One‐return wave equation migration: Imaging of duplex waves

Abstract

Conventional one‐way wave equation migration has been widely applied to prestack depth imaging. Both source and receiver wavefields are recursively downward continued with a convolution imaging condition at each depth level. The one‐way propagator handles primary reflections, but neglects turning waves, multiples and other multiple reflections such as duplex waves. Based on the concept of multiple fore‐scattering and single back‐scattering, one‐ return wave equation migration extrapolates both down‐ going and up‐going waves. Followed by a properly designed imaging condition, one‐return migration produces the depth image of primary reflections that is same as one‐way migration as well as the image from the contribution of duplex waves. A synthetic example is presented to demonstrate the unique capability of this approach to image the vertical features.