Orogenic unroofing of the Taltson and Thelon orogens depicted through detrital zircon geochronology of the Sosan Group, Great Slave Lake Supergroup (Northwest Territories, Canada)

Abstract

The investigation of sedimentary successions broadly contemporaneous with supercontinent amalgamation is critical to understand sediment dispersal in response to collisional tectonics. The Paleoproterozoic Great Slave Supergroup of the East Arm basin is one of three sedimentary successions located along the margins of the Archean Slave craton. U-Pb detrital zircon geochronology with chemical-abrasion laser-ablation inductively-coupled plasma mass spectrometry is employed here to investigate the onset of sedimentation, provenance, and regional correlations of the Sosan Group (the Great Slave Supergroup’s basal succession). Although a detrital age signature of the Slave craton is found in the < 1.97–1.95 Ga Hornby Channel Formation (lowermost Sosan Group) – the dominant component through the strata has a distinct ∼ 2.0–1.97 Ga detrital age population, suggesting that the Sosan Group sediments were derived from the collapsing Thelon-Taltson orogenic topography. Data presented herein support novel correlations in the region, specifically between the East Arm basin and the nearby Kilohigok basin, Coronation margin and Hottah terrane. By these means, this study highlights the importance of stratigraphically complete geochronological analyses to propose regional correlations.