东营港海域表层沉积物分布及其运移趋势

DISTRIBUTION CHARACTERISTICS AND TRANSPORT TENDENCY OF SEAFLOOR SURFICIAL SEDIMENTS IN THE DONGYING HARBOR AREA

根据2008年10月东营港海域表层沉积物粒度取样,结合水文观测和相关波浪资料,通过粒度分析以及粒径趋势矢量和掀沙动力等计算,探讨了沉积物的分布特征及其运移趋势。研究表明:东营港海域表层沉积物以黏土质粉砂为主,由岸向海呈"粗-细-粗-细"的条带状分布,相应地形成了沿岸最粗、近岸次细、远岸次粗和外海最细的4个沉积区,呈现出沉积物由粗沉积区向细沉积区运移的趋势;引堤阻隔了两侧潮流运动和波浪传播的连续性,引起引堤-引桥连接部位水流的辐聚或辐散,对于来自NE向的常强浪,引堤北侧为迎波区,南侧为波影区,致使沿岸和近岸的局部水动力场改变,从而造成了引堤南北侧沉积物分布和运移的差异。进一步研究显示,沉积物在总体上呈离岸运移,与余流呈偏东向的离岸流动基本一致。

Based on data of waves, tidal currents and grain size parameters of seafloor surficial sediments measured at the Dongying Harbor area in October 2008,spatial distribution pattern and grain size trend of seafloor sediments were analyzed. The analysis results show that main type of seafloor sediments at Dongying harbor area is clayey silt, the grain size distribution pattern of which is coarse-fine-coarse-fine from coast to sea. These sediments are transported from the coarse-particle zones to the fine-particle zones. The approach embankment and approach bridge obstruct the propagation of tidal currents and waves, and a convergent or divergent flow is formed at the joint part of them. Variation of the local flow field leads to different sediment distributions and transportation patterns between the south and north zones of the approach embankment. A further study shows that transportation of the seafloor sediments is from coast to sea, which is similar to the residual current in direction.