Subaqueous fans formed in marine and lacustrine settings have been reported from Quaternary and more ancient glacier-influenced environments (e.g. Powell 1990; Dowdeswell et al. 2015). Their presence is often taken to imply a palaeo-glacial environment abundant in sediment-rich meltwater, whose load was sourced from glacial erosion and transported in subglacial channels to the ice margin. The sedimentology of these fans sometimes exhibits bedforms indicative of high-energy water-flow, suggesting that rapid drainage events may be important in the formation of some glacier-influenced submarine fans.
Description
A fan-like sedimentary depocentre occurs on the mid-Norwegian shelf on outer Haltenbanken, about 30 km east of the shelf edge in about 300 m of water (Fig. 1a, b). It has an oval- or lobe-shaped form and a relatively smooth surface where it is undisturbed by subsequent reworking. Its longest axis trends WSW–ENE and it has a maximum length of 14 km and a maximum width of 7 km, covering about 70 km2. From bathymetric profiles across the fan, indicating its elevation above the level of the surrounding seafloor (Fig. 1e), a maximum thickness of 30 m and a volume of 1–2 km3 of sediment is inferred, indicating that the fan-like feature makes up a …
