The thermal evolution of crust margins involved in collisional processes is an important issue in tectonics, as the thermal and physical modification of the crust through thrust stacking and associated magmatism play an important role in the growth of continents. This project will focus on the piedmont of Maryland, Delaware and Pennsylvania where a continental margin arc developed and subsequently collided with the margin with attendant overthickening by thrust stacking and low pressure, high temperature metamorphism. The work will develop the tectonic chronology of the collisional orogen through high precision U-Pb ages of zircons and monazite from rocks that record the overthickening event and associated magmatism. The duration of the entire orogenic cycle from arc stage through thrust stacking to partial melting can be uniquely determined in the study area, and should provide a benchmark assessment of rates of metamorphic-igneous-tectonic processes in a collisional environment.
