MEASUREMENTS OF SOUND SPEED AND ATTENUATION OF MARINE SEDIMENTS BY THE SOUND TUBE METHOD

摘要

The sound speed and the attenuation coefficient of water saturated marine sediments sampled in Setouchi (the Inland Sea of Japan) and Hekinan Coast of Japan were measured by the sound tube method in a frequency range from 6.6kHz to 11.0 kHz. The grain diameter distribution, the porosity and the density of the sediments were also measured for each sample, measurements in a frequency range from 40 kHz to 250 kHz were supplementary carried out by the free field method. The sound speed and the attenuation coefficient are theoretically estimated based on Biot-Stoll model on the acoustic wave propagation through fluid saturated porous media. Both measured and theoretically estimated results are compared and the validity of Biot-Stall model is discussed.