Understanding Glacial Dynamics in the Westwind Trough, Northeast Greenland

• Main Author: Sarkar, Archishman
• Format: Thesis
• Language: unknown
• Published: 2013
• Subjects: East Greenland; Greenland; Ice Sheet
• Online Access: https://epic.awi.de/id/eprint/35952/; https://hdl.handle.net/10013/epic.43878

The Westwind Trough, NE Greenland is the only deep channel connecting the NE Greenland coast to the continental shelf edge and hence is an important region for the movement of the ice sheet and for the draining of the Greenland Ice Sheet. High-resolution multi-beam bathymetry and sediment echosounding acoustic data, from this area and the immediate vicinity, show the presence of many sub-glacial landforms from the outer-middle continental shelf to the shelf edge. This study uses bathymetry and the hull mounded sediment echosounder (PARASOUND) data which was simultaneously collected on FS Polarstern during Expeditions ARK-XI/2(1994), ARK-XIII/3(1997), ARK-XV/2(1999) and ARK-XXIV/3 (2009). The bathymetry data was processed using Caris HIPS software, gridded with a 20m spacing using Fledermaus software and was then projected with ArcGIS 10.2. The PARASOUND data was only available for expeditions ARK-XIII/3 (1997) and ARK-XV/2 (1999). The sediment echosounder data was visualized using SeiSee 2.2 software to analyze the internal sediment structures of the interpreted glacial features from the Bathymetry data. These data sets give us new direct evidence of significant glacial influence on the sea bed at the mid continental shelf to the continental shelf edge during the Late Glacial Maximum. Results from the sediment echosounder, at the shelf edge, show the presence of 10 m of stratified sediment cover with comparatively higher acoustic penetration and the presence of Mega Scale Glacial Lineations on the inner and outer continental shelf which confirms that the NE Greenland ice sheet was drained by paleo-ice streams. This study provides new evidence of end moraines in the outer continental shelf and gives an insight into the glacial sediment dynamics in the continental shelf edge of NE Greenland. However, more data is required to reconstruct the dynamics of the North East Greenland Ice Sheet more accurately.