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以厦门西海域表层沉积物为对象,研究了沉积物中稀土元素(REE)的分布特征。结果表明:厦门西海域沉积物中REE含量为125.71~206.02μg.g-1,西部港湾区的8号和九龙江口的2号采样点REE含量较高,且轻稀土占绝对优势。REE含量随沉积物粒级呈有规律的变化,REE含量最高的是<63μm的粒级,最低的是>250μm的粒级;沉积物经球粒陨石标准化后,各粒级REE总体配分曲线相近,均表现为明显的Eu亏损和Ce亏损,且<63μm粒级亏损尤为严重。Eu与Ce异常平均值均小于黄河流域和长江流域沉积物;<63μm粒级的沉积物中轻重稀土分馏程度最高,但在其他三种粒级沉积物中由粗到细分馏程度逐渐降低。分馏现象表明细粒级沉积物轻重分馏较粗粒级明显。与当地土壤稀土元素背景值比较,沉积物主要来自厦门西海域本地的土壤。
Based on the surface sediments in the west of Xiamen, the distribution characteristics of rare earth elements (REEs) in sediments were studied. The results show that the content of REE in the sediments from the west coast of Xiamen is 125.71 ~ 206.02μg.g-1, the REE content of the No.2 and the Jiulongjiang estuary in the western harbor area is higher, and the light rare earth is the absolute dominant. The content of REE changed regularly with the grain size of sediments. The highest content of REE was <63μm and the lowest was> 250μm. After the sediments were normalized by chondrite, the overall distribution curves of REE of each size were similar , All showed obvious Eu loss and Ce loss, and <63μm grain size loss was particularly serious. The average anomalies of Eu and Ce are less than that of the Yellow River and the Yangtze River sediments. The fraction of light and heavy rare earths fractionated in the sediments <63μm is the highest, but gradually decreases from coarse to fine fractionated in the other three types of sediments. Fractionation shows that fines fractionation of finer-graded sediments is more pronounced than coarse fraction. Compared with the background value of the local soil rare earth element, the sediment mainly comes from the local soil in the west sea area of Xiamen.