9404578 Ferry The proposed research will evaluate how the amount and geometry of fluid flow affect the mineralogical, chemical, and isotopic evolution of regional and contact metamorphic rocks. It includes the study of siliceous dolomites in six contact aureoles in a variety of geologic settings in the United States, Scotland, and Italy. For each aureole the spatial distribution of mineral assemblages and O- and C- isotope compositions will be mapped. Simple models grounded in transport theory will be developed for each aureole to predict mineral assemblages and isotopic compositions at each point along sample traverses as a function of fluid amount. Comparison of observation with prediction will lead to an understanding of both intra-aureole and inter-aureole variability in flow. Coupling of these results with tectonic setting may also lead to generalizations about the control of depth, lithology, and structure on the amount and geometry of flow.
