Progress in the use of acoustics to classify marine sediments

Raytheon Company, in conjunction with the University of New Hampshire, is engaged in a multi-year study of the application of acoustics to the determination of marine soils physical and engineering properties. These investigations being conducted under SEAGRANT sponsorship are presently in their third year. Initial research efforts directed towards the parallel development of both a field theoretical model and extension of the more simplistic plane-wave model have lead to a preliminary design concept, instrumentation and computer aided analysis techniques for an operational remote acoustic sediment classification system. Current output is in the form of digital computer print out detailing the measured and calculated sediment properties. Field test results employing acoustic systems in classifying marine sediments; the correlations of physical sampling with precision measurements of compressional wave velocity and amplitude reflection coefficients are reported.