Caractérisation des fonds marins par acoustique : état de l'art et perspectives

Acoustical characterization of the sea-floor may be performed in different ways depending of the type of system to be used. Several techniques are presented here for sea-bed identification using mono-beam echo-sounders (time signal analysis, second echo amplitude) and side scan sonars (spectral analysis, image texture). New possibilities are provided by recent multi-beam echo-sounders, performing both bathymetry measurements and imagery. The previous techniques could be used for these systems, together with direct measurements of reflectivity angular dependence. Finally are presented here some results obtained in deep water with a low frequency multibeam sounder