Lessons from the deep – Processing ocean bottom seismic data

Abstract

Summary Imaging results from early ocean bottom seismic (OBS) surveys were markedly superior to existing streamer surveys (both narrow azimuth and wide azimuth), and this led to a sustained campaign of OBS acquisition and processing over the majority of Shell’s producing assets in the deepwater Gulf of Mexico. The multi-level nature of OBS data requires some changes as compared to steamer processing, but most steps can be accomplished with conventional imaging software. Many processes can be applied node-by-node, including demultiple and migration, which yields significant advantages in fast-track processing. Full azimuth OBS surveys, with its associated advantages for velocity model updating and imaging, are clearly superior to streamer surveys and have become a standard for development quality imaging.