北冰洋美亚海盆南部是源自劳伦泰德冰盖和东西伯利亚冰盖的冰筏碎屑（Ice-rafted Debris, IRD）的主要沉积区，并受冰消期淡水卸载的直接影响，是研究冰盖扩张和淡水卸载的理想海域。本项目拟以美亚海盆南部4个岩心为研究对象，基于AMS14C测年、古地磁及沉积物颜色反射率、XRF、有孔虫属种等建立年代地层框架，通过沉积物中全岩矿物衍射分析（XRD）、＞63μm的IRD的矿物学、Sr-Nd同位素组成等查明IRD的物质来源并定量估计各个物源端元的贡献量，探讨不同冰盖来源的IRD贡献比例随时间的变化特点及搬运路径，重建大区域上晚第四纪以来劳伦泰德冰盖和东西伯利亚冰盖的扩张历史。通过分析沉积物中自生Fe-Mn氧化物的Nd同位素组成，重建淡水卸载事件及其对北大西洋Heinrich事件的响应，查明美亚海盆南部晚第四纪以来淡水卸载对北极深层水团形成的影响。

The southern Amerasian Basin is the mainly sedimentary area of ice-rafted debris transported from Laurentide Ice Sheet (LIS) and East Siberia Ice Sheet (ESIS), and this area also affected by freshwater discharge events in deglacial, which is an ideal area to research ice sheet expansion and freshwater discharge events. The project uses four cores in the southern Amerasian Basin as the research objects, and establishe chronostratigraphic frameworks based on the AMS14C dating, paleogeomagnetic, sediment color reflectivity, XRF and foraminifer species, etc. Data for mineralogy and isotopic geochemistry can be used as indicating the provenances for IRD with the grain size of ＞63μm and quantitatively calculating the respective contributions of different sources, variations in different sources IRD contributions with time can be used to infer individual ice sheet growth, variability and decline of ice sheets. By analyzing the Nd isotopic composition of authigenic Fe-Mn oxides in the sediments, the freshwater discharge events and its response to Heinrich events will be analyzed, and the contributions for the formation of the Upper Polar Deep Water (UPDW) and Polar Deep Water (PDW) will be revealed.