Surface Diffraction Noise Attenuation for Marine Seismic Data Processing With Mathematical Morphological Filtering

Surface diffraction noise (SDN) is a kind of coherent noise and pervasive in marine seismic data acquisition. This kind of noise is intractable during seismic data processing. We present a new method based on mesh scanning and mathematical morphological filtering (MMF) to attenuate the SDN in marine surveys. The idea of mesh scanning will be first put forward to get the energy-map of the survey. Compared with the traditional mesh scanning method, the energy-map computing formulas will be improved to protect the reflections from the recognition of SDNs, especially the shallow reflections. All the possible surface diffractors will be shown on the computed energy-map with strong energy. Then, a 2-D mathematical morphological closing operation will be innovatively used to get the upper envelope of the energy-map and reduce the number of the possible surface diffractors with a maximal value picking. After confirming all the possible surface diffractors on the energy-map, the travel-time curves of SDNs could be calculated easily according to the kinematic propagation law of seismic wave for all the related shot gathers and the MMF will be used to extract all the SDNs along the trajectories of them within appropriate time windows. Both a real 2-D and a real 3-D marine seismic data will be processed by the proposed method to show the positive effects in attenuating the SDNs.