摘要
沉积物粒度参数可以用来反演沉积物沉积的水动力条件和沉积环境。根据对南汇边滩采集的表层沉积物粒度资料进行分析,结果表明:沉积物类型以黏土质粉砂为主;随着沉积物平均粒径Mz的减小,分选逐渐变好,偏态由极正偏向正偏转变,并向近对称接近。运用Pe- jurp的三角图式对沉积环境进行划分,结果表明南汇东滩的水动力条件总体上较强,沉积物粒径总体上偏粗,属于径流—潮流共同作用的河口浅滩沉积环境。对潮流底应力和沉积物临界起动切应力的计算进一步印证了该区水动力较强,对应沉积物颗粒偏粗的现象。
Sediment size parameters are related to the depositional hydrodynamic conditions associated with the local sedimentary environment. Under the analysis of sediment samples collected on Nanhui subfluvial flat, the result shows that the clayey silt is the main sediment type, the sorting become well and the skewness transforms from very objective to objective with decreasing of the main size of sediment. Furthermore, a triangular diagram advanced by Pejurp was used to subdivide the sedimentary environment, the result shows that the hydrodynamic on this area is relatively strong and the grain size is generally coarser, and this area belongs to estuarine sedimentary environment influenced by both flow current and tide current. With the calculation of tidally-induce near bed shear stress and the critical near bed shear stress, the result corresponds well with the phenomena of coarser grain size.
出处
《海洋湖沼通报》
CSCD
北大核心
2008年第1期32-38,共7页
Transactions of Oceanology and Limnology
基金
上海市科委重大科技攻关项目(04DZ12049)
关键词
南汇东潍
沉积物粒度
水动力
Nanhui subfluvial flat
sediment gain size
hydrodynamic
