Mariana Esteves, Denise Christina Rüther, Monica C.W. Winsborrow, Stephen Livingstone, Calvin Shackleton, Karin Andreassen, Wei-Li Hong, Jochen Knies

Drainage of meltwater beneath an ice sheet influences ice-flow dynamics. To better predict ice sheet behaviour, it is crucial to understand subglacial hydrological processes. Subglacial lakes are important components of the subglacial hydrological system, with many observed and predicted at the beds of contemporary and palaeo-ice sheets. The technical and logistical challenges of studying subglacial lakes in Antarctica and Greenland have motivated recent efforts to reliably identify often more accessible palaeo-subglacial lakes, which serve as valuable geological analogues. In this paper, we present a suite of sediment records from an interconnected basin and channel system in the central Barents Sea, inferred to represent a palaeo-subglacial lake system based on glacial geomorphological mapping. We observe clear lithological differences between cores extracted within and outside the basins. Cores from within the basins are characterised by winnowed till or rain-out till overlain by high- to low-energy sediment deposits, consistent with irregular flushing of meltwater followed by ice proximal conditions. We identify varying degrees of hydrological activity between basins, with those well-connected by meltwater channels characterised by winnowed till, while the more marginal basins are associated with thick rain-out till deposits. This work provides the first geomorphological and sedimentological record of a dynamic and active palaeo-subglacial lake system in the central Barents Sea.