LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals

U 系列定年德雷克海峡深海珊瑚中的末次盛宴和冰川消融放射性碳

• 批准号: 0902957
• 负责人: Laura Robinson
• 金额: $ 20.57万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0902957&HistoricalAwards=false
• 关键词: LGM; Deglacial; Radiocarbon; series; Dated

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project's goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth's system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column.

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。该提案寻求资金，以继续对研究航行期间在德雷克海峡收集的深海珊瑚进行后续分析工作。该项目的目标是进行古气候研究，以限制冰川和冰川消退期间南大洋放射性碳含量的深度结构和时间演变。放射性碳是过去气候的多功能示踪剂;其放射性衰变提供了一个内部时钟，用于评估过程的速率，并可用于追踪碳在地球系统中的运动。它通过海气交换进入海洋，因此，限制这一过程的过程将减少表层和深层沃茨的放射性碳含量。南大洋是深海和大气层之间热量和碳交换的关键地点，那里形成的深海沃茨充满了全球深海和中层海洋的大部分。由于强大的水流往往会冲刷掉沉积物，碳酸盐保存是有限的，放射性碳储层年龄的限制很差，许多传统的古海洋学技术变得不切实际。有人建议通过分析深海珊瑚骨骼的化学成分来缓解这些困难。它们的文石骨架可以使用U系列衰变精确地定年，当与放射性碳分析结合时，将允许计算过去水柱的C14/C12比率。