广义屏深度偏移方法的应用效果分析

为了解决复杂介质条件下的成像问题，从原理上简要介绍了近年来广受地球物理学界关注的广义屏深度偏移方法。方法是基于波的散射理论并借助于局部Born近似导出，是在空间域和波数域交替进行波场管延拓的双域偏移方法，具有较高的计算效率1。广义屏深度偏移算子能适应速度场较强的横向变化，并能保证对陡倾地层的精确成像。数值试验中，强横向变速理论模型合成数据及实际资料的叠后深度偏移结果都表明，广义屏算子在复杂地质成像方面具有较大的应用价值。

Generalized screen depth migration method and its application

To solve the imaging problems in complicated media, the author briefly discusses the principle of generalized screen migration, which is paid close attention recently in the circle of geophysicists. Based on the theory of scattering wave, this method is deduced by means of local Born approximation. It is implemented in dual (space and wavenumber) domain with high efficiency. Moreover, the generalized screen operator works in media with laterally varied velocity, and can image reflectors with steep dip accurately. Poststack depth migration results from numerical tests of synthetic data with strong varied velocity and field data show that the generalized screen operator has great application value in imaging the complex geological bodies.