In this work we will build geochemical evolution modules that simultaneously evolve the trace element and isotopic behavior of proposed scenarios for mantle convection and differentiation. These tools will model the geochemical evolution of a wide spectrum of elements and isotopic systems so that one can readily determine if a given scenario is self-consistent across a broad-spectrum of geochemical constraints-only then could a rare-gas modeller readily see that his particular model is inconsistent with Pb,Sr, or Os isotopic constraints on mantle evolution, or vice versa. We will put these modules within a MATLAB-based graphical environment that will be linked to the GERM web-site for broad distribution within the geochemical community as both a research and teaching aid. These tools will also be used by us to explore the implications of a particular family of scenarios ("two-stage melting") that we feel show considerable promise to reconcile current geochemical and geophysical constraints on the large-scale geochemical evolution of the crust and mantle.
