AMS Dating of Arctic Lake Sediments

该奖项支持对一系列北极湖泊沉积物岩心的研究，该计划旨在确定在这些材料上获得可靠的C-14年代的最佳方法。湖泊沉积物中的古气候记录非常完整地记录了气候变化；因此，这些样本对于研究过去一千年和数万年来发生的变化至关重要。早先的研究表明，由于水生植物和生物吸收了化石和重新加工的碳，以及吸收了溶解的碳酸盐，所以对湖泊沉积物进行放射性碳测年可能是有问题的。该项目是科罗拉多大学INSTAAR小组与亚利桑那大学AMS放射性碳测年实验室的专业知识相结合的协调努力。这项研究计划将侧重于从沉积物的各种物理和化学分离中提取C-14信息，作为一系列湖心深度的函数，这些岩心既显示了“可靠的”日期，也显示了“有问题的”日期。该项目将允许制定程序，为预期增加的北极湖沉积物研究提供更可靠的数据。

This award supports the study of a series of Arctic lake-sediment cores in a program to ascertain the best methods of obtaining reliable C-14 dates on such material. The paleoclimate record in lake sediments gives a very complete record of climatic change; these samples, therefore, are critical for the study of changes which have occurred over the last millennium, and tens of millennia. Earlier studies have demonstrated that radiocarbon dating of lake sediments can be problematic, due to the incorporation of fossil and reworked carbon, and uptake of dissolved carbonate by aquatic plants and organisms. This project is a coordinated effort combining the expertise of the INSTAAR group at the University of Colorado with that of the AMS radiocarbon dating laboratory at University Arizona. This research program would focus on extracting C-14 information from a variety of physical and chemical separates of sediment as a function of depth in a series of lake cores showing both "reliable" and "problematic" dates. This project will allow the development of procedures to produce more reliable dates for the expected increase in the study of Arctic lake sediment.