有剔除噪音功能的多道广义线性反演

Generalized multi-traces linear inversion with the removal of noise

北京石油勘探开发科学研究院地球物理所, 北京100083

Petroleum Geophysics Institute Beijing 100083

常见的各种基于单道的叠后地震道波阻抗反演技术,尽管其抗噪能力不尽相同,但都不能完全消除噪音对反演结果的影响。本文利用了广义线性反演算法本身具有的特点,注意到在实际记录与模型合成记录的残差剖面上,信号和噪音存在的差异,残差相干部分反映有效信号,随机部分为噪音。运用多道记录同时进行波阻抗反演,在选代过程中将残差的相干部分用于波阻抗修正量的计算,从而避免了噪音参与波阻抗变化量的计算。根据残差是否为随机噪音提出一种检测噪音的迭代终止准则,实现了在反演波阴抗的同时剔除噪音、理论模型和实际资料反演说明本文提出的方法是稳健的,应用效果良好。

Based on single trace, the convcntional technigucs for calculating acoustic impodancc by theinversion of post-stack seismic traces can’ t completely removc noise effect from invcrsion results ;though they have different abilities to suppress noise. By using GLI’S algorithmie advantages onecan notice the differcnce between signal and noise in the residual crror section, the coherentcomponents and the random components in the residual error section represent signals and noisesrespectively. Through the inversion of acoustic impedance by using multi-traces recordsimultaneously, the coherent components are utilized only in the computation of wave impedancemodification during the process of iteration with the excluding of noises. According to whetherrcsidual crror is a random noise we present a criterion of iterative termination which has the function of noise detecting, and so noise can be removed while impodancc inversion beingperformed. The synthetic and real data invetsion shows that our method is robust with which wecan obtain satis factory results.