Low wavenumber reflectors

John C. Bancroft

A numerical modelling environment was created to accurately evaluate reflections from a 1D interface that has a smooth transition shape between the two different velocities. The objective was to accurately propagate a chirp through the transition zone, where the size of the transition zone is similar to the wavelengths within the chirp.

Transition zones in the shape of a raised half-cosine were evaluated using the incident and reflected chirps. The shape of the reflectivity is a half-sine. Reasonable matches were obtained.