Kirchhoff Simulation, Migration, and Inversion using Finite Difference Traveltimes and Amplitudes

High frequency asymptotic approximation of the acoustic Green's function leads to efficient modeling and migration methods for primaries only reflection seismograms. A volume (as opposed to interface) oriented description of reflectivity allows symmetry between modeling and migration. With proper selection of amplitudes and discretization, the migration and modeling operations are mathematically adjoint, hence suitable for use in iterative inversion algorithms. Further simplifications are possible under the additional assumptions that incident and reflected rays carry significant high-frequency energy propagate near the vertical and arc first arrivals. Then the necessary traveltime and amplitude tables may be computed by efficient high order finite difference solution of the eikonal and transport equations. Careful ordering of the operations results in an accurate algorithm far more efficient than direct finite difference solution of the primaries-only (linearized) wave equation. 1 Int..