Reverberation

Reverberation is the multiple bouncing of waves between layers. Waves at vertical incidence in a water layer over the earth can develop clear, predictable, periodic echos. FGDP gives a detailed theory for this. At nonzero shot-to-geophone offset, the perfect periodicity is destroyed, i.e., multiple reflections no longer have a uniform reverberation period. In a model earth with velocity constant in depth, normal-moveout correction restores the uniform reverberation period. Mathematical techniques for dealing with reverberation in the presence of depth-variable velocity are described in considerable detail in IEI.