This award is for support of research in the following areas: 1) Partitioning and distribution characteristics of the platinum- group elements in synthetic melts and crystals as a function of fO2 and fS2; 2) further development of Re-Os dating using high efficiency ionization sources and the application of these procedures to mantle and crustal rocks and minerals; 3) The study of trace element distributions in crystal-melt equilibrium, in zoned crystals, in conjunction with crystal-chemical models; 4) The chemical-petrographic and isotopic study of submicroscopic inclusions in diamonds to determine the nature and age of trapped mantle fluids and the correlation of potassic inclusions with carbonate and water contents; 5) The study of the concentration and distribution of large ion, lithophile elements in ultramafics and the isotopic composition of Sr, Nd and Pb; 6) The study of U- series disequilibrium and Th232/U238 ratios in fresh basic and ultrabasic rocks using mass-spectrometric methods; 7) determination of the CO2 solubility in synthetic silicate melts and in recent glasses; and 8) The investigation of theoretical models to explain both Nd and Sr isotopic patterns and trace element abundances in rocks which represent mixed magma sources. Much of the funding will go for graduate student support, including the travel and supplies they will need.
