Trough-mouth fans (TMFs; e.g. Vorren et al. 1989) are seaward-convex sedimentary depocentres composed of alternating prograding and aggrading sequences derived primarily from the accumulation of glacigenic debris-flows. In addition, sedimentation may come from contour currents, settling from subglacial meltwater plumes (Taylor et al. 2002) and repeated events of sediment mass transport (Hjelstuen et al. 2007). Ice streams hosted in the glacial troughs are the main mechanism of glacial sediment erosion and transport to the shelf edge during lowstands of sea level at glacial maxima. Glacigenic debris-flow deposition is focused at the front of glacial troughs (e.g. Laberg & Vorren 1995, 1996).
Description
The Storfjorden TMF (Fig. 1a) shows a seaward-convex depocentre described by Pedrosa et al. (2011) and Lucchi et al. (2013). The overall bathymetry shows that the outer part of Storfjorden Trough comprises three large depressions separated by shallower banks (Fig. 1a). The continental shelf edge defines three broad lobes, …
