Skip to Main Content
Skip Nav Destination

The Ellsworth subglacial highlands; inception and retreat of the West Antarctic ice sheet

Neil Ross, Tom A. Jordan, Robert G. Bingham, Hugh F. J. Corr, Fausto Ferraccioli, Anne Le Brocq, David M. Rippin, Andrew P. Wright and Martin J. Siegert
The Ellsworth subglacial highlands; inception and retreat of the West Antarctic ice sheet
Geological Society of America Bulletin (September 2013) 126 (1-2): 3-15


Antarctic subglacial highlands are where the Antarctic ice sheets first developed and the "pinning points" where retreat phases of the marine-based sectors of the ice sheet are impeded. Due to low ice velocities and limited present-day change in the ice-sheet interior, West Antarctic subglacial highlands have been overlooked for detailed study. These regions have considerable potential, however, for establishing the locations from which the West Antarctic Ice Sheet originated and grew, and its likely response to warming climates. Here, we characterize the subglacial morphology of the Ellsworth subglacial highlands, West Antarctica, from ground-based and aerogeophysical radio-echo sounding (RES) surveys and the Moderate-Resolution Imaging Spectroradiometer (MODIS) mosaic of Antarctica. We document well-preserved classic landforms associated with restricted, dynamic, marine-proximal alpine glaciation, with hanging tributary valleys feeding a significant overdeepened trough (the Ellsworth Trough) cut by valley (tidewater) glaciers. Fjord-mouth threshold bars down-ice of two overdeepenings define both the northwest and southeast termini of paleo-outlet glaciers, which cut and occupied the Ellsworth Trough. Satellite imagery reveals numerous other glaciated valleys, terminating at the edge of deep former marine basins (e.g., Bentley subglacial trench), throughout the Ellsworth subglacial highlands. These geomorphic data can be used to reconstruct the glaciology of the ice masses that formed the proto West Antarctic Ice Sheet. The landscape predates the present ice sheet and was formed by a small dynamic ice field(s), similar to those of the present-day Antarctic Peninsula, at times when the marine sections of the West Antarctic Ice Sheet were absent. The Ellsworth subglacial highlands represent a major seeding center of the paleo West Antarctic Ice Sheet, and its margins represent the pinning point at which future retreat of the marine-based West Antarctic Ice Sheet would be arrested.

ISSN: 0016-7606
EISSN: 1943-2674
Serial Title: Geological Society of America Bulletin
Serial Volume: 126
Serial Issue: 1-2
Title: The Ellsworth subglacial highlands; inception and retreat of the West Antarctic ice sheet
Affiliation: Newcastle University, School of Geography, Politics and Sociology, Newcastle upon Tyne, United Kingdom
Pages: 3-15
Published: 20130919
Text Language: English
Publisher: Geological Society of America (GSA), Boulder, CO, United States
Number of pages: 13
References: 65
Accession Number: 2013-080189
Categories: GeomorphologyApplied geophysics
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. sect., sketch maps
S83°00'00" - S79°00'00", W100°00'00" - W80°00'00"
Secondary Affiliation: British Antarctic Survey, GBR, United KingdomUniversity of Edinburgh, GBR, United KingdomUniversity of Exeter, GBR, United KingdomUniversity of York, GBR, United KingdomUniversity of Bristol, GBR, United Kingdom
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2022, American Geosciences Institute. Reference includes data from GeoScienceWorld, Alexandria, VA, United States. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States
Update Code: 201347
Close Modal

or Create an Account

Close Modal
Close Modal