Late Plio-Pleistocene evolution of the Eurasian Ice Sheets inferred from sediment input along the northeastern Atlantic continental margin

Abstract

High-latitude marine sediment archives may contain information about the configuration and dynamics of former ice sheets, paleoclimate and the intensity of glacial erosion and uplift in catchment areas. Compiling information on the Late Cenozoic sediment packages along the NE Atlantic continental margin shows that large sediment volumes (c. 982 × 103 km3) were deposited during the Northern Hemisphere Glaciations (NHG), and that significant spatial and temporal variations in sediment input occurred during three distinct NHG Phases. NHG Phase I (2.7–1.5 Ma) was characterized by high sediment input to the trough mouth fan systems offshore Svalbard, suggesting strong glacial erosion and the development of large ice sheets over Svalbard. Comparatively moderate sedimentation and erosion rates are observed along the SW Barents Sea and the Norwegian margins during NHG Phase I. This indicates more restricted ice sheets over Fennoscandia compared to Svalbard, although periods of shelf edge glaciation most likely occurred. The most prominent overall margin development occurred during NHG Phase II (1.5–0.8 Ma), when recurrent large-scale, continental shelf edge, glaciations are suggested for the entire Eurasian Ice Sheets (EurIS). Compared to NHG Phase I, average sedimentation rates are three (91 cm/kyr) and two times higher (20 cm/kyr), respectively, in the Kara-Barents Sea-Svalbard Ice Sheet (KBSIS) region and the Fennoscandian/British-Irish Ice Sheet (FIS/BIIS) region. During NHG Phase III (0.8–0 Ma), sediment input decreases considerably (73%) along the marine margin of the KBSIS, while increasing significantly (62%) from the FIS/BIIS, in comparison to NHG Phase II. These estimates mark a major transition in the evolution of the EurIS, where the submergence below sea level of the Barents Sea region and the initiation of the Norwegian Channel Ice Stream are suggested to be key factors in this change. Furthermore, the submergence of the Barents Sea region affected ocean-atmosphere coupling and circulation which may have had a potential impact on global long-term climate change.