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Ice sheets reshape Earth’s surface. Maps of the landscape formed by past ice sheets are our best tool for reconstructing historic ice sheet behavior. But models of glacier erosion and deposition that explain mapped features are relatively untested, and without observations of landforms developing in situ, postglacial landscapes can provide only qualitative insight into past ice sheet conditions. Here we present the first swath radar data collected in Antarctica, demonstrating the ability of swath radar technology to map the subglacial environment of Thwaites Glacier (West Antarctica) at comparable resolutions to digital elevation models of deglaciated terrain. Incompatibility between measured bedform orientation and predicted subglacial water pathways indicates that ice, not water, is the primary actor in initiating bedform development at Thwaites Glacier. These data show no clear relationship between morphology and glacier speed, a weak relationship between morphology and basal shear stress, and highlight a likely role for preexisting geology in glacial bedform shape.
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Results from: Geophysical evidence of tectonic structures beneath Thwaites Glacier, West Antarctica: influence on glacier dynamics
Results from seismic travel time inversion and potential fields modeling in: Geophysical evidence of tectonic structures beneath Thwaites Glacier, West Antarctica: influence on glacier dynamics
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- Award ID(s):
- 2001714
- PAR ID:
- 10648102
- Publisher / Repository:
- Zenodo
- Date Published:
- Edition / Version:
- 1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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