Grant: Discovery Grants Program - Individual

Understanding mountain building events requires determination of the changes in temperature and pressure that rocks experienced during those events, and in particular requires determination of the rates of vertical movement during those processes. A variety of techniques can be used to determine these changes in pressure and temperature, including the rates of these changes. The proposed research will combine geological mapping, studies of rock textures, analysis of the chemical compositions of minerals and rocks, and thermodynamic data to model the development of mineral assemblages, modes, and compositions. Comparison of measured values with model values allows determination of the pressure and temperature at which the mineral assemblage developed and how these values changed with time. The combination of this data with the radiogenic isotopic composition of minerals and rocks allows the timing of these changes to be calculated. The combination of the pressure, temperature, and time of formation of rocks leads to a better understanding of the nature and rates of mountain building processes. This study is specifically designed to use modern thermodynamic modelling techniques on an important group of rocks to determine the pressure, temperature, and time of rock formation, and to determine the chemical reactions that lead to partial melting of these rocks. In addition, the study will document how to thermodynamically model a particular class of rocks that have not been extensively modelled in the past, and will also document inadequacies in our current ability to model such rocks and identify future avenues of research to help overcome these inadequacies. This will results in an enhanced ability to use this class of rocks to determine the pressure-temperature-time history of mountain-building events.