南极菲尔德斯半岛全新世以来湖泊沉积的环境演变研究

本研究利用南极菲尔德斯半岛长城站附近的西湖沉积物 ,研究该地区的环境变化状况。对 1 993年采集的 9.2 8m长的西湖岩芯 (GA - 7)进行等间距分样 (2cm) ,进行了有机碳、δC1 3org、磁化率和粒度等环境指标分析。利用本研究区湖相沉积物的1 4C测年数据 ,发现距今 1 2 60 0年以来 ,南极菲尔德斯半岛地区至少出现过四次气温升高时期 ,即 480 0 - 4 4 0 0aB .P .、360 0 -3350aB .P .、2 1 0 0 - 1 80 0aB .P .和 90 0aB .P .-现在。研究同时发现 ,湖相沉积物的有机碳含量和δC1 3org存在显著正相关关系 ,可以作为环境温度的替代性指标

HOLOCENE ENVIRONMENTAL CHANGE DELIVERED FROM LAKE CORE IN FILDES PENINSULA OF KING GEORGE ISLAND, ANTARCTIC

Lake core taken from Xihu in Fildes Peninsula of King Gorge Island, Antarctic could reveal the environmental change of the district.The lake core(GA 7)was 9.28 meters long and divided at 2 cm intervals. Through measuring the organic carbon,magnetic susceptibility,grain size and organic carbon isotope of GA 7 lake core , it was estimated by use of 14 C age data that there were four periods of higher temperature in Fildes Peninsula: 4800-4400aB.P., 3600-3350aB.P., 2100-1800aB.P. and 900aB.P.- present. Meanwhile, results show that there is a strikingly positive correlation between contents of organic carbon and that of organic carbon isotope(δC 13 org ) which could be the substitute indicators of environmental temperature.