南沙海槽区表层沉积物的地球化学特征

GEOCHEMICAL CHARACTERISTICS AND SEDIMENTARY ENVIRONMENT OF SURFACE SEDIMENTS OF SOUTH NANSHA TROUGH AND ADJACENT SEA AREAS

对南沙海槽区 73个表层沉积物的地球化学及沉积环境特征进行了研究。微量元素主要有 Cu、Pb、Zn、Ni、Co、Cr、Sr、Ba和 Zr,表现为亲陆性 ,常量组分为 Si O2 、Al2 O3、TFe、Ca O、Mg O、K2 O、Na2 O、Mn O、P2 O5 、Ti O2 ,表现为边缘海向深海过渡的沉积环境特点。沉积物质含有粘土组分、碳酸盐型生物碎屑组分、陆源碎屑非粘土组分以及火山碎屑、岛源物质 ,沉积环境与水深关系密切 ,在 2 0 0 m以浅 ,沉积物的供给复杂 ,沉积环境多变 ,在 2 0 0 m以深 ,沉积物的供给和沉积环境稳定。

This paper aims at studying on geochemical characteristics and sedimentary environment of surface sediments of the Nansha Trough and adjacent sea areas. Trace elements such as Cu, Pb, Zn, Ni, Co, Cr, Sr, Ba and Zr exhibit a terrestrial nature, and the major elements like SiO 2, Al 2O 3, TFe, Cao, MgO, K 2O, Na 2O, MnO, P 2O 5 and TiO 2, have sediment characteristics from marginal sea to deep sea. The results of factor analysis show that the surface sediments are basically made up of terrestrial, biological, volcanic and island materials. There is an affinity between sediment environment and water depth. Above 200 m, sediment comes from complicated sources and sediment environment is also various, but blow 200 m, sediment sources and environments are stable.