Internal multiple attenuation for OBN data with overburden/target separation

Areas with complex overburdens pose a major challenge for seismic imaging of deep targets. Reduced illumination can compromise velocity estimation and the image at the target level. A solution to this problem is given by ocean bottom node (OBN) acquisitions. They provide increased illumination through larger offsets and full azimuthal coverage. In these complex cases, another issue that might arise is that of internal multiples. Strong reflectors in the overburden can generate internal multiples, which will be imaged incorrectly as artifacts. These artifacts may have detrimental effects on interpretation and amplitude analysis. The pre-salt in the Santos Basin, offshore Brazil is a good example of this scenario, where both illumination and internal multiples contribute to affect imaging in the target areas. While internal multiple attenuation (IMA) methods have been widely studied in the case of streamer acquisitions, a full solution tailored to OBN acquisitions is still lacking. We propose a solution based on a method recently proposed for streamer acquisitions.