NSF Award
1048393
Understanding the rheology of earth materials over a range of temporal and<br/>spatial scales is a first-order issue in tectonics. Crustal rheology commonly evolves during strain softening and fluid flow in active orogenic systems, but relations between strain rates, hydrolytic weakening, reaction softening, and fluid flux are incompletely understood. <br/><br/>This work in Utah will integrate detailed laser-probe ( about 400 analyses from 100-micron-scale excavations from multiple microstructural settings in deformed clasts, strain shadows, and veins) and step-heating 40Ar/39Ar geochronologic analyses with ongoing microstructural and microgeochemical studies, providing a novel multidisciplinary approach to quantify strain rates and timing relations of fluid-rock interaction. Students involved at all stages of the project will be exposed to leading and possibly transformative research.
