Physical Sciences and Mathematics Commons^™

Slab Window Migration And Terrane Accretion Preserved By Low‐Temperature Thermochronology Of A Magmatic Arc, Northern Antarctic Peninsula, William Guenthner, David Barbeau, Peter Reiners, Stuart Thomson

David L Barbeau Jr

Existing paleogeographic reconstructions indicate that the northern Antarctic Peninsula was central to several Mesozoic and Cenozoic tectonic events that have implications for ocean circulation and continental margin evolution. To evaluate the exhumational record of these processes, we collected new samples and measured fission track and (U‐Th)/He cooling ages of apatite and zircon from 13 Jurassic and Cretaceous granitoids in western Graham Land between the northern tip of the peninsula and the Antarctic Circle. Apatite He data reveal distinct ages and systematic age patterns north and south of Anvers Island, near the midpoint of the study area: To the south, apatite …