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This dataset contains the basal ice unit thickness as measured by the NSF COLDEX MARFA ice-penetrating radar survey, which mainly focuses on the southern flank of Dome A. The "basal ice unit" is hereby defined as the bottom portion of the ice sheet where no clear and traceable englacial reflection is detected by the radar sounder. Raw radar data can be found at: https://doi.org/10.15784/601768. The basal ice unit is mapped using the DecisionSpace Geosciences 10ep software package. This dataset provides three data products: • Thickness of the basal ice unit • Thickness of the stratigraphic ice unit above the basal ice unit • The shape of the basal ice unit boundary, where rapid basal ice unit thinning is observed in the middle of the South Pole Basin.
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Coupled Ice Sheet Structure and Bedrock Geology in the Deep Interior of East Antarctica: Results From Dome A and the South Pole Basin
The deep interior of the East Antarctic Ice sheet likely contains important records of climate and ice sheet evolution. Here we report on a recent aerogeophysical survey of the southern flank of Dome A, over South Pole Basin. We find an extensive radioglaciologically defined basal unit under Dome A that abruptly truncates within South Pole Basin. This truncation aligns with a change of subglacial bed properties and distinct subglacial landforms. We infer that this basal unit may be slowly transporting and depositing material through local basal melting in South Pole Basin into an extensive, subglacially forming, sedimentary basin. In turn, this sedimentary basin may induce locally enhanced melting by hosting local groundwater.
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- Award ID(s):
- 2127606
- PAR ID:
- 10656789
- Publisher / Repository:
- American Geophysical Union/Wiley
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 52
- Issue:
- 19
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Associated Dataset(s):
- View Associated Dataset(s) >>
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1029/2025GL115729
