中国近岸海区沿岸流和海岸流对沉积物的搬运
SEDIMENT TRANSPORTATION OF LONGSHORE CURRENT AND COASTAL CURRENT IN CHINA LITTORAL ZONE
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摘要: 中国近岸海区存在两种海流:沿岸流和海岸流。前者是波浪产生的,主要搬运破波带以内的沉积物。后者是中国边缘海环流系统的一部分,位于破波带外,主要搬运粉砂和黏土细粒沉积物。在一些中文文献中两者都称作"沿岸流"。这容易形成概念上的混乱和分析问题上的错误。为了避免混淆,属于边缘海环流系统一部分的"沿岸流"应该称作海岸流,对于具体的"沿岸流"如"渤莱沿岸流"可以直接称呼为渤莱海流。两种海流的方向可以相同、相反或者呈一定角度。山东北部海岸沉积物的空间分布明显地受波浪、近岸环流系统(沿岸流、裂流)及海岸流控制。Abstract: The zonal sediment distribution in the coastal zone near Yantai (from Penglai to Chucun, Weihai) results from the processes of wave, wave-produced longshore current and coastal current. Sand is distributed from high tidal level to 10 m water depth and mainly controlled by wave and longshore current. And the sediment source is from the coastal land nearby. Sand-silt-clay is mainly distributed in 10~15 m water depth. A part of sediments are the Yellow River derived sediments transported by the coastal current and a part from nearby small rivers is transported by the wave and nearshore circulation. Clayey silt and silt are distributed in the water depth of 15~20 m. They are the Yellow River derived sediment transported by the coastal current.