Elimination of free-surface multiples using least-squares redatuming II: Marine seismic data acquired by streamers

Elimination of free-surface multiples is a key step in processing marine seismic data acquired by towed streamers. Shallow water environment poses severe challenges to existing demultiple methods. In a companion paper, based on the reciprocity theory, we have presented a transformation equation between the virtual observation at a subsurface datum and the real seismic data. Accordingly, an approach of least-squares redatuming (LSR) based on constrained optimization inversion was proposed, and has been applied to eliminate free-surface multiples for ocean bottom seismic data. In this paper, based on the same principle, we will discuss the approaches and impact factors of elimination of the free-surface multiple using LSR for two types of marine streamer seismic data, of which one records both fields of vertical particle velocity and acoustic pressure with dual-sensors, and the other only records acoustic pressure with hydrophones. Synthetic data examples reveal the features and effectiveness of the proposed approaches. The processing results of a shallow-water field data acquired by dual-sensors on a towed streamer from the South Yellow Sea demonstrate the potential of the LSR-based approaches in practical applications.