Turbiditic sedimentation during syn-orogenic evolution of the Paleoproterozoic Nûkavsak Formation (Karrat Group), West Greenland

The Karrat Group extends hundreds of kilometers along the Rae craton of coastal West Greenland and represents deposition prior to and during Paleoproterozoic orogenic events. The Nûkavsak Formation, the youngest stratigraphic unit of the Karrat Group, preserves sedimentary structures that facilitate the reconstruction of depositional environments, despite tectonic deformation. Here, the sedimentary facies, depositional environments, and tectonic setting of the Nûkavsak Formation are addressed while also considering contextual information from detrital zircon provenance analysis and underlying strata. Our analysis delineates seven lithofacies within the Nûkavsak Formation. The depositional setting reflects variations in water depth, proximity to sediment sources, and tectonic activity. The formation was deposited below storm wave base through cohesive and turbulent sediment gravity flows, debris flows, and hemipelagic sedimentation. Deposition in a retro-arc foreland system explains the overall setting and aligns with sedimentological observations. Defining the stratigraphic architecture and facies analysis of the Nûkavsak Formation highlights similarities and differences with Paleoproterozoic sedimentary successions in eastern Arctic Canada and West Greenland that were deposited within the context of the Rinkian and Trans-Hudson orogens.