Grant: Discovery Grants Program - Individual

In modern mountain belts it is sometimes difficult to gain an understanding of the processes that work deep in the crust. Exposed roots of old mountain belts, however, consist of rocks that experienced great physical forces of mountain building: pressure, temperature, and stress. Our ability to decipher this record from modeling the composition of minerals in rocks has greatly increased. Add to this the ability to determine the absolute time of mineral formation and the four-dimensional picture of mountain building can be constructed. This research program will investigate our ability to 1) constrain the pressures and temperatures at which particular rock types recrystallized at depth in the earth, and 2) constrain the depths and temperatures at which rocks were buried, partially melted, and began their exhumation path back towards the surface of the earth. Detailed thermodynamic modeling of rocks derived from sediment that was originally deposited in an oceanic or near-continental margin setting will be used to decipher the pressure and temperature changes these rocks experienced during the tectonic evolution of the Superior Province in western Ontario. Minerals will be dated using Sm-Nd and U-Pb geochronology to constrain the timing of burial and exhumation of these rocks. Together, this data will allow us to discover the tectonic processes that led to the construction and stabilization of the crust approximately 2.7 billion years ago in western Ontario. The novelty of this research lies in the integration of thermodynamic modeling of individual rock systems with geochronology to constrain the complicated history of metamorphism experienced by Archean rocks of the western Superior Province.