Conclusions

Velocity-independent Stolt residual migration improves the image focusing for a model with significance for seismic imaging problems in areas of large velocity contrast and limited illumination. In this study I have found that residual migration is applicable and can generate better-focused images. The entire process is cheap, with a cost comparable with that of a suite of Stolt migrations.

The potential pitfalls occur in the area of maximum energy picking. Complex situations, where different events cross along the ratio direction, pose a significant challenge for the automated picker. Better picking algorithms, or maybe interactive techniques, can resolve this problem. This is an area for future work, together with more experiments on both real and synthetic data.

Another direction for future work, with more relevance to velocity analysis, is the extension of the current method to prestack data and to 3-D common-azimuth data. Once we have obtained the picking surface, we can cut directly though the prestack images to get the one with the best focusing and the flattest CIGs.