Conclusions

This section shows that we can reformulate prestack Stolt residual migration such that it becomes applicable to depth-migrated images. In essence, the residual migration introduced here is a Stolt-stretch method; therefore, it retains both the advantages and the disadvantages of Stolt-type techniques.

The main benefit of this method is that we can residually migrate by assuming given ratios between the current and updated velocities, rather than fixing the new velocities directly. In this way, we can apply Stolt residual migration to images that have been migrated with an arbitrary velocity map, not only to those migrated with constant velocity. This conclusion is valid for all types of seismic images, from 2D post-stack, to 3D prestack, including 3D common-azimuth.

The method discussed in this section is cheap to apply; therefore one of its main uses is in the area of repeated residual image enhancement, with applications to wave-equation migration velocity analysis, or as a simple technique to create velocity maps in field exploration.