Pb Isotopes in the Southern Ocean: A Study of Pb Systematics and Continental Weathering During the Eocene/Oligocene Transition

南大洋的铅同位素：始新世/渐新世过渡期间的铅系统学和大陆风化研究

• 批准号: 0926474
• 负责人: Ellen Martin
• 金额: $ 29.58万
• 依托单位: University of Florida
• 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: 2009-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0926474&HistoricalAwards=false
• 关键词: Pb; Isotopes; Southern; Ocean; Study

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This award supports a research effort to construct deep water Pb isotopic records across the "Greenhouse-icehouse" (Eocene/Oligocene boundary) transition using six Ocean Drilling Program sites located in the Southern Ocean. The project goals are to expand understanding of: 1) seawater Pb systematics in this region, and 2) continental weathering processes during the evolution of the Antarctic cryosphere. In terms of systematics, records extracted from bulk sediments will allow study of the stratification of the water column with respect to Pb, providing information about the input and transfer of Pb to deep waters. In addition, the PI will evaluate whether Southern Ocean inputs are dominated by Pb advected into the basin with water masses from the Atlantic and Pacific, or by Pb derived internally from local weathering. A comparison between seawater and detrital Pb isotopes will also be used to evaluate the intensity of chemical versus mechanical weathering during growth of the Antarctic Ice Sheet, with a detailed evaluation across a weathering pulse identified by Nd isotopes. Provenance studies based on crossplots of seawater Pb isotopes will yield information about source regions and input sites. This award will also support graduate and undergraduate research experiences, outreach activities within the local community, and material for classroom discussions and exercises.

该奖项是根据2009年《美国回收与再投资法》（公法111-5）资助的。该奖项支持一项研究工作，以构建“温室冰”（始新世/渐新世边界）的深水PB同位素记录海洋钻井程序地点位于南大洋。项目目标是扩展对以下方面的了解：1）该地区的海水PB系统，以及2）在南极冰冻圈进化过程中大陆风化过程。 在系统学方面，从散装沉积物中提取的记录将允许研究水柱相对于PB的分层，从而提供有关PB输入和转移到深水的信息。 此外，PI将评估南洋输入是由PB主导的，PB以来自大西洋和太平洋的水质量或从当地风化的内部衍生而成的PB。海水和碎屑PB同位素之间的比较也将用于评估南极冰盖生长过程中化学强度与机械风化的强度，并在ND同位素确定的风化脉冲中进行了详细的评估。 基于海水PB同位素的交叉图的出处研究将产生有关来源区域和输入地点的信息。 该奖项还将支持研究生和本科研究经验，当地社区内的外展活动以及课堂讨论和练习的材料。