2019年长江口南北槽水域表层沉积物特征分析  

Study of surface sediment characteristics in the south and north passages of the Yangtze estuary in 2019 flood and dry seasons

作　　者：刘启雄 陈家祺 刘海江[1] 张东来 LIU Qixiong;CHEN Jiaqi;LIU Haijiang;ZHANG Donglai(College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China;Shanghai Waterway Engineering Design and Consulting Co., Ltd., Shanghai 200120, China)

机构地区：[1]浙江大学建筑工程学院,浙江杭州310058 [2]中交上海航道勘察设计院有限公司,上海200120

出　　处：《海洋工程》2020年第4期100-108,共9页The Ocean Engineering

基　　金：国家重点研发计划资助(2017YFC0405400)。

摘　　要：为探究长江口区域最新的泥沙运动特征,于2019年枯季(1月,21个样本)和洪季(8月,58个样本)在长江口南北槽及周边区域现场取样河床表层泥沙样本,测量了样本的中值粒径和级配分布。采用Folk-Ward公式计算了泥沙样本的粒度参数(分选系数、偏度和峰度),并分析了沙样本内磁性物质含量。基于上述泥沙物理参数,进一步对比分析洪枯季研究区域河床表层泥沙的时空分布变化特征。分析结果表明北槽内洪枯季泥沙样本中值粒径空间分布特征一致,南槽中段洪季泥沙样本中值粒径远小于枯季泥沙样本中值粒径,南槽其他区域洪枯季泥沙样本中值粒径空间分布特征一致。同一中值粒径下,不同沙样本(中值粒径大于63μm)各粒度参数之间差异显著,而泥样本(中值粒径小于63μm)粒度参数间差异相对较小。此外,磁性物质含量测量结果表明枯季沙样本磁性物质组成的空间分布存在一定的差异,而洪季沙样本磁性物质的空间分布相对均一。To reveal the latest sediment characteristics in the Deepwater Navigation Channel of the Yangtze estuary,21 and 58 samples were collected in 2019 dry and flood seasons in this study,respectively.Subsequently,the grain size distributions of sediment samples were measured,and the Folk-Ward formulae were used to calculate the grain size parameters,including sorting coefficient,skewness and kurtosis of collected samples.In addition,the sample’s magnetic composition was obtained through magnetic analysis.After comprehensively analyzing the above results,spatial and temporal characteristics of sediment samples in the target area were compared between the dry and flood seasons.The results reveal that spatial distribution of the median grain size is similar between two seasons in the north passage,as well as the south passage except the middle section where the median grain size of flood season is finer than that of dry season.Regarding the grain size parameters and for a specified medium grain size,obvious differences among sandy samples(medium grain size larger than 63μm)are confirmed,while such differences are insignificant among muddy samples with medium grain size smaller than 63μm.Spatial distribution of magnetic composition of sandy samples presents local feature in dry season,whereas it is rather spatially uniform in flood season.

关 键 词：长江口南北槽 深水航道 洪枯季 泥沙样本 中值粒径空间分布特征 粒度参数 磁性物质含量 

分 类 号：P753[交通运输工程—港口、海岸及近海工程]