Shallow Water Tomography

Abstract

Ocean acoustic tomography has been successfully demonstrated in deep ocean areas for transmission by wholly refracted paths. Other areas of the ocean such as straits, gulfs and the continental slope and rise are characterized as acoustically shallow having bottom limited transmission with sound paths that makes multiple interactions with the ocean floor. Since the vertical excursion of ray paths is confined in shallow water the differences in arrival time, amongst various ray paths, is usually small resulting in received pulses that overlap in time and cannot be cleanly separated. The forward scatter from bottom interactions transmits down the channel and is also received and serves to broaden pulses and produce a reverberation background which further complicates the tomographic interpretation of measured and channel pulse responses.