北黄海南部近岸海域表层沉积物稀土元素分布特征及影响因素

    Distribution characteristics and influencing factors of rare earth elements in surface sediments in the southern nearshore waters of the North Yellow Sea

    • 摘要: 根据北黄海南部近岸海域52个站位表层沉积物和7条主要入海河流沉积物样品粒度和稀土元素(REE)测试结果,分析了研究区沉积物粒度和稀土元素含量的平面分布特征,并探讨了稀土元素分布的影响因素。结果表明,研究区表层沉积物大致呈由近岸向海粒度变细的特征。研究区稀土元素含量普遍高于长江、黄河和中国黄土等地区,总体呈轻稀土富集、重稀土亏损的特点。稀土元素的含量及分布特征受粒度特征、矿物成分、风化作用及物质来源等多种因素影响,其中,矿物成分对研究区稀土元素的影响较为显著,稀土元素的高含量可能与陆源碎屑矿物(长石类矿物、含钛矿物等)的富集有关;粒度的影响主要反映在重稀土元素更容易富集在细粒组分含量较高的沉积物中;风化作用对稀土元素的影响主要是通过多种物源混合完成。研究区稀土元素所指示的物质来源以黄河为主。

       

      Abstract: The surface sediments of 52 stations in the coastal waters of the southern part of the North Yellow Sea and the sediments of 7 main inflowing rivers were sampled, and the sample particle size and rare earth elements (REE) were tested. Based on this, the particle size and REE content in the study area were analyzed. Planar distribution characteristics of REE content, and the influencing factors of REE distribution were discussed. Results show that the surface sediments in the study area generally exhibit the characteristics of finer grain size from nearshore to seaward. The content of REEs in the study area is generally higher than those in the Changjiang (Yangtze) River, Huanghe (Yellow) River, and Chinese loess areas, and is generally characterized by the enrichment of light REE and depletion of heavy REEs. The content and distribution characteristics of REEs are affected by various factors such as grain size characteristics, mineral composition, weathering and material sources. Among them, mineral composition has a more significant impact on REEs in the study area. The high content of REE may be related to the enrichment of land-sourced detrital minerals (feldspar minerals, titanium-containing minerals, etc.). Particle size characteristics and weathering have a certain effect on the distribution of REEs in the fine-grained sediments. The effect of weathering on rare earth elements is mainly accomplished through the mixing of multiple sources.The material sources indicated by REEs in the study area are mainly sediments from the Huanghe River.

       

    /

    返回文章
    返回