莱州浅滩表层沉积物的分布特征及影响因素
STUDY OF THE SURFACE SEDIMENT DISTRIBUTION IN LAIZHOU SHOAL AND INFLUENCING FACTORS
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摘要: 以莱州浅滩附近148个表层沉积物粒度资料为基础,结合潮流场数值模拟和泥沙起动流速计算资料,分析了莱州浅滩表层沉积物分布特征,初步探讨了研究区表层沉积物分布格局的形成机理及影响因素。结果表明,莱州浅滩表层沉积物由滩顶向两侧,粒径变细,分选性变差;物源和浅滩形态控制着研究区的沉积物整体分布格局,而浅滩特有的水动力条件则导致沉积物发生进一步分异:滩顶沉积物的分布主要受波浪和潮流的联合作用,两侧沉积物的分布则主要由浅滩两侧的潮致环流控制。Abstract: Based on the data of 148 surface sediments from the Laizhou Shoal, together with the results of numerical simulation of the tidal current field and the sediment incipient flow rate, the characteristics of surface sediment distribution at the shoal are preliminary revealed, and the formation mechanism of the surface sediments distribution pattern of the study area is discussed. The result shows that from top to the bottom of the shoal, the particle size of surface sediments is decreasing, and the sorfing gets poorer. The overall distribution pattern of sediments is mainly controlled by the source of sediments and the morphology of the shoal, and the unique hydrodynamic condition of the shoal leads to further differentiation. The distribution pattern of sediments on the top of the shoal is mainly affected by the combined effects of wave and tidal current, but the distribution pattern of sediments on the bottom of the shoal is mainly controlled by the water circulations induced by the tidal current.