The Fate of Molybdenum and Its Isotopes in Deep Marine, Oxide-Rich Sediments: Implications for the Mo Isotope Paleoproxy

钼(Mo)同位素有可能作为过去海洋缺氧的示踪剂。然而，为了验证钼作为替代物的应用，有必要更好地了解影响深海沉积物中钼同位素组成的成岩过程。这项研究将研究深水下沉积物中钼和锰与硫、碳和铁的耦合循环，其对钼同位素组成的影响(因此其作为替代指标的有效性)目前尚不清楚。将分析一组现代沉积物样品和相关孔隙水中的常量和微量元素，以研究潜在的钼下沉、成岩途径和释放到上覆海水中的机制。这项工作的结果将对钼作为了解过去海洋状况的工具的可靠性产生重要影响。资金将支持加州大学河滨分校的一名女性初级研究员。阿尔弗雷德·韦格纳研究所的一名德国博士生将参加该项目两个月，以加强国际合作关系。UCR的两名本科生也将接受培训。成果将通过一系列讲座与乌拉圭的行业合作者分享。

Molybdenum (Mo) isotopes have the potential to act as tracers of past ocean anoxia. However, to validate the application of Mo as a proxy, a better understanding of the diagenetic processes affecting its isotopic composition in deep marine sediments is necessary. This research will examine the coupled cycling of Mo and manganese with sulfur, carbon, and iron in sediments underlying deep oxic waters, the effect of which on Mo isotope composition (and thus its validity as a proxy) is currently unknown. Major and trace elements in a set of modern sediment samples and associated pore waters will be analyzed to investigate potential Mo sinks, diagenetic pathways, and mechanisms for release into the overlying seawater. The outcome of this work will have important implications for the reliability of Mo as a tool for understanding past ocean conditions. Funding will support a female beginning investigator at the University of California- Riverside. A German doctoral student from the Alfred Wegner Institute will join the project for two months, strengthening international collaborative ties. Two undergraduates from UCR will also be trained. Results will be shared with industry collaborators in Uruguay through a series of lectures.