珠江口底质元素含量分布特征及其地球化学意义

Geochemistry element contents and distributions in the surface sediments of the Pearl River Estuary

珠江口底质常、微量元素分析结果表明,富含Si、Al、K、Mg、Fe和Ti等元素的陆源物质构成本区沉积物主体,主要元素氧化物平均含量分别为SiO261.16%,Al2O314.74%,Fe2O35.72%,TiO20.88%,MgO1.84%,K2O2.63%,CaO2.70%,CaCO34.79%。底质元素含量与沉积物粒度组成关系密切,主要元素Al2O3、MgO、Fe2O3、TiO2以及微量元素Cu、Pb、Zn、Cr、V、Co、Ni、Ba在西北部近岸区以及伶仃洋中部细颗粒沉积区内富集;而SiO2、CaO、Zr、Sr则在西南部和东南部粗颗粒沉积区富集。控制本区沉积物地球化学特征的因素主要有物质来源、沉积环境、水动力条件、沉积物粒度、矿物组成以及元素自身地球化学性质等。

The analysis results of constant elements and trace elements in the surface sediments indicate that ome terrigenous materials rich in Si, AI, K, Mg, Fe, Ti are the main components of the sediments in the Pearl River Estuary. The average levels of the main elements of oxides are SiO2 61.16%, Al2O3 14.74%, Fe2O3 5.72%, TiO2 0.88%, MgO 1.84%, K2O 2.63%, CaO 2.70%, and CaCO3 4.79%. Element content and particle size are closely related, with the main elements of Al2O3, MgO, Fe2O3, TiO2, as well as trace elements Cu, Pb, Zn, Cr, V, Co, Ni, Ba, in the northwestern coastal area and central Lingdingyang fine-grained sediment areas, of SiO2, CaO, Zr, Sr in the southwestern and southeastern district coarse sediment enrichment. The main factors that control the geochemical characteristics of sediments in this area are the source material, sedimentary environment, hydrodynamic conditions, sediment particle size, mineral composition and geochemical nature of the elements themselves.