Compensating for visco‐acoustic effects in reverse‐time migration

Abstract

Anelastic properties of the earth cause frequency dependent energy attenuation and phase distortion in seismic wave propagation. These unwanted effects are preferred to be corrected in a prestack depth migration. Based on the dispersion relation under a linear attenuation assumption, we derive a visco‐acoustic wave equation in the time domain and apply it in a prestack reverse time migration to compensate for the anelastic effects in the seismic data. The equation is defined by a pseudo‐differential operator, and the energy increases with frequencies when back propagating the seismic data in migration. Using a regularization process, we show that our method provides stable and amplitude balanced reverse time migration images.