Image enhancement

In the first part of our example, we have concentrated on improving the focusing of the image. We achieved this goal by using Stolt residual migration in the prestack domain Sava (1999); Stolt (1996). Of course, Stolt residual migration is not the only possibility, another alternative being velocity continuation Fomel (1997).

Figure 7 shows the image we obtained with a starting velocity model, while Figure 8 displays the image we obtained by applying residual migration to the original. Both images have been created with the same level of clipping. The second image is clearly better focused. We can take the difference between the images in Figures 7 and 8 to be the perturbation in image ($\Delta R$), and use it to invert for the slowness model that generated the improvement in focusing.