Submarine gullies and an axial channel in glacier-influenced Courtauld Fjord, East Greenland

Abstract

Submarine gullies have been observed widely in swath-bathymetric imagery of the shelf edge and upper slope on high-latitude margins (e.g. Noormets et al. 2009; Gales et al. 2013), but less frequently in fjords. Gullies vary in distribution and dimensions depending on formation mechanisms, including submarine mass wasting, subglacially or proglacially derived turbid underflows and dense bottom-water currents linked to brine rejection during sea-ice formation (e.g. Noormets et al. 2009). Since recession of the Greenland Ice Sheet through Kangerlugssuaq Fjord (68° N) in East Greenland after the Last Glacial Maximum (Dowdeswell et al. 2010), significant seafloor erosion on the flanks of the inner tributary fjords has taken place to produce a series of submarine gullies and an axial channel (Fig. 1a–e). Fig. 1. Multibeam bathymetry and cross-profiles of submarine gullies in Courtauld Fjord, East Greenland. ( a ) Submarine gullies in the outer fjord and subglacial bedforms in the inner fjord. Courtauld Glacier drains into the head of the fjord and several glaciers are also present along the east flank of the fjord. Dashed white line and white arrows mark the lateral moraine on the western fjord wall produced when Courtauld Glacier last advanced to the outer fjord sill during the Little Ice …