Low-temperature Plasticity of Rock-forming Minerals

📖 The Scoop

The rheology of the Earth’s crust and mantle is in part governed by the physical and mechanical properties of feldspar, quartz, calcite, and olivine. Over the past several decades a significant number of experimental studies have been performed on these minerals. Conventional experiments are generally performed at elevated temperatures because much of the viscoplastic deformation of these minerals is accommodated by high-temperature mechanisms. There is, however, evidence of viscoplastic deformation at lower temperatures (T ≤ 0.3Tm) in the uppermost mantle and throughout the crust. Micromechanical experimental techniques, including nanoindentation and micropillar deformation, can be used to achieve plastic deformation at low temperatures. Using these micromechanical techniques, I investigate the low-temperature rheology of feldspar, quartz, calcite, and olivine, and develop flow laws for low-temperature plasticity relevant to deformation in the upper mantle and shear and fault zones in the crust. Additionally, the work in this dissertation shows that nanoindentation and micropillar deformation can be viable and valuable techniques for the rock deformation community.

Genre: No Category (fancy, right?)