南黄海西部陆架区表层沉积物稀土元素及其物源分析

对南黄海西部陆架区486个表层沉积物样品的稀土元素进行了测试分析。结果表明:稀土元素总量分布特征受粒度影响,其含量总体上随平均粒径的减小而升高,但在局部站位其含量还可能受矿物控制。稀土元素相关参数,如轻重稀土元素分异度、铈异常以及铕异常基本不受粒度影响,而主要受源岩组分控制,可以进行有效的物源判别。研究区不同站位沉积物中稀土元素配分曲线均为右倾的负斜率模式,相对富集轻稀土元素,显示中等程度的铕负异常,无明显铈异常。稀土元素相关参数物源判别表明研究区物质主要来源于黄河。

RARE EARTH ELEMENTS IN SURFACE SEDIMENTS OF WESTERN SOUTH YELLOW SEA AND THEIR PROVENANCE IMPLICATIONS

Rare earth elements were analyzed for the 486 surface samples taken from the western South Yellow Sea.It was found that the contents of rare earth elements increase with the decrease in mean grain size.Mineralogy is another factor to be considered in some stations.The parameters of the Rare earth element,such as the ratio between light rare earth element and heavy rare earth element,Eu abnormity and Ce abnormity have nothing to do with grain size but mainly controlled by the source rock compositions.Therefore,they could be used as effective means to define the provenance of the sediments.The distribution pattern of rare earth elements shows that the chondrite-normalized rare earth element partitioning curve inclines to the right,indicating the enrichment of light rare earth elements.There is moderate negative Eu abnormity,but no Ce abnormity at all.The parameters of the rare earth elements in the study area denote a provenance from the Yellow River.