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Transfering wave-field checkpoints from disk to the compute engine is often a bottleneck in Reverse Time Migration (RTM). The need to create wave-field checkpoints can be eliminated by running the wave equation backwards and choosing a time reversible boundary condition. In acoustic propagation, velocity can be made more and more random within a boundary region. Reflections from the incoherent boundaries are random in nature and produce minimal coherent correlations when applying the RTM imaging condition. In Vertical Transverse Isotropic (VTI) media, the horizontal and Normal MoveOut (NMO) velocities can be modified to cause wavefronts to propagate parallel to the boundary region causing further degradation of coherent signals. Coherent reflections can be further reduced by decreasing the randomized velocity within the boundary region.