One of the most important, and difficult to quantify, variables in orogenic (mountain-building) processes is time. Whereas we can measure rates of tectonic processes directly in some active tectonic belts today, we have very few constraints on the rates of tectonic processes in the past. The proposed research is designed to produce quantitative comparisons of the relative rates of metamorphism in metamorphic rocks from different tectonic environments. Rates of metamorphism are directly related to rates of heating and rates of tectonic disturbances (e.g. rates of burial and exhumation), so quantification of metamorphic rates will lead directly to the ultimate goal of placing constraints on tectonic processes in ancient orogenic belts. Rates of metamorphism will be quantitatively constrained by detailed analysis of the rates of nucleation and growth of garnet from rocks of the garnet zone. This will be accomplished through statistical methods, image analysis, thermodynamic analysis and kinetic modeling of garnet compositional zoning
