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Abstract Knowledge of Antarctica's sedimentary basins builds our understanding of the coupled evolution of tectonics, ice, ocean, and climate. Sedimentary basins have properties distinct from basement‐dominated regions that impact ice‐sheet dynamics, potentially influencing future ice‐sheet change. Despite their importance, our knowledge of Antarctic sedimentary basins is restricted. Remoteness, the harsh environment, the overlying ice sheet, ice shelves, and sea ice all make fieldwork challenging. Nonetheless, in the past decade the geophysics community has made great progress in internationally coordinated data collection and compilation with parallel advances in data processing and analysis supporting a new insight into Antarctica's subglacial environment. Here, we summarize recent progress in understanding Antarctica's sedimentary basins. We review advances in the technical capability of radar, potential fields, seismic, and electromagnetic techniques to detect and characterize basins beneath ice and advances in integrated multi‐data interpretation including machine‐learning approaches. These new capabilities permit a continent‐wide mapping of Antarctica's sedimentary basins and their characteristics, aiding definition of the tectonic development of the continent. Crucially, Antarctica's sedimentary basins interact with the overlying ice sheet through dynamic feedbacks that have the potential to contribute to rapid ice‐sheet change. Looking ahead, future research directions include techniques to increase data coverage within logistical constraints, and resolving major knowledge gaps, including insufficient sampling of the ice‐sheet bed and poor definition of subglacial basin structure and stratigraphy. Translating the knowledge of sedimentary basin processes into ice‐sheet modeling studies is critical to underpin better capacity to predict future change.
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Basement Topography and Sediment Thickness Beneath Antarctica's Ross Ice Shelf
Abstract New geophysical data from Antarctica's Ross Embayment reveal the structure and subglacial geology of extended continental crust beneath the Ross Ice Shelf. We use airborne magnetic data from the ROSETTA‐Ice Project to locate the contact between magnetic basement and overlying sediments. We delineate a broad, segmented basement high with thin (0–500m) non‐magnetic sedimentary cover which trends northward into the Ross Sea's Central High. Before subsiding in the Oligocene, this feature likely facilitated early glaciation in the region and subsequently acted as a pinning point and ice flow divide. Flanking the high are wide sedimentary basins, up to 3700m deep, which parallel the Ross Sea basins and likely formed during Cretaceous‐Neogene intracontinental extension. NW‐SE basins beneath the Siple Coast grounding zone, by contrast, are narrow, deep, and elongate. They suggest tectonic divergence upon active faults that may localize geothermal heat and/or groundwater flow, both important components of the subglacial system.
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- Award ID(s):
- 1443497
- PAR ID:
- 10369725
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 49
- Issue:
- 10
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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