Follow the Elements! We look beyond requiring water for life, and try to understand what other elements - including C, N, O, and many metals - play a role in life. Read more.
A collaborative research effort aimed at improving our understanding of ocean redox evolution in the Precambrian. Read more.
We are investigating the hypothesis that metallomic differences among organisms evolved in response to changes in metal availability in ancient oceans. Read more.
Strontium and oxygen isotopes in archaeological human remains can be used to identify migration patterns and, in some cases, the geographic origins of individuals in the past. Read more.
What causes metal stable isotope fractionation? The answer to this question determines how these new isotope systems can be applied. We investigate isotope effects through a combination of field, laboratory and theoretical investigations. For example, we are studying Mo isotope effects in the Baltic Sea, in laboratory adsorption experiments and through computational chemical modelling. Read more.
How do microbes extract metals from minerals? We are exploring the production of metal-chelating organic ligands by desert crust bacteria in a collaboration with the Hartnett and Garcia-Pichel groups at ASU, and Fe and Mo isotope fractionation during microbially-mediated weathering together with Sue Brantley's group at Penn State. Read more.
The environmental chemistry of many metals depends on the availability of O2. Taking advantage of this dependence, we study Mo and Fe concentrations and isotope compositions in ancient sediments for clues about changes in environmental oxygenation. Read more.