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.