Collaborative Research: Evolution of the deep South Atlantic since the last interglacial period inferred from a depth transect of Cape Basin sediment cores

合作研究：从开普盆地沉积物岩心的深度横断面推断出末次间冰期以来南大西洋深处的演化

• 批准号: 1131778
• 负责人: Christopher Charles
• 金额: $ 19.58万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-15 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1131778&HistoricalAwards=false
• 关键词: Collaborative; Research; Evolution; deep; South

There is considerable evidence that the deep ocean plays some role in governing the evolution of Pleistocene ice ages and interglacial periods. Yet after several decades of research, there is still debate over the degree to which sedimentary tracers can distinguish differences in deep ocean circulation between ice age oceans and the modern ocean. This collaborative project will investigate past ocean circulation changes by generating multi-proxy records for several common paleoceanographic tracers (including benthic d18O and d13C, radiocarbon, Cd/Ca, Zn/Ca and B/Ca) for eight time slices over the last glacial-interglacial cycle using cores along a depth transect from the Namibian margin and Cape Basin. These time slices would represent the step in evolution from interglacial state through a full glacial cycle. The research will focus around a series of questions concerning water mass evolution in the Atlantic Ocean, the connection between circulation and carbon cycling, differences between conservative and non-conservative proxies, and the possibility for major boundary condition changes distinct from ocean mixing effects. Broader impacts:This project will provide a detailed picture of the mixing between the two principal deep water masses of the world's ocean across a full ice cycle, which will be of widespread use to oceanographers and climate scientists. Funding will support two Ph.D. students and provide significant experience in proxy data collection and interpretation. The project will also serve as a platform for a summer REU fellow and provide support for several undergraduate students to learn research and laboratory techniques. Additionally, funding will help develop a lesson on deep earth circulation through the Deep Earth Academy at Texas A&M University.

有大量证据表明，深海在控制更新世冰期和间冰期的演化过程中发挥着一定作用。 然而，经过几十年的研究，对于沉积示踪剂能够在多大程度上区分冰河时代海洋和现代海洋之间的深海环流差异，仍然存在争议。 该合作项目将通过为几种常见的古海洋示踪剂（包括底栖 d18O 和 d13C、放射性碳、Cd/Ca、Zn/Ca 和 B/Ca）生成上一次冰期八个时间切片的多代理记录来调查过去的海洋环流变化。使用沿纳米比亚边缘和开普盆地深度横断面的岩心进行间冰期循环。 这些时间切片代表了从间冰期状态到整个冰河周期的演化步骤。 该研究将重点围绕大西洋水团演化、环流与碳循环之间的联系、保守和非保守代理之间的差异以及与海洋混合效应不同的主要边界条件变化的可能性等一系列问题。更广泛的影响：该项目将提供世界海洋两个主要深水团在整个冰循环中混合的详细图片，这将被海洋学家和气候科学家广泛使用。 资金将支持两名博士生。学生并在代理数据收集和解释方面提供丰富的经验。 该项目还将作为 REU 暑期研究员的平台，并为几名本科生学习研究和实验室技术提供支持。 此外，资金将有助于通过德克萨斯农工大学的深地地球学院开设有关地球深部循环的课程。