Glacial retreats in the Barents Sea: implications for gas hydrates formation

The recent depositional architecture of the north-western Barents Sea continental margin derives from past climate changes with alternating deposition of highly consolidated glacigenic diamicton associated to shelf-edge glaciations, and low-density, normally consolidated biogenic-rich sediments deposited during interglacial conditions. In addition, sub-bottom records outline the presence of acoustically laminated deposits locally having thickness exceeding 10 m, which lithofacies characteristics indicate deposition from turbid meltwaters (plumites) during short-living, phases of glacial retreat (meltwater pulses, MWP). One of the youngest stratigraphic intervals recognized along the NW Barents Sea margin was related to the MWP-1a (Lucchi et al., 2013, 2015) responsible for the most abrupt sea level rise after Last Glacial Maximum (LGM). Recent investigations in the Kveithola glacigenic system focused on time reconstruction of the ice stream retreat after LGM, revealed the presence of a complex depositional system with glacially related bottom features (e.g. mega-scale glacial lineations and grounding zone wedges) overimposed by recent contour currents related deposition. Here, evidences of ongoing seepages activity with potential seasonal gas hydrate formation, suggest a possible last glacial ice sheet interaction with basal gas hydrate formation that delayed the local ice sheet retreat.