渤海金州湾全新统沉积物声速与土力学参数的相关性  

Correlation Between the Sound Velocity and the Geotechnical Mechanical Parameters of the Holocene Sediments in the Jinzhou Bay of the Bohai Sea

作　　者：王方旗 华清峰 刘森波 冯义楷 WANG Fangqi;HUA Qingfeng;LIU Senbo;FENG Yikai(First Institute of Oceanography,MNR,Qingdao 266061,China;Key Laboratory of Ocean Geomatics,MNR,Qingdao 266061,China)

机构地区：[1]自然资源部第一海洋研究所,山东青岛266061 [2]自然资源部海洋测绘重点实验室,山东青岛266061

出　　处：《海岸工程》2024年第3期171-181,共11页Coastal Engineering

基　　金：山东省自然科学基金项目(ZR2023MD119);国家自然科学基金项目(41606056)。

摘　　要：声速是海底地声学研究中的基本物理量和重要参数,研究其分布特征及其与土力学参数之间的相关性具有重要的科学意义和实用价值。基于渤海金州湾的高分辨浅地层剖面数据和钻孔取样试验数据,通过反演计算获得了全新统内微细层序的声速数据及与之对应的沉积物土力学参数数据集,从而对沉积物的声速特征及其与土力学参数之间的相关性进行研究。结果表明:金州湾全新统的平均声速为1.505~1.734 km/s,平均值为1.601 km/s;粉砂、粉土、淤泥、淤泥质黏土和淤泥质粉质黏土五种沉积物类型的声速平均值分别为1.734、1.645、1.511、1.588、1.567 km/s,变化趋势大致反映了声速随粒径和含砂量的减小而减小的特征;声速与湿密度、干密度和压缩模量之间均存在较显著的线性正相关关系,与孔隙比、含水率、液限、塑性指数和压缩系数之间均存在较显著的线性负相关关系,而与塑限之间的相关性一般,与液性指数无相关性。Sound velocity is a fundamental physical quantity and one of the important parameters in the study of seafloor geoacoustics.It is of great significance and practical value for studying the sound velocity distribution and the correlation between the sound velocity and the geotechnical mechanical parameters of the sediments.Based on the high-resolution sub-bottom profile data and the borehole sampling test data obtained in the Jinzhou Bay of the Bohai Sea,the sound velocity data and the corresponding physical and mechanical property parameter datasets of the micro-sequences in the Holocene sediments are obtained by inversion calculations.Thus,the sound velocity characteristics of the sediments and the correlations between the sound velocity and the physical and mechanical property parameters of the sediments are studied.The results show that the average sound velocity in the Holocene sediments in the Jinzhou Bay ranges from 1.505 to 1.734 km/s,with the mean value being 1.601 km/s.The average sound velocity values in five types of sediments such as silt sand,silt,mud,muddy clay and muddy silty clay are 1.734,1.645,1.511,1.588 and 1.567 km/s,respectively.This variation trend roughly reflects that sound velocity in the sediments decreases with the decrease in particle size and sand content.There is a significant positive linear correlation between the sound velocity and the wet density,dry density and compression modulus of the sediments and a significant negative linear correlation with the void ratio,water content,liquid limit,plastic index and compression coefficient.However,the correlation between the sound velocity and the plastic limit of the sediments is poor and there is no correlation with the liquid index.

关 键 词：沉积物声速 物理性质 土力学参数 金州湾全新统 相关性 

分 类 号：P733.23[天文地球—物理海洋学]