Mineral-fluid reactions in metamorphism and carbon sequestration

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This project will assess the role of mineral fluid reactions in modulating fluid flow in Earth's deep crust and in absorbing the greenhouse gas carbon dioxide from the atmosphere. Fluid flow at depth within Earth's crust may control how the crust behaves during mountain building and magmatism. Fluid flow is also essential for the formation of some metallic and high-tech industrial mineral ore deposits, and influences rock behaviour during deformation (e.g., earthquake events). A critical control on fluid flow is the formation and destruction of permeable pathways by mineral reactions and rock deformation. Likewise, mineral reactions can contribute towards the long term sequestration of carbon dioxide from the atmosphere. One promising area of application is in using industrial waste, such as mine tailings, to capture and bind carbon dioxide for millennia, thus contributing to the mitigation of the climate change problem.******This project will determine the mechanisms and rates by which permeable pathways are created and destroyed in specific geologic settings. This will be accomplished by examining rocks from field areas in British Columbia and Oman, and by developing new computer models for fluid flow and reaction at geologic conditions and timescales. These studies will contribute fundamentally to our understanding of the mechanical and chemical coupling of fluid flow, rock deformation, and mineral reaction; processes that are ubiquitous within Earth's crust and are particularly important during ore genesis and seismic events.******We will also examine geologic analogues to mine-based greenhouse gas sequestration operations to better understand the controls and consequences of mineral fluid reactions over long time scales (thousands of years). The value of studying natural analogues is that they allow us to assess the long term stability of stored carbon but also typically yield new insights into processes that have not been observed to operate at laboratory conditions. This project will focus on understanding what controls the precipitation of the mineral magnesite, which forms at low temperature in nature but has to date been nigh impossible to replicate in the lab at room temperature. With insights from studying natural analogs, we will seek to accelerate the formation of magnesite in industrial carbon sequestration systems to yield more efficient and safer carbon storage.**