Measurement and Modeling of High‐Frequency Acoustic Properties in Fine Sandy Sediments

Abstract

Abstract The object of this study was to obtain the acoustic properties of fine sandy sediments with approximately 22% clay content from the East China Sea Shelf. This study conducted the in situ acoustic measurement to measure the sound speed and attenuation, and eight sediment cores were collected and measured the wet bulk density, porosity, and mean grain size in laboratory environment. The correlations between in situ sound speed ratio and physical properties show good accordance with two empirical equations, while the in situ attenuation factor deviated the regression curves. Both the sound speed ratio and the attenuation data show the obvious change against the measurement frequency. The comparisons of the measured sound speed ratio and attenuation to the Biot‐Stoll model predictions were performed. The sound speed ratio dispersion agrees well with the model prediction, when the permeability and pore size were calculated using the extended Kozeny‐Carman's equation and the extended Hovem's equation. The attenuation data in this study accords better with the prediction curves reported for fine sediments than that for coarse sediments from the 1999 Sediment Acoustics Experiment.

Keywords

• seafloor sediments
• sound speed
• attenuation
• in situ measurement