Grant: Research Tools and Instruments

Global tectonics control the cycles of mass transport throughout the Earth driven by fluid-rock interactions in both near-surface environments and deep crust. Fluid-rock interactions directly control the rates of heat and mass transfer, metamorphic reactions, and the formation of mineral deposits in the Earth's crust. Quantification of these processes is difficult because the information is recorded in micron-scale mineral domains that requires specialized analytical equipment and thorough understanding of applicable techniques. Argon dating of potassic minerals is potentially one of the most powerful tools to decipher the timing and rates of such processes operating at temperatures below 500°C (thermochronology). Potassic minerals are ubiquitous in crustal rocks and often associated with crustal-scale shear zones, regions of fluid-rock interaction, and ore deposits. However, the systematics of 40Ar diffusion in such minerals remain largely enigmatic, which limit the application of argon dating and inhibit interpretation of the results. Thus, the requested funds to upgrade the present Excimer thyratron-based laser to an Excimer ATLEX-LR solid state-based laser will be used to explore, through several projects, isotope transport in the rock volume, which is critical for determining the timing of fluid-rock interactions, heat and mass transfer, metamorphic processes, and mineralization in the crust. Results of this research are anticipated to yield both regional and widespread benefits to Canada, such as developing the economic independence of Nunavut through improved access to traditional commodities like carving stone and ensuring Canada's mineral exploration and extraction capabilities are able to excel in a competitive global marketplace. In addition, as the only facility in a tertiary institution in Canada able to perform in-situ argon dating, the new equipment will help train the next generation of thermochronologists.