Improving the Image: 5D Interpolation and COV Gathering of a MegaBin ™ Survey

Using new processing technologies, it has become possible to improve the images and usefulness of MegaBin ™ 3D seismic surveys shot in areas of limited structure such as the Western Canadian Sedimentary Basin (WCSB). Two technologies are examined here: 5D interpolation and pre-stack time migration (PreSTM) of Common Offset Vectors (COV’s). MegaBin surveys are designed to be interpolated. The new 5D interpolation method allows the interpolation of these surveys pre-stack, preserving azimuthal and offset amplitude variations. Thus it is a natural extension to the MegaBin processing workflow. This technology is tested on a well-shot 3D seismic survey from the WCSB, where the data can be decimated to produce a MegaBin geometry. These decimated data are then interpolated and compared to the original data, both post-stack and pre-stack. COV’s are natural tools that allow the maintenance of azimuth and offset information through migration. They are used on wide-azimuth surveys, such as a MegaBin, in order to retain the azimuth and offset information for later azimuthal analysis, such as seismic fracture detection. The migration of COV’s is tested on this dataset to make certain that this technology, especially when combined with 5D interpolation, produces images that are comparable to those generated by conventional PreSTM