| Popis: |
KIOST-HYU joint acoustics experiment was performed on the western shallow water off the Taean peninsula in the Yellow Sea in May 2013. In this paper, mid-frequency (6~16 kHz) bottom loss data measured in a grazing angle range of 17 ~60° are presented and compared to the predictions obtained using a Rayleigh reflection model. The sediment structure of the experimental site was characterized by multi-layered sediment and the components of the surficial sediment consisted of various types of particles with a mean grain size of 5.9 ϕ. The model predictions obtained using the mean grain size were not in agreement with the measured bottom loss, and those obtained using the grain size of 4 ϕ, which was estimated by an inversion process, showed a best fit to the measurements. It would be because the standard deviation of the gain-size distribution of surficial sediment is 4.3 ϕ, which is much larger than those of other areas around the experimental site. Finally, the model predictions obtained using the geoacoustic parameters estimated from the inversion process for the surficial sediment layer and those corresponding to the mean grain size of 1.3 ϕ for lower layer are reasonably agreement with the measured bottom loss data.Keywords: Bottom loss, Rayleigh reflection coefficient, Geoacoustic parameters, Geoacoustic inversionPACS numbers: 43.30.Ma, 43.30.Pc†Corresponding author: Jee Woong Choi |
