南黄海太阳沙西侧潮流脊槽的沉积物分布特征和沉积环境演变

对南黄海太阳沙西侧潮流脊槽区进行了底质调查,采用密集站位的振动活塞柱状沉积物采样器取样。根据粒度分析结果,比较精细地研究了厚度约2～3 m浅表层沉积物的空间分布特征。结果表明:表层沉积物中,细砂主要分布在潮流脊和岸滩上,其它较细的沉积类型主要分布于潮流槽内,呈显“脊砂槽泥”的沉积地貌基本特征。同时,沙脊上的表层细砂的分布范围明显与沙脊至海岸的距离有关,除了潮流的影响外,主要与外侧沙脊的消浪作用有关。另外,根据表层沉积物分布的沉积地貌特征,探讨了潮流脊槽的沉积环境演变。

Sedimentary distribution and evolution of sedimentary environment in the tidal sand ridges and troughs west of Taiyangsha Ridge in the southern Yellow Sea

Sediment survey was carried out in the tidal sand ridges and troughs west of Taiyangsha Ridge in the southern Yellow Sea. Samples were taken with vibrating piston sampler in dense stations. Based on results of grain size analyses, the space distribution characteristics of the surface and shallow sediments with thickness some 2~3 m were elaborately studied. The results show that fine sands of the surface sediments mainly distribute on the tidal sand ridges and coast beach, while other finer sediment types mainly distribute in tidal troughs, appearing a basic feature of sediment-morphology pattern of “ridge-sand and trough-soil”. Meanwhile, the distribution scope of the surface fine sands on the tidal sand ridges is clearly related to the distance between the ridges and the coast. Apart from the influence of tidal currents, this is mainly due to the wave energy consumption by the outer ridges. Based on the above characteristics of sediment-morphology pattern, evolution of sedimentary environment was also discussed.