几种反射波时距方程的比较

Comparison on several time-distance equations of reflecion wave

在地震资料处理中,速度分析和成像技术极为重要.常规地震资料处理方法是利用双曲线方程来描述反射波时距曲线规律,此方程随着地层非均质性、各向异性和排列长度的增加,其误差变大.目前发展的反射波非双曲时距方程,主要有基于层状各向同性模型的非双曲时距方程、基于均匀弱各向异性模型的时距方程、基于速度随炮检距变化模型的时距方程、基于线性连续速度模型的时距方程.本文针对三个典型的模型:层状均匀各向同性模型、层状弱各向异性模型和层状非均匀模型,对这几种时距方程进行了精度比较与分析,得出了一些有益的结论.最后,从不同角度说明了应用这几种方程的合理性.

Velocity analysis and imaging are very important in seismic data processing. Conventional seismic data processing method uses hyperbolic equation to describe time-distance formula of reflection wave, error of this equation increases with the increase of heterogeneity, anisotropy and spread length. Currently developed nonhyperbolic time-distance equations are mainly based on horizontally layered isotropic model, weakly anisotropic model, velocity varying with offset model, linear continuous velocity model respectively. Accuracies of these time-distance equations are compared on the following three models： horizontally layered isotropic model, weakly anisotropic model and horizontally layered heterogeneous model, some useful conclusions are drawn, Finally, rationality of adopting these equations is illuminated from various aspects.