Retreat dynamics of marine-based ice sheets: perspectives from diverse high-latitude continental margins
Abstract
Processes occurring at the interface between the ice base and the substrate on which it rests are key to determining ice flow behavior. However, the specific and local scale processes which govern ice flow and margin behavior in a diverse range of marine settings can be highly variable, and their wider significance remains poorly understood. The exposed beds of paleo-ice sheets in formerly glaciated areas are an accessible means of studying past ice flow and ice sheet margin behavior. Ice sheets that expanded onto continental shelves in the Arctic and Antarctica left a record of their glacial dynamics in the form of landforms preserved on the seafloor. We use a large dataset of glacial landforms from a variety of marine-based ice sheets to systematically characterize glacial modes - encompassing ice flow, thermal regime, and retreat style - of each glacial system within the context of landscape type (trough, bank, basin, and fjord) and bed properties (e.g., slope, substrate type). This allows us to test whether certain glacial modes and importantly variability in glacial modes are prevalent in certain topographic and bed settings. We will address questions such as: Does topography control changes in retreat style/magnitude/consistency? Is flow and retreat on/across banks passive or do banks house dynamic ice connected to upstream sources? Are sedimentary landforms (e.g., grounding zone wedges, glacial lineations) always a signature of ice streaming? By analyzing behavior of marine-based ice sheet dynamics without the confines of a geographically limited dataset, we will be able to provide analogs to contemporary marine-based systems and offer hindsight perspective on potential retreat behavior into the future.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.C44A..01S
- Keywords:
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- 0720 Glaciers;
- CRYOSPHEREDE: 0726 Ice sheets;
- CRYOSPHEREDE: 0774 Dynamics;
- CRYOSPHEREDE: 0776 Glaciology;
- CRYOSPHERE