Knowledge of the acoustic arrival angle can be useful for studying penetration mechanisms and for estimating sediment sound speed dispersion. The arrival angle of acoustic energy penetrating the sediment water interface, however, is difficult to measure using sparsely distributed pressure sensors. The arrival angle, as well as amplitude information, can be unambiguously obtained by measuring particle motion with directional receivers. An experiment was conducted off of Elba Island in 1999 to assess the feasibility of using of high-frequency accelerometers to measure directionality. Measurements of acoustic penetration onto a sandy seafloor were obtained over wide frequency range (2.5 to 29 kHz) using the accelerometers. Results from the experiment demonstrating this novel measurement technique will be presented, as will issues concerning accelerometer design and calibration.
