9405560 Patrick The Brooks Range of Alaska is a major collisional belt that contains a metamorphic core of high pressure/low temperature rocks. It is thought that these blueschist and greenschist facies rocks in the metamorphic core resulted form a mid-Mesozoic collision between a north-facing island arc and an older passive continental margin. The P.I.'s recent work in the area has shown that a proposed major thrust in the schist belt of the Central Brooks Range is in fact a stratigraphic contact and there is evidence to suggest that the bulk deformation was mostly contractional, rather than extensional as proposed by other workers. This project will examine the petrology, structure and geochronology of the transition between the internal metamorphic zone and the external zone of the Brooks Range. It will investigate the links between the internal and external zones and examine the contributions of extension and contraction during the collisional orogenic event. The results of this work will be broadly applicable to all major orogenic belts.
