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圆陀角地处长江北支与江苏海岸的交汇处,发育了典型的粉砂淤泥质潮滩,潮滩沉积物元素可记录海岸环境变化的信息。在圆陀角附近潮滩采集了长度为218 cm的YY孔岩芯,常量与微量元素分析结果显示,岩芯沉积物平均粒径与大多数元素之间相关性好,“粒控效应”特征明显。除Ca、Na、Ti、P、Sr外,岩芯大部分元素含量自下向上呈现由低变高再变低的趋势,并在岩芯132 cm深度出现最大值。根据圆陀角附近海岸沙嘴长江北支变迁的证据,苏北岸外海域是长江北支的重要泥沙来源;粒度和粘土校正后的元素含量呈自下而上由低变高的趋势。邻近区域沉积物元素富集系数分析显示,在1956年前后,圆陀角附近潮滩沉积物发生了较大的变化,1956年以前的主要来源于长江,1956年以后演变为主要来源于南黄海辐射沙洲南翼。
Circular Tuojiao is located at the confluence of the north branch of the Yangtze River and Jiangsu Coast, developing a typical silt muddy tidal flat. The tidal flat sediment elements can record the information of the coastal environmental changes. In the tidal flat around Tuojiao, YY-shaped core with a length of 218 cm was collected. The results of constant and trace elements analysis show that the correlation between the average particle size of core sediments and most of the elements is good, "Characteristic is obvious. In addition to Ca, Na, Ti, P, Sr, most of the core elements showed the trend of low to high and then low, and the maximum 132 cm depth of the core. According to the evidence of the vicinal relocation of the Yangtze River in the vicinity of the roundabout on the coast of Xuan Tuo, evidence shows that the waters off the northern Jiangsu coast are the important sediment sources of the northern branch of the Yangtze River. The elemental concentrations after the correction of grain size and clay show a downward trend from low to high. The analysis of enrichment coefficient of sediments in the adjacent area shows that the sediments of the tidal flat near Circular Tuojiao have undergone great changes before and after 1956, mainly from the Yangtze River before 1956, and mainly from the southern Yellow Sea after 1956 Radiation sandbar south wing.