海底表层沉积物声速特性研究进展与探讨

海底表层沉积物具有多相、多颗粒、多形态的组成结构，导致其声学特性复杂多样。通过分析压缩波速度和切变波速度特性的研究现状，指出有待于解决的科学问题和关键技术问题。在分析国内外有关海底沉积层声速特性研究基础上，提出采取系统、可控的实验测量手段解决当前测量存在的4点问题。综合分析了压缩波速度和切变波速度存在的统计回归关系和理论分析关系，探讨了当前地声反演、采样样品声学测量、原位声学测量3种方法存在的测量尺度、测量频率、测量状态等的差异，探讨建立不同测量方法和测量技术对测量结果进行统一性解释的方法，从而获得不同类型、不同区域的海底表层沉积物真实的声速特性。最后，从实验室声学测量、物理力学参数测量、流固耦合特性分析、原位测量及海底监测、采样测量与原位测量的误差分析及校正、海底大纵深声学测量6个方面提出技术需求，为提高声学探测海洋和海底的精度服务，推动海洋声学探测和海洋工程发展。

Research progress and discussion on sound velocity characteristics of seafloor surface sediments

The seafloor surficial sediments have multiphase, multi-particle and multi-morphological structures, which lead to complex and diverse acoustic wave propagation process. Based on the analysis of the characteristics of compressional wave velocity and shear wave velocity, the scientific problems and key technical problems to be solved are pointed out. On the basis of analyzing the research status of sound velocity characteristics at home and abroad, this paper suggests that a systematic and controllable experimental measurement method to solve the four problems existing in current measurement. With a comprehensive analysis on the relationship between compressional wave velocity and shear wave velocity including their regression relation and theoretical analysis, differences on measuring scale, measuring frequency, and measurement status are discussed for current three kinds of methods including geoacoustic inversion, samples acoustic measurement, and in-situ acoustic measurement. And also the methods on the consistency of explanation for measurement results of different measurement methods and measurement techniques are discussed, to obtain the real seabed sediment acoustic characteristics of different types and different regions. Finally, six technical demands are presented such as the laboratory measurement of physical and mechanical parameter measurement, acoustic analysis of fluid solid coupling characteristics, in-situ measurement and monitoring of submarine sediments, error analysis and correction between sampling analysis and in-situ measurement, and the surface acoustic measurement technology of deep sediments, with the aim to improve the accuracy of acoustic detection of the sea and the seafloor, and promote development of ocean engineering.