Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica

知识价值：南大洋过程在第四纪晚期冰期-间冰期气候变化中发挥重要作用。然而，新涌出的温暖富含营养的绕极深水对南极冰冻圈的直接影响仍然是推测的。PI建议使用对南极边缘沉积物的精确测年晚第四纪古海洋学研究和一套在南极普里兹海峡现有的三个冰川海洋沉积物岩芯上测量的地球化学指标来检验这一假设，即环极深水海洋热对南极洲-S冰盖在冰川消融期间的物质平衡产生负面影响。具体地说，PI将利用这些数据重建Lambert冰川/amery冰架系统的第四纪晚期历史；评估Lambert冰川/amery冰架系统在最后一次冰川消退期间的时间、速度和风格，以及评估环极深水入侵对晚第四纪Lambert冰川/amery冰架系统的影响。硅藻结合放射性碳和光激发发光技术将被用来获得普里兹海峡硅质泥质渗流层段的精确地层年龄控制。此外，PI将测量沉积10Be浓度，以确定硅质泥浆渗出单元的来源，并追踪冰架前缘位置的过去变化。广泛影响：该建议将支持职业生涯早期的女科学家，并将为女性/少数民族研究生和本科生提供专业发展和研究经验。少年派将利用美国联邦大学S女孩海洋夏令营的优势。

Intellectual Merit: Southern Ocean processes play an important role in Late Quaternary glacial-interglacial climate change. However, the direct influence of newly upwelled warm nutrient-rich Circumpolar Deep Water on the Antarctic cryosphere remains speculative. The PI proposes to test the hypothesis that Circumpolar Deep Water-derived ocean heat negatively impacts the mass-balance of Antarctica?s ice sheets during deglaciations using precisely dated late Quaternary paleoceanographic studies of Antarctic margin sediments and a suite of geochemical proxies measured on three existing glacial marine sediment cores from the Prydz Channel, Antarctica. Specifically, the PI will use these data to reconstruct the Late Quaternary history of the Lambert Glacier/Amery Ice Shelf system; evaluate the timing, speed, and style of retreat of the Lambert Glacier/Amery Ice Shelf system during the last deglaciation, and to assess the impact of Circumpolar Deep Water intrusions on the Lambert Glacier/Amery Ice Shelf system in the Late Quaternary. Diatom bound radiocarbon and optically stimulated luminescence techniques will be used to obtain precise stratigraphic age control for the Prydz Channel siliceous muddy ooze intervals. In addition, the PI will measure sedimentary 10Be concentrations to determine the origin of the siliceous muddy ooze units and to track past changes in the position of the ice shelf front.Broader impacts: This proposal will support an early career female scientist and will provide professional development and research experiences for women/minority graduate and undergraduate students. The PI will take advantage of USF?s Oceanography Camp for Girls.