There are two main thrusts in this broad-based experimental investigation of kinetic phenomena in materials of the Earth's crust and upper mantle: studies of lattice diffusion in minerals and of textural aspects of fluid-bearing and partially-molten rocks. The diffusion studies focus upon intracrystalline transport of key trace elements and radiogenic isotopes (e.g., Pb, Sr, rare earths) in major rock-forming minerals (olivine, pyroxene, garnet), and also upon specific phenomena such as the isotopic (mass) effect on diffusion and diffusion in the near-surface region (i.e., the outermost 10-100 monolayers). The textural studies are aimed at evaluating the importance of interfacial energy minimization in determining the manner in a which a fluid phase is distributed between mineralogically distinct units in close proximity to one another (i.e., fluid "partitioning"), and also at understanding the coarsening behavior of mineral grains in the presence of a small amount of fluid. Ultimately, it is hoped that the diffusion data will place time and temperature constraints on inter-mineral isotopic and trace-element equilibration, and that the textural information will help petrologists and geochemists deduce the nature of fluid- and melt-rock interaction at depth in the Earth.
