Comparison of in   situ compressional wave speed and attenuation measurements to Biot–Stoll model predictions

• Published in: The Journal of the Acoustical Society of America Vol. 112; no. 5_Supplement; p. 2254
• Main Authors: Kraft, Barbara J., Mayer, Larry A., Simpkin, Peter G., Goff, John A.
• Format: Journal Article
• Language: English
• Published: 01-11-2002
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.4778977

The importance of estimating acoustic wave properties in saturated marine sediments is well known in geophysics and underwater acoustics. As part of the ONR sponsored Geoclutter program, in situ acoustic measurements were obtained using in situ sound speed and attenuation probe (ISSAP), a device developed and built by the Center for Coastal and Ocean Mapping (CCOM). The location of the Geoclutter field area was the mid–outer continental shelf off New Jersey. Over 30 gigabytes of seawater and surficial sediment data was collected at 99 station locations selected to represent a range of seafloor backscatter types. At each station, the ISSAP device recorded 65 kHz waveform data across five acoustic paths with nominal probe spacing of 20 or 30 cm. The recorded waveforms were processed for compressional wave speed and attenuation. Experimental results are compared to predicted values obtained using the Biot–Stoll theory of acoustic wave propagation. Several methods are examined to estimate the required model parameters. The contribution of loss mechanisms to the effective attenuation is considered. [Research supported by ONR Grant No. N00014-00-1-0821 under the direction of Roy Wilkens and Dawn Lavoie.]