9614649 Baumgartner The aim of this research is to study the effect of spatially heterogeneous and temporally evolving permeability through field and geochemical studies in the Ubehebe Peak contact aureole and to develop a finite element code capable of modeling the basic physical, thermodynamic and transport processes occurring in a typical upper crustal contact aureole. This includes mass and heat transport, reactive tracer transport, metamorphic reactions, reaction enhancement of permeability, and collapse of permeability. The objectives of the proposal are to: (a) complete a geostatistically based data set of stable isotope compositions of carbonates and silicates in the aureole; (b) establish a geostatistically valid major and trace element data base; (c) expand the capabilities of the finite element code to model infiltration driven mixed volatile reactions, porosity and permeability changes due to reaction progress of such reactions; (d) to include in the code simple rheological models to simulate pore collapse due to plastic, brittle, or elastic failure of a rock undergoing reactions. The evolution of porosity, and hence permeability, in such models can be predicted using the fully coupled transport code together with phenomenological equations linking permeability and porosity, reaction progress and porosity, as well as elastic and plastic pore collapse.