Visco-acoustic Reverse-time Migration Using the Pseudo-analytical Method

We derive a new reverse-time migration solution that uses a pseudo-analytical, two-way extrapolator in order to compensate for attenuation losses in visco-acoustic media. The algorithm permits large time stepping and shares the advantages of spectral methods in allowing coarse computational grids. The extrapolation accounts for spatial variations in attenuation by using a series expansion approximation of the equations for constant attenuation. We apply the new scheme to a dual-sensor field survey from the North Sea, in which the resolution of the images is clearly improved after compensating for attenuation.