Kirchhoff型真振幅偏移与反偏移

对Kirchhoff型真振幅偏移和反偏移理论中的基本概念、基本假设和基本公式进行了简要的回顾和综合评述，并探讨了在今后发展中所面临的问题。从研究问题的出发点来看，已发表的真振幅成像理论与波动方程没有直接的关系。在数学上，加权绕射叠加和等时线叠加的表达方式具有多样性，真振幅加权函数具有多解性,这为真振幅偏移和反偏移的实现提供了多个途径。如果速度模型过于复杂，已发表的真振幅加权函数将在波场的焦散区失效。因此，在今后的研究中要探讨焦散区的加权函数计算问题。此外，要找寻最佳偏移孔径的快速估算方法，建立相应的预处理体系，并将现有的标量理论推广到矢量波场和各向异性介质。

Kirchhoff type true amplitude migration and demigration

I briefly review the basic concepts and assumptions as well as the basic equations in Kirchhoff-type migration and demigration. It is found that the starting point of the true-amplitude imaging theory has no direct relation to the wave equation, and that both of the diffraction- and the isochrone-stack can be formulated in different forms. Further, the true-amplitude weight function has no unique solution. This gives a possibility to implement the true-amplitude imaging in different ways. If the macro-velocity model is too complicated, the published weight functions become invalid in caustic regions. Therefore, a key point for further research is to find the weight function valid in caustic points. Furthermore, it is necessary to find a method for fast estimation of the optimal aperture, and to extend the present theory from scalar wave-field to the vector one, and from the isotropic media to the anisotropic media.