TY - JOUR
T1 - Water pressure fluctuations control variability in sediment flux and slip dynamics beneath glaciers and ice streams
AU - Damsgaard, Anders
AU - Goren, Liran
AU - Suckale, Jenny
N1 - Funding Information:
This research was supported by the National Science Foundation through the Office of Polar Programs awards PLR-1744758 and by the U. S. Army Research Laboratory under grant W911NF-12-R0012-04.
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/18
Y1 - 2020/12/18
N2 - Rapid ice loss is facilitated by sliding over beds consisting of reworked sediments and erosional products, commonly referred to as till. The dynamic interplay between ice and till reshapes the bed, creating landforms preserved from past glaciations. Leveraging the imprint left by past glaciations as constraints for projecting future deglaciation is hindered by our incomplete understanding of evolving basal slip. Here, we develop a continuum model of water-saturated, cohesive till to quantify the interplay between meltwater percolation and till mobilization that governs changes in the depth of basal slip under fast-moving ice. Our model explains the puzzling variability of observed slip depths by relating localized till deformation to perturbations in pore-water pressure. It demonstrates that variable slip depth is an inherent property of the ice-meltwater-till system, which could help understand why some paleo-landforms like grounding-zone wedges appear to have formed quickly relative to current till-transport rates.
AB - Rapid ice loss is facilitated by sliding over beds consisting of reworked sediments and erosional products, commonly referred to as till. The dynamic interplay between ice and till reshapes the bed, creating landforms preserved from past glaciations. Leveraging the imprint left by past glaciations as constraints for projecting future deglaciation is hindered by our incomplete understanding of evolving basal slip. Here, we develop a continuum model of water-saturated, cohesive till to quantify the interplay between meltwater percolation and till mobilization that governs changes in the depth of basal slip under fast-moving ice. Our model explains the puzzling variability of observed slip depths by relating localized till deformation to perturbations in pore-water pressure. It demonstrates that variable slip depth is an inherent property of the ice-meltwater-till system, which could help understand why some paleo-landforms like grounding-zone wedges appear to have formed quickly relative to current till-transport rates.
UR - http://www.scopus.com/inward/record.url?scp=85111481833&partnerID=8YFLogxK
U2 - 10.1038/s43247-020-00074-7
DO - 10.1038/s43247-020-00074-7
M3 - Article
SN - 2662-4435
VL - 1
SP - 1
EP - 8
JO - Communications Earth & Environment
JF - Communications Earth & Environment
IS - 1
M1 - 66
ER -