渤海底质沉积物粒度特征及输运趋势探讨

Discussion on grain-size characteristics of seafloor sediment and transport pattern in the Bohai Sea

基于对渤海171个表层沉积物样品的粒度分析测试结果,使用Gao-Collins粒径趋势分析方法,研究了渤海底质沉积物的分布特征和输运趋势,结果表明:渤海粗粒级沉积物主要分布于辽东和渤中浅滩附近,在滦河口和黄河口也有零星分布;细粒级沉积物主要分布于渤海湾中部和南部,并呈条带状向辽东湾方向延伸;细粒级沉积物分选较粗粒级沉积物好,偏态系数较低;渤海细粒级沉积区为渤海的现代沉积中心,周边沉积物有向这个沉积中心汇聚的输运趋势。这种沉积物分布格局和输运趋势主要受潮流和渤海环流的控制。

The grain-size distribution and transport pattern of seafloor sediment collected from the Bohai Sea were studied using grain-size data and Gao-Collins grain-size trend analysis method.The results show that coarse-grained sediment is mainly distributed on Liaodong and Bozhong shoals and occurs occasionally near the Luanhe and Huanghe mouths;fine-grained sediment mainly covers the central and southern part of Bohai Gulf and extends farther to the west of Liaodong Gulf.The fine-grained sediment is better sorted with lower skewness compared with the coarse-grained sediment;the fine-grained sediment area is considered to be a modern depositional center of the Bohai Sea and the sediment outside the center displays a net transport trend toward it.The distribution and transport pattern of sediment in the study area are proposed to be controlled by tidal currents and circulations.