Rayleigh-Sommerfeld modelling with AVO

Joanna Kathleen Cooper, Gary F. Margrave, John M. Maweu

Using ray tracing to compute angles of incidence at each reflecting interface, angle-dependent reflection coefficients were introduced into the 3D Rayleigh-Sommerfeld modelling method. Previously, the method, which is based on phase-shifting of the wavefield, was limited to laterally varying, but angle-independent reflection coefficients. This advancement allows for the inclusion of realistic amplitude variation with offset (AVO) effects in model data produced by the Rayleigh-Sommerfeld method. An example in a constant velocity medium demonstrates that the modelled amplitudes closely match the expected AVO curves. The method was then applied to generating shot records over a channel model. Inspection of the shot records and subsequent migrations demonstrate the success of the method in simulating AVO effects in a complex stratigraphic setting.