This proposal requests funds to develop analytical techniques for the platinum group elements (Ir, Os, Ru, Rh, Pt, and Pd) in oceanic rocks at ultra-trace (as low as one part per 1012 parts) levels. The ability to make accurate and precise measurements of the platinum group elements in oceanic rocks at the ultra-trace level is critical in order to refine models for mantle evolution, mantle oxidation state, crustal recycling at subduction zones, and other first-order processes. Further progress in this field requires that laboratory techniques be improved to lower the elemental detection limits to, in some cases, below one part in 1012 parts. Recent improvements in instrumentation have made these ultra-trace element measurements possible in principle, but significant refinements such as those proposed by the principal investigator are needed in the associated laboratory techniques in order to make these measurements practical.
