山东半岛靖海湾及其附近海域悬沙粒度特征及再悬浮作用研究

Characteristics of grain size distribution and resuspension process of suspended sediment in Jinghai Bay and its adjacent waters,Shandong Peninsula

表层沉积物再悬浮作用研究一直是海洋沉积动力学中的重点和难点问题。本文尝试通过对靖海湾及其附近海域的现场观测资料及悬浮体的室内分析,对悬沙粒径的时空分布特征及其与悬沙浓度、流速的关系进行讨论,并对研究区域表层沉积物的再悬浮特点进行研究。结果表明:研究区域悬沙粒径由西向东呈现逐渐减小的趋势,而在垂向上悬沙粒径差别不大;根据潮周期内悬沙粒径、悬沙浓度、流速的变化特征及6个站位的悬沙级配曲线,推断在一个潮周期内表层沉积物出现了2次再悬浮,再悬浮产生的颗粒粒径在100～300μm,各站潮周期内的最大再悬浮量在1.49×10-3～6.66×10-3kg/m3之间。

The study of resuspension process and its mechanism of surface sediment is of difficulty but the key to marine sedimentary dynamics.On the basis of the measurement of suspended sediment grain size parameters and current velocity in the Jinghai Bay and its adjacent waters,the characteristics of grain size distributions and resuspension process of suspended sediment are analyzed.The results show that the mean grain size of suspended sediment decreased from the west to the east of the study area,and it was slightly coarser from the bottom to the top in vertical.The relationship among mean grain size,suspended sediment concentration and current velocity was significant.There were two resuspension processes during a tidal cycle.The grain size of resuspended sediment was between 100~300μm,and the mean content of the suspended sediment generated by resuspension was 1.49×10-3~6.66×10-3kg/m3 at the bottom layers.