Experimental investigation of the fractionation of Non-traditional stable isotopes by planetary processes

Chemical and physical processes can fractionate the isotopic ratios of elements that have more than one isotope. Studying the isotopic ratios of a few light elements, notably H, C, O or S, has long occupied a central role in geochemistry, but until a decade or so ago, isotopic fractionation of heavier elements, such as the first-row transition metals, was thought to be too small to measure usefully. Now advances in analytical techniques are revealing ubiquitous isotopic differences in such elements as Fe, Cr, V, Cu, Zn, Ni and Mo at resolvable levels in geomaterials. Understanding what causes such variations requires experimental investigation. The reward will be new tests for many geological hypotheses.