Pure and applied problems in metamorphic petrology

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Metamorphic petrology is concerned with changes in the mineralogy and textures of rocks in response to burial and heating in the Earth's lithosphere. It helps Earth scientists understand the thermal evolution of the Earth from 4 billion years ago to the present, understand ancient mountain building and other plate tectonic processes, decipher ore deposits that have been formed or modified by metamorphism, and account for geophysical anomalies in the unexposed lithosphere. The long range objectives of my research are two-fold: (1) to improve the specialized 'tools of the trade' of metamorphic petrology, in particular the techniques and understanding of what controls metamorphic mineral development; and (2) to bring these tools to bear on broader problems in Earth Science. The pure metamorphic petrology aims include: (1-1) improving the match between thermodynamically predicted mineral assemblages and their occurrence in nature; and (1-2) investigating the interplay between equilibrium, kinetics and rock deformation in metamorphism, with implications for the interpretation of metamorphic mineralogy and textures. This improved knowledge will be used to decipher mountain building (orogenic) events in the Canadian Cordillera and other orogenic belts, including: (2-1) discerning the character, timing and interface of contrasting domains of metamorphism in southeastern BC, with implications for the geological evolution of the Cordilleran margin from the time of its inception through to the cessation of orogenesis; (2-2) characterizing the contrasting metamorphic histories across select Eocene extensional faults in southeastern British Columbia, with implications for fault magnitude and deep crustal processes during orogenesis; and (2-3) searching for the extent and nature of newly-recognized post-tectonic metamorphism in the Rocky Mountains, with implications for local ore deposits. Techniques that will be applied include: field work; structural analysis; petrography; rock and mineral chemical/isotopic analysis; phase equilibrium calculations; and kinetic and thermal modeling. Participation of undergraduates, graduate students and post-doctoral fellows is essential to the success of the proposed work.