【摘要】 本文通过对南海海底沉积物样品的声学物理参数和沉积粒度特征统计分析,发现了高、低含砂量沉积物的声学物理特征存在明显差异,建立了海底沉积物的含砂量与压缩波速度、孔隙度、含水量和密度等经验公式,分析了含砂量变化与沉积物的体积压缩模量和密度变化的关系,从声速理论基础上阐明了含砂量变化引起沉积物压缩波速度变化的内在原因是含砂量变化引起了体积压缩模量和密度发生了变化,说明了含砂量增大引起沉积物压缩波速度增大的内在原因是含砂量增大引起了体积压缩模量变化量大于密度变化量,从而在数据统计和理论分析结合基础上,论证了含砂量是影响海底沉积物压缩波速度的重要因素之一。这一研究对声学方法反演海底沉积物粒度参数和沉积物类型、地声参数转换模型的建立,以及对水声反演海底和海底资源勘探等方面都具有重要理论意义和应用价值。更多还原

【Abstract】 Based on the statistical analysis of the acoustic physical parameters and sedimentary grain size characteristics of the South China Sea sediment samples, it is found that there are significant differences in the acoustic and physical properties for high and low sand content. Empirical formulae are established for sand content and compression wave velocity, porosity, water content and density of seafloor sediments. Based on the theory of sound velocity, the reason for the change of compressive wave velocity caused by the change of sand content is that the volumetric compressive modulus and density change with sand content. The reason for the increase of the compressive wave velocity caused by the increase of sand content is that the increase of sand content causes the compressive bulk modulus to change more than the density change. Combination of data statistics and theoretical analysis demonstrates that sand content is one of the important factors affecting the compression wave velocity of seafloor sediments. This study has important theoretical significance and application value for the acoustic inversion of seafloor sediment particle size parameters and sediment types, the establishment of geoacoustic parameter conversion models, and the exploration of seabed resources.更多还原