In-situ acoustic properties of the main types of sediment in the offshore areas of China
The acoustic properties of the surficial sediment at the seafloor are essential influential factors in underwa-ter sound propagation and acoustic detection;different sediment types show distinct acoustic properties.Aiming at the demand of marine acoustic research for quickly obtaining the acoustic property parameters at the seafloor,based on the in-situ survey data of the acoustic properties and the testing data on the sediment samples at 100 stations ob-tained in recent years,this paper conducts statistics on the acoustic properties such as the sound speed and attenua-tion coefficient and the physical properties such as the mean grain size and density of eight typical sediment types in the offshore areas of China.By comparing the survey data and the statistical results of the predecessors,it is shown that they have excellent consistency with the data obtained in multiple in-situ survey systems;however,parameters such as the sound speed ratio and attenuation factor obtained by Hamilton are substantially high.The calculation re-sults obtained using the frequency dispersion model based on the VGS theory show that the overhigh Hamilton statis-tical results are not completely caused by the higher survey frequency.For the marine areas lacking direct survey data,the statistical results in the paper provide a scheme for estimating preliminarily the acoustic properties at the seafloor based on the sediment type.
sediment typesound speedacoustic attenuationfrequency dispersionin-situ measurementdensityporosityoffshore areas of China
国家科技期刊平台
NSTL
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