The geomorphic and sedimentary record of glaciation on high-latitude continental margins with particular reference to the northeastern Svalbard margin

• Main Author: Hogan, K. A.
• Published: University of Cambridge 2009
• Subjects: 551.4
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604144

A comprehensive geophysical survey dataset from the continental shelf of northeastern Svalbard is analysed for the first time in order to investigate the seafloor geomorphic and sedimentary records of glaciation in the area, and to interpret this information in the context of large-scale ice sheet development. High-resolution swath-bathymetric data, used together with co-located 3.5 kHz sub-bottom profiler records and geological core records, are used to characterise and map submarine glacigenic landforms. Process-based interpretations are used to group these data into landsystem models, which are then used to reconstruct former ice-sheet behaviour and dynamics during the Late Weichselian (30-10 kyr B.P.). Absolute flow directions suggest that flow was towards the east and northeast in areas south of the Kvitøya Trough, and northwards towards the shelf break in the trough itself. On the basis of these data, new ice-sheet reconstructions are presented for this sector of the former Svalbard-Barents Sea Ice Sheet and include the suggestion that the former ice centre was located significantly further west than in previous reconstructions. A fast-flowing Kvitøya Trough ice stream draining a significant internal ice basin did not exist. Two further datasets are considered. First, a TOBI side-scan sonar dataset collected over the Hinlopen Slide scar provides detailed imagery of this grant submarine slope failure, which is located in a glacier-influenced, outer shelf setting. Through a systematic analysis of meso-scale morphological features (m to km scale) new insights into the composition of slide scarps and deposits are gained and small-scale post-slide processes are identified. Lastly, a 3D seismic dataset from the Murzuq Basin, Libya, which images an ancient (~440 Myr B.P., Late Ordovician) glacigenic succession, is also analysed. By considering the architecture of the deposits and their glaciological setting in an inner shelf, inter-ice stream area, modern analogues for the glacier-related sediments are identified.