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A set of multi-channel seismic profiles (~15000 km) acquired by Russia, Norway and Australia has been used to investigate the depositional evolution of the Cosmonaut Sea margin of East Antarctica. We recognize a regional sediment wedge below the upper part of the continental rise. The wedge, herein termed the Cosmonaut Sea Wedge, is positioned stratigraphically underneath the inferred glaciomarine section and extends for at least 1200 km along the continental margin and from 80 to about 250 km seaward or to the north. Lateral variations in the growth pattern of the wedge indicate several overlapping depocentres, which at their distal northern end are flanked by elongated mounded drifts and contourite sheets. The internal stratification of the mounded drift deposits suggests that westward flowing bottom currents reworked the marginal deposits. The action of these currents together with sea-level changes is considered to have controlled the growth of the wedge. We interpret the Cosmonaut Sea Wedge as a composite feature comprising several bottom current reworked fan systems.

Based on a recently acquired dense grid of sub-bottom profiles and ultra-high resolution bathymetry, we have studied the postglacial depositional history of a West Norwegian fjord system. This dataset reveals a history of frequent mass failures taking place from all slopes surrounding the main studied sediment basin. The study also shows that present-day conditions may be subject to future mass wasting, as significant sediment volumes are retained on the basin margins. The overall sediment distribution seems to be largely governed by the underlying bedrock morphologies. Earthquakes are considered to represent the most dominant trigger mechanism in the area.