The Cordillera Darwin complex in southern Chile exposes high grade metamorphic rocks in close proximity to rocks of considerably lower grade across the Beagle Canal. Recent models suggest that the high grade rocks form the core of an extensional "metamorphic core complex" and their exposure was accommodated by large-scale tectonic denudation. This project is a continuation of a petrographic and age dating effort to test this model by assembly of PTt paths and radiometric dating techniques. Data collected so far are consistent with the proposed structural models, but are not sufficiently robust or abundant to unambiguously constrain them. The purpose of this renewal is to document additional PT paths from both high and low grade localities and to collect age data to constrain particularly the early cooling history. Results are expected to place tight constraints on the pressure (depth), temperature and time evolution of this area that will allow a thorough test of the extensional core complex theory.
