Preservation of Arctic landscapes overridden by cold-based ice sheets |
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Authors: | P. Thompson Davis Jason P. Briner Robert W. Finkel |
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Affiliation: | a Department Natural Sciences, Bentley College, Waltham, MA 02452-4705, USA b Institute of Arctic and Alpine Research and Department of Geological Sciences, University of Colorado, Boulder, CO 80303-0450, USA c Center for Accelerator Mass Spectrometry, L-397 Lawrence Livermore National Laboratory, Livermore, CA 94550, USA |
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Abstract: | For nearly 40 years, a massive, well-preserved glaciomarine delta more than 54,000 years old and ancillary landforms have formed the cornerstone of models positing limited ice-sheet extent in Arctic Canada during the late Wisconsinan. We present exposure ages for large boulders on the delta surface, which coupled with preservation of relict landforms demonstrate that the region was covered by minimally erosive, cold-based ice during the late Wisconsinan. Our data suggest that surficial features commonly used to define the pattern of late Wisconsinan ice movement cannot be used on their own to constrain late Wisconsinan ice-sheet margins in Arctic regions. |
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Keywords: | Baffin Island Glacial erosion Quaternary chronology Cosmogenic nuclide dating Radiocarbon dating |
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