Ice streams are fast-flowing zones of an ice sheet bounded to either side by slower-flowing or even stagnant ice (Bentley 1987). Modern ice-stream margins are identified on satellite and aerial imagery by heavily crevassed shear zones up to a few kilometres wide. On one or both sides, at the base of the ice stream, shear-margin moraines may develop (Stokes & Clark 2002). These moraines can be used to assist in locating former ice streams and defining their width. Landforms interpreted as lateral ice-stream shear-margin moraines have been identified on land in the Canadian Arctic and on the north Norwegian continental shelf based on aerial photographs and extensive multibeam bathymetry and seismic profiles, respectively (Dyke & Morris 1988; Stokes & Clark 2002; Ottesen et al. 2005, 2008).
Description
Several sedimentary ridges from both the transition zone between the fjords and continental shelf of northern Norway and from the shelf itself are described (Fig. 1). At the mouth of Tanafjorden beyond the Finnmark coast (Fig. 1f), well-developed glacial lineations parallel to the fjord axis are identified (Fig. 1a). On the eastern side of the fjord mouth and north of …
