Application of 3D source deghosting and designature to deep-water ocean bottom node data

Abstract

Compared to towed-streamer data, deep-water ocean bottom node (OBN) data by nature have a broader bandwidth; however, the presence of the source ghost and source signature can reduce the useful frequency range and therefore decrease seismic resolution. Deep-water OBN data are typically well sampled in the common-receiver domain; thus, the source-side wave-propagation angles can be obtained through plane-wave decomposition for 3D source deghosting and designature. We compared two methods for broadening the bandwidth of deep-water OBN data: (1) 3D source deghosting that assumes a single-point source and (2) 3D joint source deghosting and designature that takes into account the full source-array geometry. Using Gulf of Mexico (GOM) OBN data, we demonstrated that 3D source deghosting effectively removed the source ghost to provide images with a wider spectrum and a better signal-to-noise ratio (S/N). We also found that joint 3D source deghosting and designature can further increase the bandwidth compared to 3D deghosting alone.