Multiple aliasing problems in marine data

Series of linear, steep noise have frequently been observed on post-stack marine data. Such aliased noise is closely associated with data acquired with large shot spacings, in our case mostly 3D data acquired with multiple sources and streamers. In many cases, the noise has been observed to penetrate the objective area of seismic sections and cause significant deterioration of the primary reflections. This paper reports on results of recent studies which have demonstrated that such noise is caused by aliasing of multiples. Some solutions are proposed.