Reverse time migration of multiples: Applications and challenges

Abstract

Marine seismic acquisitions record both primary and multiple wavefields. In a typical processing sequence, multiple energy is removed from the data before migration. However, valuable information might be contained in the multiple wavefield. A modification is proposed to the standard reverse time migration (RTM) algorithm to enable correct imaging between the primary wavefield and the first-order multiple wavefield. The advantages of this modification, reverse time migration of multiples (RTMM), are evaluated through three real data-processing projects and identified three key advantages. First, RTMM can recover small-angle reflections critical for shallow-water imaging that are missing in the primary wavefield. Second, RTMM has a wider illumination coverage, which significantly extends the image for an ocean-bottom node (OBN) project. Third, RTMM produces an image complementary to the primary image in a complex geologic setting, possibly assisting with interpretation. In addition, a synthetic study is presented of two types of cross-talk noise that hinder the full potential of RTMM, and corresponding practical strategies are proposed to handle them.