Impact of Paleocene–Eocene tectonic and climatic forcing on Arctic sediment transfer variability: SW Barents Sea, Norway

Abstract

During the Paleocene and Eocene, many Arctic basins experienced multiple, yet synchronous periods of increased sedimentation rates. Several causal factors have been suggested including major volcanic events, tectonic plate reorganization and plate break-up, as well as widespread uplift along with contemporaneous and short-lived hyperthermal events. However, the significance of and relation between tectonic and climatic forcing on Arctic sediment transfer during the early Paleogene are poorly understood. In this case study from the Barents Shelf margin in the Norwegian Arctic, we present previously unpublished cores combined with exploration wells, and new high-resolution 3D seismic data to investigate sedimentary stacking patterns and geomorphological features in the Sørvestsnaget Basin. Our integrated investigations reveal the development of climate-controlled and tectonically-driven submarine fans. The PETM fans display an individual fan as a result of single depositional event compared to the middle Eocene fans that show stacked submarine fans probably deposited during multi-phase events. Our stratigraphic forward modelling analysis indicates that regional-scale tectonically induced uplift significantly increased the amount of sand delivered to the basin as documented by a thickening of the basin fill succession. The climatic component contributes to sand transport variability to the basin, and thus the temporal evolution pattern of sand is much varied. Finally, we discuss our findings with the tectonic and climatic forcing factors in a circum-Arctic perspective.