My current research interest is in heavy stable isotope geochemistry. This field is a new and rapidly evolving field with new elements and new fields of application accumulating rapidly. Experimental data are of fundamental importance in order to provide a framework for the interpretation of this new and exciting data. In addition to biological processes, adsorption processes at the particle-water interface appear to play a major role in the fractionation of heavy element isotopes in a wide range of environments (e.g. natural waters, industrial waste waters, soils and sediments) suggesting applications in a wide range of fields (e.g. enviromental geochemistry, oceanography, geomicrobiology).

I have been involved in the investigation of the natural variation in the isotopic composition of Mo and the experimental investigation of natural processes capable of fractionating Mo. This work is aimed at understanding the Mo cycle in the oceans and developing the potential use of the Mo isotope composition of marine sediments (in particular black shales) to track variations in global oceanic anoxia through time. I have also been involved in a collaborative studies of microbially mediated fractionation of Mo and Fe extracted from silicates.

Currently I am interested in the development of potential applications for Cd, Zn, Cu, Li and Fe isotopes.