Using discrete low-frequency components of shipping noise for gassy sediment characterization in shallow water

This work shows that normal-mode attenuation coefficients can be extracted from ship noise and used to estimate the sound speed in gas-saturated sediments. In an experiment in the Sea of Galilee, a research vessel served as a noise source approaching a vertical hydrophone array at a constant speed. Twelve narrow-band components of the vessel noise in the frequency band 20–100 Hz were identified and mode filtered to estimate the normal-mode attenuation coefficients. The inversion results indicate that the sound speed in the sediments was approximately 170 m/s.