Focusing or absorption?

Highly absorptive rocks usually have low velocity. Behind a low velocity pod, waves should be weakened by absorption. They should also be strengthened by focusing. Which effect dominates? How does the phenomenon depend on spatial wavelength? A full reconstruction of the physical model remains to be done. Maybe you can figure it out knowing that black on Figure 9c denotes low amplitude or high absorption, and black on Figure 9d denotes low velocities.

EXERCISES:

1. Consider waves converted from pressure P waves to shear S waves. Assume an S-wave speed of about half the P-wave speed. What would Figure 7 look like for these waves?