南极普里兹湾表层沉积物的元素组合特征及物源分析

STATISTICAL EVALUATION OF THE ELEMENTAL COMPOSITION AND SOURCE ANALYSIS OF SURFACE SEDIMENTS IN PRYDZ BAY,ANTARCTICA

利用中国南极科学考察第18—27航次在普里兹湾获得的20个表层沉积物样品,测定了其中C、N、Ca和Ti等多种常、微量元素的含量,分析了元素组合对指示物源的意义,探讨了普里兹湾的沉积环境和物质来源。结果表明:研究海域表层沉积物中元素含量的变异系数均较大,元素的平面分布、相关性和聚类特征出现两种模式;一类以OC、TN和S元素为主的元素组合指示了海洋生物来源,而另一类元素组合K、Ti和Rb等指示了陆源碎屑来源;湾内中心及东南部区域的沉积作用主要受控于上层水体的生物生产,而西侧的弗拉姆浅滩和艾默里冰架前缘陆架区的沉积物则包含大量冰筏碎屑的输入。

A number of major and trace elements including C,N,Ca,and Al were measured in 20 surface sediment samples collected from Prydz Bay,Antarctica,during the CHINARE 18—27 cruises. The distributions of these elements and their characteristics of association were used to explore the sedimentary environment and material sources within the study area. The results showed that the values of most of the elements in the surface sediments changed over a wide range. Furthermore,the elemental distribution,correlation,and clustering features presented two patterns. One represented by OC,TN,and S that indicated a source of marine organisms,and the other represented by K,Ti,and Rb that indicated a source of terrigenous clastics. The results also suggested that sedimentation at the center of Prydz Bay and the southeastern area was controlled by biological production,whereas sedimentation near the Fram Bank and continental shelf in front of the Amery Shelf,contained a large number of ice-rafted clasts.