Selective stacking in the reflection‐angle and azimuth domain

I analytically demonstrate the artifacts in angle-domain commonimage gathers caused by sparsely sampled wavefields, from a perspective of shot-profile migration. The local-offset gather is linearly related to the angle gather in locally constant-velocity media when wavefields are sufficiently well sampled, but not when wavefields are poorly sampled. Hence, linear slant-stack or radial-trace transform in local-offset gathers will produce angle gathers with artifacts, which may hinder further interpretation or analysis and reduce the quality of the final stacking image in the angle and azimuth domain. Instead of simply stacking along reflection angle and azimuth axes, I present a method to compute the stacking weights as functions of angle and azimuth and make the stacking process selective. My method is tested on the synthetic wide-azimuth version of the SEG/EAGE salt data set, where a cleaner image with higher signal-to-noise ratio is obtained.