The West Shetland margin and adjacent deep-water Faroe-Shetland Channel, offshore NW Britain, is a bathymetrically complex continental margin that has been shaped by a multitude of sedimentary processes. The detailed expression of these depositional and erosional processes is revealed on a sea bed image created by using surface picks from 3D seismic data.
Much of the shelf and upper slope is characterised by relict glacigenic features such as morainal ridges and iceberg ploughmarks. On the slope the activity of down slope processes is indicated by the presence of debris flows, linear gullies with base-of-slope fans and sediment slides. These features relate to multiple glaciations over the past 0.5 Ma, but the sedimentary style of the margin was initiated in the early Pliocene.
In the NE of the study area debris flows do not extend to the basin floor and much of the lower slope is comprised of a contourite drift. Within this drift are areas where distinct waves and ridges have formed, reflecting bottom current activity throughout the Neogene, including glacial episodes.
The construction of the slope apron reflects the interdigitation of down-slope and along-slope deposits, both of which have contributed to continental margin progradation.
In the SW of the study area, the basin floor is partly characterised by erosion. Current intensification, combined with active tectonic inversion, has created erosional scarps cut into Paleocene sediments with relief of up to 200 m. These sediments remain exposed at the sea bed through continued winnowing by deep-water currents.