摘要
基于在南黄海中部海域获得的大量海底沉积物样品及其测试数据，分析讨论了该区域海底浅表层沉积物声阻抗特性及其与沉积物物理力学性质参数的相关关系。研究表明：研究区浅表层沉积物声阻抗呈现出分区域分布的特征，可分为西南部声阻抗高值区、东北部声阻抗低值区以及北西东南向声阻抗梯度带3个区域。通过回归分析，建立了声阻抗与沉积物物理力学参数的经验回归方程。结果表明：声阻抗与密度、含水率、孔隙比、孔隙度、液限、塑限、塑性指数、压缩系数等参数的相关性较好，判定系数 R2一般大于0．8，而与砂粒含量、黏粒含量、中值粒径、抗剪强度等参数的相关性相对较差，判定系数 R2一般小于0．7。将声阻抗与物理力学性质的相关性和声速与物理力学性质的相关性进行了对比，结果表明，声阻抗与上述参数的判定系数 R2均大于声速与上述参数的判定系数，从而表明声阻抗是一个能够更好地反映声学特性与物理力学性质关系的沉积物声学特性参数。
Abstract
Based on the sediment cores collected in the middle area of the Southern Yellow Sea and the core data measured in the laboratory ,the properties of the acoustic impedance of shallow seafloor sediments and the correlations between the acoustic impedance and the physical parameters of the sediments are analyzed .The data analysis demonstrates that the acoustic impedance is characterized with a zonal distribution pattern , and its distribution can be divided into three sub-zones:a low acoustic impedance sub-zone in the northeast , a high acoustic impedance sub-zone in the southwest and an acoustic impedance gradient band aligning from northwest to southeast . The empirical regression equations between the acoustic impedance and the physical-mechanical parameters of the sediments are established by means of regression analysis . The results indicate that the acoustic impedance is well correlated to the parameters such as density ,percent moisture ,porosity ratio ,percent porosity ,liquid limit ,plastic limit , plasticity index and compression coefficient , with the coefficient R2 which is generally larger than 0 .8 ,but poor correlated to the parameters such as sand content ,clay content , median grain size and shear strength ,with the correlation coefficient R2 w hich is commonly less than 0 .7 .Comparing the correlations between the acoustic impedance and the physical-mechanical parameters to that between the sound speed and the physical-mechanical parameters of the sediment shows that the former correlation coefficient R2 generally larger than the latter one .This result indicats the acoustic impedance could be a better sediment acoustic parameter that can reflect the relationships between the acoustic properties and the physical-mechanical parameters of the seafloor sediments .
NETL
NSTL
维普
万方数据