Skip to main content
Article thumbnail
Location of Repository

Formation of mega-scale glacial lineations observed beneath a West Antarctic ice stream

By Edward C. King, Richard C.A. Hindmarsh and C. R. Stokes

Abstract

Most discharge from large ice sheets takes place through fast-flowing ice streams and their speed is strongly modulated by interactions between the ice and the underlying sediments. Seismic surveys and investigations through boreholes have revealed a spatial association between fast ice flow and saturated deformable sediments. Nevertheless, our knowledge of the morphology of the interface between ice and sediments is still limited, resulting in only rudimentary understanding of the basal boundary conditions beneath ice streams and the generation of subglacial bedforms. Here we present radar data from the bed of a West Antarctic ice stream that reveal the presence of mega-scale glacial lineations. We combine these data with previously published seismic data and show that these lineations develop in areas of dilatant deforming till and are part of a dynamic sedimentary system that undergoes significant change by erosion and deposition on decadal timescales. We find that the mega-scale glacial lineations are indistinguishable from those found on beds of palaeo-ice streams, providing conclusive evidence for the hypothesis that highly elongate bedforms are a characteristic of fast-flow regions in ice sheets

Topics: Glaciology, Earth Sciences
Publisher: Macmillan Publishers
Year: 2009
DOI identifier: 10.1038/NGEO581
OAI identifier: oai:nora.nerc.ac.uk:11107
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • https://doi.org/10.1038/NGEO58... (external link)
  • https://doi.org/10.1038/NGEO58... (external link)
  • http://nora.nerc.ac.uk/id/epri... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.