I am motivated by several aspects of how the earth functions. Primarily, my research attempts to gain information about geochemical processes at a range of scales and apply that understanding to new applications across the bio-, hydro-, and geospheres. I am interested in elemental redistribution and isotopic fractionation of non-traditional stable isotopes and heavy metals and how those geochemical changes can inform our understanding of large-scale earth processes.

As director of the Metal Isotopes Laboratory at Indiana University, I analyze trace metals and non-traditional stable isotopes in various earth materials. This work focuses on two primary themes:

1. Geochemical changes of heavy metals related to large-scale geologic processes. 

By utilizing a suite of heavy metals and non-traditional stable isotopes in conjunction with one another, we aim to directly measure and analyze controls on geochemical changes and their implications during subduction, metasomatism, ore genesis, hydrothermal alteration, and crustal recycling. This work seeks to answer questions such as: 

• • Do these processes impart a distinct geochemical signature on geologic materials?
  • If so, are there other controls affecting the geochemistry of these rocks, such as mineralogical variations or fluid fluxing?
  • Do multiple isotopic systems provide a consistent picture of elemental mobility and fractionation or do they provide a deeper insight into Earth processes?

Many heavy metals are transferred from geologic material into the biosphere via uptake in plant material, which then enters into the food chain. While this can pose significant health threats in certain environments, it also provides new opportunities for understanding biologic transformations of contaminants, biogeoprospecting of ore material associated with certain heavy metals, and long-term passive monitoring of affected areas. As such, this work attempts to answer questions such as:

• • Do biologic processes, such as plant uptake, alter the geochemical signatures of heavy metals found in the underlying rock material?
  • Are any biologically-imparted variations consistent among plant or substrate type?
  • For redox-sensitive elements, do microbial interactions play any part in altering biogeochemical signatures?