Browse by author
Lookup NU author(s): Professor Neil RossORCiD
This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
Antarctic bed topography influences how the overlying ice sheet responds to climate change and provides a record of long-term glacial history. However, knowledge of the processes that governed the development of the landscape before glacial inception and how this modulated subsequent ice-sheet evolution remains limited. Here we use radio-echo sounding to reveal extensive flat surfaces beneath the ice margin between Princess Elizabeth Land and George V Land, East Antarctica. When their elevations are isostatically adjusted for unloading of the present-day ice load, these surfaces cluster at 200–450 metres above sea level and dip gently in an offshore direction. We show that the surfaces are fragments of a once-contiguous coastal plain formed by fluvial erosion, which dates from between the separation of East Antarctica from Australia (~100–80 Ma) and the onset of Southern Hemisphere ice-sheet glaciation (~34 Ma). The preservation of these landforms indicates a lack of intense, selective erosion of the surfaces throughout Antarctica’s glacial history. Fast-flowing ice has instead been directed through inherited tectonic structures and fluvial valleys, leading to the incision of overdeepened subglacial troughs between the flat surfaces and thus modulating the responsiveness of the ice sheet to climate change.
Author(s): Paxman GJG, Jamieson SSR, Ross N, Bentley MJ, Carter CM, Jordan TA, Cui X, Lang S, Sugden DE, Siegert MJ
Publication type: Article
Publication status: Published
Journal: Nature Geoscience
Year: 2025
Volume: 18
Pages: 724–731
Print publication date: 01/08/2025
Online publication date: 11/07/2025
Acceptance date: 30/05/2025
Date deposited: 11/07/2025
ISSN (print): 1752-0894
ISSN (electronic): 1752-0908
Publisher: Nature Publishing Group
URL: https://doi.org/10.1038/s41561-025-01734-z
DOI: 10.1038/s41561-025-01734-z
Data Access Statement: The radio-echo sounding bed pick data used in this study are available via WISE-ISODYN23 , ICECAP67,68 , CHINARE69 and OIB70 . Other geospatial datasets used in this study are available via BedMachine Antarctica 71 , MEaSUREs Antarctic ice velocity 72 , isostatic response to ice-sheet unloading73 , Copernicus Global 90 m digital elevation model62 , basal thermal state derived from RES74 and ISSM basal thermal state output75 . The Copernicus/ESA Sentinel-2b images shown in Extended Data Fig. 4 were acquired free of charge from the Copernicus Open Access Hub (https://scihub.copernicus.eu/). The datasets generated as part of this study, including the database of East Antarctic flat surfaces, are avail- able via Zenodo at https://doi.org/10.5281/ZENODO.11367659 (ref. 76).
Altmetrics provided by Altmetric
