Collaborative Studies (USC and UM): Fractionation of Ge and Si during Diagenesis, and its Implications for Regulating the Oceanic Ge/Si Ratio

合作研究（南加州大学和密歇根大学）：成岩过程中 Ge 和 Si 的分馏及其对调节海洋 Ge/Si 比率的影响

• 批准号: 9911608
• 负责人: Douglas Hammond
• 金额: $ 17.6万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-03-01 至 2004-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9911608&HistoricalAwards=false
• 关键词: Collaborative; Studies; USC; UM; Fractionation

To understand how the earth's climate might change in response to anthropogenic influence, such as the burning of fossil fuel, it is necessary to understand the natural variability of climate over glacial/interglacial times. One method of studying this variability is through investigation of the deep-sea sedimentary record, which contains chemical, fossil and mineralogic evidence of past climatic conditions. A potentially important signal in the sediments is the ratio of Ge to Si in opal, which varies in response to changing ocean conditions. To derive the maximum use of this tool, its chemical behavior in the sea floor must be fully understood. Therefore, this work will study the fractionation of Ge and Si in ocean sediments by laboratory experiments that would create a controlled diagenetic setting to determine the incorporation of Ge and Si into iron oxyhydroxices and sulfides. Additionally, existing pore water samples will be analyzed to investigate the behavior of Ge in different ocean settings. Field Studies in the California borderland will be carried out to collect additional pore waters and to deploy in-situ benthic chambers to measure the fractionation Ge and Si in different environments.

为了了解地球气候如何因人为影响（例如化石燃料的燃烧）而发生变化，有必要了解冰期/间冰期气候的自然变化。研究这种变化的一种方法是通过调查深海沉积记录，其中包含过去气候条件的化学、化石和矿物学证据。沉积物中一个潜在的重要信号是蛋白石中的 Ge 与 Si 的比率，该比率会随着海洋条件的变化而变化。为了最大限度地利用该工具，必须充分了解其在海底的化学行为。因此，这项工作将通过实验室实验研究海洋沉积物中 Ge 和 Si 的分馏，从而创建受控的成岩环境，以确定 Ge 和 Si 融入铁氧氢氧化物和硫化物中的情况。 此外，还将分析现有的孔隙水样本，以研究Ge在不同海洋环境中的行为。 将在加利福尼亚州边境进行实地研究，以收集额外的孔隙水并部署原位海底室来测量不同环境中的 Ge 和 Si 的分馏。