Multi-azimuth Seismic Data Imaging in the Presence of Orthorhombic Anisotropy

The presence of orthorhombic anisotropy can severely affect the imaging of multi- and wide- azimuth data. Analysis of multi-azimuth (MAZ) data often reveals noticeable fluctuations in moveout between different acquisition directions, preventing constructive summation of MAZ images. Vertical transverse isotropy (VTI) effects can also cause well misties and higher order moveout. We have developed an approach for imaging in the presence of orthorhombic anisotropy. Both synthetic and real data from offshore Australia show that our approach can take into account the co-existing HTI/VTI effects of orthorhombic anisotropic media, reduce the structural discrepancies between seismic images built for different azimuths, producing a constructive summation of MAZ dataset, resolving well misties, and delivering a step-change in the final seismic image quality.