Prestack Depth Migration of Dual-AzimuthSurveys incorporating Azimuthal P-waveAnisotropy

摘要

It is standard practice now to build velocity models for prestack depth migration that include polaranisotropy (vertical or tilted transverse isotropy 'VTI' or 'TTI'). In this paper, we discuss a dual-azimuthNorth Sea dataset that exhibits significant azimuthal anisotropy as well as polar anisotropy.We present a practical production workflow using innovative analysis techniques ('butterfly gathers')and solve for the azimuthal anisotropy using two sets of anisotropic parameters with a single velocityfield, taking advantage of the fact that we are dealing with only two dominant azimuths.