Seawater Calcium Isotopes and the Oceanic Ca Cycle

海水钙同位素和海洋钙循环

• 批准号: 9730781
• 负责人: J. Douglas Macdougall
• 金额: $ 19.89万
• 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: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-02-15 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9730781&HistoricalAwards=false
• 关键词: Seawater; Calcium; Isotopes; Oceanic; Ca

Calcium is a major dissolved species in seawater with a residence time of about a million years. Its sources include rivers and hydrothermal fluids, as well as small amounts via sediment diagenesis. Ca is also tied to the carbon cycle via carbonate precipitation in the oceans. The PI proposes that detailed measurements of Ca isotopic variations in present day Ca sources and sinks will shed light on the details of the oceanic Ca cycle. Such data could then be used to interpret past changes in Ca isotopic abundances, which would ultimately be related to climatic variability and changes in global carbonate preservation and temperature fluctuations. The PI has demonstrated the ability to make these unique measurements with the high precision necessary to study Ca cycling, and he proposes to make new measurements in existing samples of river water, hydrothermal fluids and marine sediments and basalts. These data, together with existing seawater results, would provide a signifcant advance in our understanding of the oceanic Ca cycle.

钙是海水中主要的溶解物质，其停留时间约为一百万年。其来源包括河流和热液，以及少量通过沉积物成岩作用。钙还通过海洋中的碳酸盐沉淀与碳循环联系在一起。 PI建议，详细测量钙同位素变化在当今的钙源和汇将揭示海洋钙循环的细节。 这些数据可以用来解释过去钙同位素丰度的变化，这将最终与气候变化和全球碳酸盐保存和温度波动的变化。 PI已经证明有能力以研究Ca循环所需的高精度进行这些独特的测量，他建议在现有的河水，热液和海洋沉积物和玄武岩样品中进行新的测量。 这些数据与现有的海水结果一起，将为我们对海洋钙循环的理解提供一个显着的进步。