How to obtain true amplitude common-angle gathers from one-way wave equation migration?

True amplitude wave equation migration (WEM) provides the quality image of wave equation migration along with proper weighting of the output for estimation of an angularly dependent reflection coefficient, similar to the output of Kirchhoff inversion. In an earlier paper, Zhang et al. (2003) presented a true amplitude WEM for common-shot data in heterogeneous media. Here we present two additional true amplitude heterogeneous media WEM techniques to produce common-angle gathers. The first is based on the same common-shot image gathers, while the second is based on a modified double-square-root one-way wave equation. True amplitude common-shot migration was based on an imaging condition using the ratio, pU /pD . In contrast, common-angle gathers require the product pU p ∗ D in the imaging condition. We demonstrate this new method with a simple synthetic example.