A distal record of the erosional unroofing of the Trans-Hudson orogen preserved in the ~1.6 Ga Ellice Formation, Elu basin, Nunavut

Provenance analysis employing detrital zircon geochronology can be used as a tool for understanding paleogeography and sediment dispersal networks. If sediment dispersal networks are broad enough, then they can be used to support regional stratigraphic correlations. The Proterozoic Nuna supercontinent is postulated to have hosted a vast and articulated fluvial network of Amazonian scale across its interior, ca. 1.6 Ga. The late Paleoproterozoic Elu basin, located in the core of Laurentia, is one of the lesser-studied remnants of this sedimentary system, providing a unique opportunity to test the hypothesis of an ancient pancontinental drainage network. Paleocurrent and detrital zircon age data from other remnants of this system suggest that they originated from the Trans-Hudson orogenic uplands, transporting detrital material across Laurentia for thousands of kilometres. We investigate the provenance of fluvial and near-shore marine strata belonging to the Ellice Formation, the main siliciclastic unit of the Elu basin, through the first comprehensive U–Pb geochronologic analysis of detrital zircon therein. During initial fluvial deposition, detritus was primarily derived from local basement and rocks presently preserved to south and east of the basin. Up-section, more distal sources were incorporated as the basin catchment broadened. Comparison with the nearby Hornby Bay and Big Bear basins provides evidence of a connected sediment dispersal network. Our results altogether corroborate the hypothesis of a trans-Laurentia drainage system and refine paleogeographic details regarding its extent.