ARCHEAN MAGMATISM AND METAMORPHISM OF EASTERN HALL PENINSULA, BAFFIN ISLAND: IMPLICATIONS OF REGIONAL CRUSTAL CORRELATIONS USING U-PB GEOCHRONOLOGY

The Northern Labrador – Baffin Island segment of the Trans-Hudson orogen is composed of several distinctly unique crustal components that assembled during a period of tectonic agglomeration from 1.88 to 1.80 Ga. The geologic history of the Archean rocks that dominate the eastern portion of Hall Peninsula remains enigmatic in terms of what crustal block, if any, these rocks were part of prior to the Paleoproterozoic accretionary tectonism. The Archean rocks of Hall Peninsula are yet to be unequivocally correlated with the Rae craton of northern Baffin Island and northern west Greenland, the Meta Incognita microcontinent in southern Baffin Island, the Torngat orogen of Northern Labrador or the Aasiaat domain of west-central Greenland. Similar to these surrounding Archean cratons, the Archean rocks of Hall Peninsula are generally orthogneisses and migmatites that are polymetamorphosed and polydeformed ranging in composition from tonalitic to syenogranitic. New U-Pb dates using the Sensitive High Resolution Ion MicroProbe on zircon grains from 7 distinct units within a small study area on eastern Hall Peninsula brackets Archean magmatism from ~2.99 to 2.72 Ga with evidence of previously undocumented Archean metamorphism at ~2.71 Ga. These dates overlap with those obtained for similar orthogneisses in the Disko Bugt region of central west Greenland, which is ascribed to the North Atlantic craton. In addition, crustal correlations between Hall Peninsula and the Torngat orogen of Northern Labrador, which is also part of the North Atlantic craton, cannot be ruled out and may in fact not be mutually exclusive with the correlations to central west Greenland.