Reverse-time migration (RTM) is a powerful migration method provided that an accurate velocity model can be constructed. In any discrete operation on a sampled field we need to consider aliasing before, during, and after that operation. Reverse-time migration takes a sampled seismic experiment and creates an image of the subsurface. In reverse-time migration the sampled wavefield and the forward modelled shotfield are propagated as a solution to the wave equation. This often requires re-sampling the data to a regular sampled and finer grid for wavefield propagation. Additionally aliasing can occur when cross-correlating the two wavefields to form an image.
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