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南海北部及周边地区近代陆源沉积物稀土元素配分模式总体相似,接近上地壳平均成分(PAAS),在重稀土含量上则略为偏高,LaN/LuN比值明显小于PAAS.但是珠江主要支流西江沉积物的稀土元素含量略高于PAAS,在重稀土分布态势上明显偏轻,LaN/LuN比值明显大于PAAS.南海北部地区近代沉积物钕同位素分布具有明显的区域性,主要受控于珠江源区和闽粤沿海源区以及台湾岛源区.闽粤沿海地区εNd(0)值最大,西江沉积物最小,台湾岛以及海域中沉积物εNd(0)值介于两者之间.沿伶仃洋-东沙岛连线,在该线东北区域钕同位素值相对偏高,西南区域相对偏低.珠江源沉积物主要影响该线西南区域,源区母岩以发育大量古生代碳酸盐岩为特征.闽粤沿海源区以及台湾岛源区,主要影响该线东北区域,闽粤沿海源区母岩以发育大量中新生代花岗岩为特征.由于源区母岩成分上的不同,造成沉积物在重稀土含量、Sc/Ti比值以及εNd(0)值上存在明显差异.发育在东沙群岛东南侧高沉积速率堆积体的陆源物质超过80%来自南海北部源区即闽粤沿海源区以及台湾岛源区,来自珠江源的陆源沉积物不超过20%.
The distribution pattern of REE in modern terrigenous sediments is similar in recent years to the northern part of the South China Sea, and close to the upper crustal average composition (PAAS), slightly higher in heavy rare earth content, and the LaN / LuN ratio is obviously less than PAAS. However, the main tributaries of the Xijiang River sediments The content of rare earth elements is slightly higher than that of PAAS, the distribution of heavy rare earths is obviously lighter and the ratio of LaN / LuN is obviously higher than that of PAAS. Neodymium isotope distribution of modern sediments in the northern South China Sea is obviously regional, The coastal areas of Fujian and Guangdong and the island source area of Taiwan.The values of εNd (0) in the coastal areas of Fujian and Guangdong are the largest, the sediments in the Xijiang River is the smallest, εNd (0) Dongsha Island, the neodymium isotope value is relatively high in the northeast region of the line and relatively low in the southwest region.The sediments of the Pearl River source mainly affect the southwestern region of the line, and the parent rock of the source region is characterized by a large number of Paleozoic carbonate rocks. Guangdong coastal source area and Taiwan island source area, mainly affecting the northeastern region of this line, and the source rocks in the coastal areas of Min and Yue are characterized by a large number of Mesozoic and Cenozoic granites.Due to the different composition of parent rocks in the source area, sediments Heavy rare earth content, Sc / Ti ratio and εNd (0) value.During the high sedimentary rate sediments in the southeast of Dongsha Islands, more than 80% of the terrestrial materials come from the source areas of the northern South China Sea ie the coastal areas of Fujian and Guangdong and Taiwan In the source area, no more than 20% of the terrigenous sediments from the Pearl River source.