BOUNDARY-CONDITIONS AND THE SOURCE-TERM FOR ONE-WAY ACOUSTIC DEPTH EXTRAPOLATION

The one-way acoustic wave equations can be derived, using eigenvalue d ecomposition of the two-way wave equation in the Fourier domain, in su ch a manner that the source term and the free-surface boundary conditi on are explicitly introduced. The proposed form of the one-way wave eq uations is well adapted to seismic reflection modeling because it allo ws a pressure field recorded at the surface to be extrapolated directl y in depth. A numerical example illustrates the appropriate implementa tion of the source term and the free-surface boundary conditions. A co mparison with a two-way modeling shows a good agreement of the compute d wavefields.