RESEARCH INTERESTS

Transition metals like iron (Fe), copper (Cu), zinc (Zn), nickel (Ni), and molybdenum (Mo) are intimately linked with (bio)geochemical processes.  We can use their unique chemical behaviours to learn about an expansive variety of topics from the formation of our solar system, to the evolution of life on Earth, to even detecting and treating diseases.

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​The transition metals have two key aspects that make them particularly attractive to Earth scientists: first, by limiting primary productivity, their availability to the biosphere can control the carbon cycle, and secondly, they are sensitive to environmental redox conditions. Therefore, their abundances and isotopic signatures, which can be preserved in the rock record, can trace the evolution of the geo-biosphere and the oxygenation of the ocean and atmosphere.

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However, before we can use these tools to probe Earth history, we must a thorough understanding their modern biogechemical cycling.

​Traditionally, research on the transition metals and their isotopes has focused on the dissolved phase of rivers and oceans.  It was noted even in early work, however, that the particulate load of these elements can dominate the dissolved load and that some portion of this particulate load may be chemically labile and available for use by biology. 

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Addressing the extent to which trace metals in particulate matter may be exchangeable with the dissolved phase has been the focus of my work and is becoming an increasing concern to researchers in the areas of oceanographic, terrestrial, and aerosol biogeochemistry.