基于波场延拓的反Q滤波方法比较

摘要

Wavefield continuation algorithm is the most common inverse Q filtering method;nevertheless,due to the unstability of ampli-tude factor,part of the high frequency is magnified,which affects the results of inverse Q filtering.It is thus confirmed that complete sta-bility amplitude compensation is only related to Glim by formula derivation,which causes difficulty to improve deep seismic wave resolu-tion.The authors systematically analyzed the filter properties of different amplitude compensation operators in the wavefield continuation inverse Q filtering.Gain control compensation method is neither magnify nor suppress a certain frequency.Regularized and iterative com-pensation methods not only have strong anti-noise capability but also have better amplitude compensation capability for deep seismic waves.By applying different amplitude compensation operators to theoretical models and actual data of cross-well seismic data,the au-thors found that regularized and iterative amplitude compensation factors have strong suppression effects on high-frequency interference;for middle and deep part of seismic records and seismic records with low-Q energy attenuation,they also have better compensation effects.%波场延拓法是最常用的反Q滤波方法,但其振幅因子的不稳定性致使深层的高频信息放大,从而影响反Q滤波的效果.本文通过推导证明了完全稳定振幅补偿只和Glim(增益限制)有关难以提高深层地震波分辨率,系统分析了波场延拓反Q滤波算法中不同振幅补偿算子的滤波特性,增益控制法对某一频率之后既不放大也不压制,正则化滤波和迭代滤波法不仅具有较强的抗噪声干扰能力,而且对深层地震波具有较好的振幅补偿能力.通过对理论模型和井间地震实际资料应用不同振幅补偿算子,发现正则化振幅补偿因子和迭代法振幅补偿因子不仅对高频干扰有较强的压制效果,而且对于地震记录的中深层部分和低Q能量衰减严重的地震记录,都有较好的补偿效果.