Distinct assemblages of landforms are produced by retreating ice streams (e.g. Stokes & Clark 1999; Wellner et al. 2006). The composition of landforms is governed by ice-stream retreat dynamics, implying that ice-stream dynamics can be reconstructed from these geomorphic patterns. This method has been used to decipher the retreat dynamics of an ice stream that occupied the Kveithola Trough on the western Barents Sea margin, presumably during the Late Weichselian deglaciation (Rebesco et al. 2011; Rüther et al. 2012; Bjarnadóttir et al. 2013).
Description
Kveithola Trough contains a diverse assemblage of landforms related to the presence and withdrawal of an ice stream, as well as to postglacial processes (Fig. 1a, b), described in detail by Bjarnadóttir et al. (2013). Here, the acoustic-stratigraphic units defined by Bjarnadóttir et al. (2013) are used, with a focus on seafloor morphology relating to the ice-stream landform assemblage.
Multibeam swath bathymetry from Kveithola Trough, western Barents Sea. (a) Swath-bathymetric image showing trough geomorphology. White polygons indicate locations of detail images (c–f). White lines indicate profiles in Figures 2 and 3. VE×8. (b) Location of study area (red box; map from IBCAO v. 3.0). (c) Oblique view of ice-stream onset zone, showing drumlins and channels. VE×20. (d) Oblique image showing multiple generations of grounding-line fans downstream of a GZW. VE×20. (e) Oblique view of MSGLs on/beneath GZWs. VE×35. (f) Oblique view of diverging MSGLs, shelf edge and gullies on upper slope. VE×16. Images (c–f) are viewed from the black stippled lines. Acquisition system Kongsberg Simrad EM300. Frequency 30 kHz. Grid-cell size 10 m.
Kveithola is on the western margin of the Barents Sea, 40 km NW of Bear Island (Fig. 1b). The trough is c. 90–120 km long, 10–15 km wide (slightly wider at the seaward end) and 200–700 …
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