Highly accurate seismic depth imaging (migration) is required by the oil/gas exploration industry in regions of complex geology. Fourier-domain depth-imaging techniques provide the needed accuracy although the cost of computation can be large when the lateral velocity variation is rapid. Parallel computers provide an efficient solution to overcome the computational barrier of Fourier-domain imaging techniques. In this paper, a new Fourier-domain imaging technique, based on nonstationary filtering and wavefield extrapolation theories, is described. The amount of computation required for an example 2D synthetic seismic data set is analyzed. The parallel version of the algorithm is implemented using C++ and Fortran 90 on an Alpha cluster workstation. The Message Passing Interface (MPI) library was used for data distribution and collection. The algorithm, found to be accurate but slow on serial machines, can achieve a speed acceptable for most industrial applications.