关键词: 氟沉积体系;西南极海

Abstract:

The fluorine content in bulk sediment and the pore water in Western Antarctic Ocean has been revealed in this paper, 200-395μg / g and 1.18-1.92μg / ml respectively, far below the average reported previously about the world oceans (540μg / g and 2.7μg/ml, respectively). This paper also shows the distribution of the fluorine in sediments of the area is mainly controlled by the chemical composition of the material from the surrounding islands, and the element seems to be incorporated by the hornblende at the most extent, thus the correlation between the element and the hornblende amount in the sediments can be expressed statistically as following: F=217+lnVh. The low concentration of fluorine in the pore water is largely due to the weak weathering process in the islands and the precipitation of the element with calcium, which can be demonstrated as well by the lower value of that in anion-exchangeable (HCO7) F~in the studied area, only about a tenth of that in Pacific Ocean and a quarter in south China and a half in east Zhejiang coast. In addition, the decomposition of the organic matter in the sediment will proba-bally provide fluorine to the pore water but which can be captured easily by the solid phase. Therefore, the possible mechanism of the element's transition and redistribution in the sedimentary system can be preliminarily described as: Early diagenesis decomposition Calcium compounds F Org.F-pore water F-Solid phase