Articles | Volume 14, issue 6
https://doi.org/10.5194/tc-14-1989-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-14-1989-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
18 Jun 2020
Research article |
| 18 Jun 2020
| 18 Jun 2020
A quasi-annual record of time-transgressive esker formation: implications for ice-sheet reconstruction and subglacial hydrology
Stephen J. Livingstone
CORRESPONDING AUTHOR
Department of Geography, University of Sheffield, Sheffield, UK
Emma L. M. Lewington
Department of Geography, University of Sheffield, Sheffield, UK
Chris D. Clark
Department of Geography, University of Sheffield, Sheffield, UK
Robert D. Storrar
Department of the Natural and Built Environment, Sheffield Hallam
University, Sheffield, UK
Andrew J. Sole
Department of Geography, University of Sheffield, Sheffield, UK
Isabelle McMartin
Geological Survey of Canada, Natural Resources Canada, Ottawa, ON, Canada
Nico Dewald
Department of Geography, University of Sheffield, Sheffield, UK
Department of Geography, University of Sheffield, Sheffield, UK
Related authors
Lauren D. Rawlins, David M. Rippin, Andrew J. Sole, Stephen J. Livingstone, and Kang Yang
The Cryosphere, 17, 4729–4750, https://doi.org/10.5194/tc-17-4729-2023, https://doi.org/10.5194/tc-17-4729-2023, 2023
Short summary
Short summary
We map and quantify surface rivers and lakes at Humboldt Glacier to examine seasonal evolution and provide new insights of network configuration and behaviour. A widespread supraglacial drainage network exists, expanding up the glacier as seasonal runoff increases. Large interannual variability affects the areal extent of this network, controlled by high- vs. low-melt years, with late summer network persistence likely preconditioning the surface for earlier drainage activity the following year.
Izabela Szuman, Jakub Z. Kalita, Christiaan R. Diemont, Stephen J. Livingstone, Chris D. Clark, and Martin Margold
The Cryosphere Discuss., https://doi.org/10.5194/tc-2023-107, https://doi.org/10.5194/tc-2023-107, 2023
Revised manuscript accepted for TC
Short summary
Short summary
The first Baltic wide glacial landform-based map is presented, filling in a geographical gap in the record that has been speculated about by palaeoglaciologists for over a century. Here we used newly available bathymetric data and provide landform evidence for corridors of fast ice flow that we interpret as ice streams. Where previous ice sheet-scale investigations inferred a single ice source, our mapping identifies flow and ice marginal geometries from both Swedish and north Bothnian sources.
Yubin Fan, Chang-Qing Ke, Xiaoyi Shen, Yao Xiao, Stephen J. Livingstone, and Andrew J. Sole
The Cryosphere, 17, 1775–1786, https://doi.org/10.5194/tc-17-1775-2023, https://doi.org/10.5194/tc-17-1775-2023, 2023
Short summary
Short summary
We used the new-generation ICESat-2 altimeter to detect and monitor active subglacial lakes in unprecedented spatiotemporal detail. We created a new inventory of 18 active subglacial lakes as well as their elevation and volume changes during 2019–2020, which provides an improved understanding of how the Greenland subglacial water system operates and how these lakes are fed by water from the ice surface.
Peter A. Tuckett, Jeremy C. Ely, Andrew J. Sole, James M. Lea, Stephen J. Livingstone, Julie M. Jones, and J. Melchior van Wessem
The Cryosphere, 15, 5785–5804, https://doi.org/10.5194/tc-15-5785-2021, https://doi.org/10.5194/tc-15-5785-2021, 2021
Short summary
Short summary
Lakes form on the surface of the Antarctic Ice Sheet during the summer. These lakes can generate further melt, break up floating ice shelves and alter ice dynamics. Here, we describe a new automated method for mapping surface lakes and apply our technique to the Amery Ice Shelf between 2005 and 2020. Lake area is highly variable between years, driven by large-scale climate patterns. This technique will help us understand the role of Antarctic surface lakes in our warming world.
Izabela Szuman, Jakub Z. Kalita, Marek W. Ewertowski, Chris D. Clark, Stephen J. Livingstone, and Leszek Kasprzak
Earth Syst. Sci. Data, 13, 4635–4651, https://doi.org/10.5194/essd-13-4635-2021, https://doi.org/10.5194/essd-13-4635-2021, 2021
Short summary
Short summary
The Baltic Ice Stream Complex was the most prominent ice stream of the last Scandinavian Ice Sheet, controlling ice sheet drainage and collapse. Our mapping effort, based on a lidar DEM, resulted in a dataset containing 5461 landforms over an area of 65 000 km2, which allows for reconstruction of the last Scandinavian Ice Sheet extent and dynamics from the Middle Weichselian ice sheet advance, 50–30 ka, through the Last Glacial Maximum, 25–21 ka, and Young Baltic advances, 18–15 ka.
Emma L. M. Lewington, Stephen J. Livingstone, Chris D. Clark, Andrew J. Sole, and Robert D. Storrar
The Cryosphere, 14, 2949–2976, https://doi.org/10.5194/tc-14-2949-2020, https://doi.org/10.5194/tc-14-2949-2020, 2020
Short summary
Short summary
We map visible traces of subglacial meltwater flow across Keewatin, Canada. Eskers are commonly observed to form within meltwater corridors up to a few kilometres wide, and we interpret different traces to have formed as part of the same integrated drainage system. In our proposed model, we suggest that eskers record the imprint of a central conduit while meltwater corridors represent the interaction with the surrounding distributed drainage system.
Stephen J. Livingstone, Andrew J. Sole, Robert D. Storrar, Devin Harrison, Neil Ross, and Jade Bowling
The Cryosphere, 13, 2789–2796, https://doi.org/10.5194/tc-13-2789-2019, https://doi.org/10.5194/tc-13-2789-2019, 2019
Short summary
Short summary
We report three new subglacial lakes close to the ice sheet margin of West Greenland. The lakes drained and refilled once each between 2009 and 2017, with two lakes draining in < 1 month during August 2014 and August 2015. The 2015 drainage caused a ~ 1-month down-glacier slowdown in ice flow and flooded the foreland, significantly modifying the braided river and depositing up to 8 m of sediment. These subglacial lakes offer accessible targets for future investigations and exploration.
Stephen J. Livingstone and Chris D. Clark
Earth Surf. Dynam., 4, 567–589, https://doi.org/10.5194/esurf-4-567-2016, https://doi.org/10.5194/esurf-4-567-2016, 2016
Short summary
Short summary
We mapped and analysed nearly 2000 large valleys that were formed by meltwater flowing under a former ice sheet. Our results demonstrate that valleys tend to cluster together in distinctive networks. The valleys themselves are typically < 20 km long, and 0.5–3 km wide, and their morphology is strongly influenced by local bed conditions (e.g. topography) and hydrology. We suggest valleys formed gradually, with secondary contributions from flood drainage of water stored on top of or under the ice.
S. J. Livingstone, C. D. Clark, J. Woodward, and J. Kingslake
The Cryosphere, 7, 1721–1740, https://doi.org/10.5194/tc-7-1721-2013, https://doi.org/10.5194/tc-7-1721-2013, 2013
Felix S. L. Ng
EGUsphere, https://doi.org/10.5194/egusphere-2024-1012, https://doi.org/10.5194/egusphere-2024-1012, 2024
Short summary
Short summary
Liquid veins and grain boundaries in ice can accelerate the decay of climate signals in δ18O and δD by short-circuiting the slow isotopic diffusion in crystal grains. This theory for ‘excess diffusion’ has not been confirmed experimentally. We show that if the mechanism occurs, then distinct isotopic patterns must form near grain junctions, offering a testable prediction of the theory. We calculate the patterns and describe an experimental scheme for testing ice-core samples for the mechanism.
Tancrède P. M. Leger, Christopher D. Clark, Carla Huynh, Sharman Jones, Jeremy C. Ely, Sarah L. Bradley, Christiaan Diemont, and Anna L. C. Hughes
Clim. Past, 20, 701–755, https://doi.org/10.5194/cp-20-701-2024, https://doi.org/10.5194/cp-20-701-2024, 2024
Short summary
Short summary
Projecting the future evolution of the Greenland Ice Sheet is key. However, it is still under the influence of past climate changes that occurred over thousands of years. This makes calibrating projection models against current knowledge of its past evolution (not yet achieved) important. To help with this, we produced a new Greenland-wide reconstruction of ice sheet extent by gathering all published studies dating its former retreat and by mapping its past margins at the ice sheet scale.
Benjamin J. Stoker, Helen E. Dulfer, Chris R. Stokes, Victoria H. Brown, Christopher D. Clark, Colm Ó Cofaigh, David J. A. Evans, Duane Froese, Sophie L. Norris, and Martin Margold
EGUsphere, https://doi.org/10.5194/egusphere-2024-137, https://doi.org/10.5194/egusphere-2024-137, 2024
Short summary
Short summary
The retreat of the northwestern Laurentide Ice Sheet allows us to investigate how the ice drainage network evolves over millennial timescales and understand the influence of climate forcing, glacial lakes, and the underlying geology on the rate of deglaciation. We reconstruct the changes in ice flow at 500-year intervals and identify rapid reorganisations of the drainage network, including variations in ice streaming that we link to climatically-driven changes in the ice sheet surface slope.
Lauren D. Rawlins, David M. Rippin, Andrew J. Sole, Stephen J. Livingstone, and Kang Yang
The Cryosphere, 17, 4729–4750, https://doi.org/10.5194/tc-17-4729-2023, https://doi.org/10.5194/tc-17-4729-2023, 2023
Short summary
Short summary
We map and quantify surface rivers and lakes at Humboldt Glacier to examine seasonal evolution and provide new insights of network configuration and behaviour. A widespread supraglacial drainage network exists, expanding up the glacier as seasonal runoff increases. Large interannual variability affects the areal extent of this network, controlled by high- vs. low-melt years, with late summer network persistence likely preconditioning the surface for earlier drainage activity the following year.
Felix S. L. Ng
The Cryosphere, 17, 3063–3082, https://doi.org/10.5194/tc-17-3063-2023, https://doi.org/10.5194/tc-17-3063-2023, 2023
Short summary
Short summary
The stable isotopes of oxygen and hydrogen in ice cores are routinely analysed for the climate signals which they carry. It has long been known that the system of water veins in ice facilitates isotopic diffusion. Here, mathematical modelling shows that water flow in the veins strongly accelerates the diffusion and the decay of climate signals. The process hampers methods using the variations in signal decay with depth to reconstruct past climatic temperature.
Izabela Szuman, Jakub Z. Kalita, Christiaan R. Diemont, Stephen J. Livingstone, Chris D. Clark, and Martin Margold
The Cryosphere Discuss., https://doi.org/10.5194/tc-2023-107, https://doi.org/10.5194/tc-2023-107, 2023
Revised manuscript accepted for TC
Short summary
Short summary
The first Baltic wide glacial landform-based map is presented, filling in a geographical gap in the record that has been speculated about by palaeoglaciologists for over a century. Here we used newly available bathymetric data and provide landform evidence for corridors of fast ice flow that we interpret as ice streams. Where previous ice sheet-scale investigations inferred a single ice source, our mapping identifies flow and ice marginal geometries from both Swedish and north Bothnian sources.
Yubin Fan, Chang-Qing Ke, Xiaoyi Shen, Yao Xiao, Stephen J. Livingstone, and Andrew J. Sole
The Cryosphere, 17, 1775–1786, https://doi.org/10.5194/tc-17-1775-2023, https://doi.org/10.5194/tc-17-1775-2023, 2023
Short summary
Short summary
We used the new-generation ICESat-2 altimeter to detect and monitor active subglacial lakes in unprecedented spatiotemporal detail. We created a new inventory of 18 active subglacial lakes as well as their elevation and volume changes during 2019–2020, which provides an improved understanding of how the Greenland subglacial water system operates and how these lakes are fed by water from the ice surface.
Sophie Goliber, Taryn Black, Ginny Catania, James M. Lea, Helene Olsen, Daniel Cheng, Suzanne Bevan, Anders Bjørk, Charlie Bunce, Stephen Brough, J. Rachel Carr, Tom Cowton, Alex Gardner, Dominik Fahrner, Emily Hill, Ian Joughin, Niels J. Korsgaard, Adrian Luckman, Twila Moon, Tavi Murray, Andrew Sole, Michael Wood, and Enze Zhang
The Cryosphere, 16, 3215–3233, https://doi.org/10.5194/tc-16-3215-2022, https://doi.org/10.5194/tc-16-3215-2022, 2022
Short summary
Short summary
Terminus traces have been used to understand how Greenland's glaciers have changed over time; however, manual digitization is time-intensive, and a lack of coordination leads to duplication of efforts. We have compiled a dataset of over 39 000 terminus traces for 278 glaciers for scientific and machine learning applications. We also provide an overview of an updated version of the Google Earth Engine Digitization Tool (GEEDiT), which has been developed specifically for the Greenland Ice Sheet.
Camilla M. Rootes and Christopher D. Clark
E&G Quaternary Sci. J., 71, 111–122, https://doi.org/10.5194/egqsj-71-111-2022, https://doi.org/10.5194/egqsj-71-111-2022, 2022
Short summary
Short summary
Glacial trimlines are visible breaks in vegetation or landforms that mark the former extent of glaciers. They are often observed as faint lines running across valley sides and are useful for mapping the three-dimensional shape of former glaciers or for assessing by how much present-day glaciers have thinned and retreated. Here we present the first application of a new trimline classification scheme to a case study location in central western Spitsbergen, Svalbard.
Benjamin Joseph Davison, Tom Cowton, Andrew Sole, Finlo Cottier, and Pete Nienow
The Cryosphere, 16, 1181–1196, https://doi.org/10.5194/tc-16-1181-2022, https://doi.org/10.5194/tc-16-1181-2022, 2022
Short summary
Short summary
The ocean is an important driver of Greenland glacier retreat. Icebergs influence ocean temperature in the vicinity of glaciers, which will affect glacier retreat rates, but the effect of icebergs on water temperature is poorly understood. In this study, we use a model to show that icebergs cause large changes to water properties next to Greenland's glaciers, which could influence ocean-driven glacier retreat around Greenland.
Peter A. Tuckett, Jeremy C. Ely, Andrew J. Sole, James M. Lea, Stephen J. Livingstone, Julie M. Jones, and J. Melchior van Wessem
The Cryosphere, 15, 5785–5804, https://doi.org/10.5194/tc-15-5785-2021, https://doi.org/10.5194/tc-15-5785-2021, 2021
Short summary
Short summary
Lakes form on the surface of the Antarctic Ice Sheet during the summer. These lakes can generate further melt, break up floating ice shelves and alter ice dynamics. Here, we describe a new automated method for mapping surface lakes and apply our technique to the Amery Ice Shelf between 2005 and 2020. Lake area is highly variable between years, driven by large-scale climate patterns. This technique will help us understand the role of Antarctic surface lakes in our warming world.
Izabela Szuman, Jakub Z. Kalita, Marek W. Ewertowski, Chris D. Clark, Stephen J. Livingstone, and Leszek Kasprzak
Earth Syst. Sci. Data, 13, 4635–4651, https://doi.org/10.5194/essd-13-4635-2021, https://doi.org/10.5194/essd-13-4635-2021, 2021
Short summary
Short summary
The Baltic Ice Stream Complex was the most prominent ice stream of the last Scandinavian Ice Sheet, controlling ice sheet drainage and collapse. Our mapping effort, based on a lidar DEM, resulted in a dataset containing 5461 landforms over an area of 65 000 km2, which allows for reconstruction of the last Scandinavian Ice Sheet extent and dynamics from the Middle Weichselian ice sheet advance, 50–30 ka, through the Last Glacial Maximum, 25–21 ka, and Young Baltic advances, 18–15 ka.
Jean Vérité, Édouard Ravier, Olivier Bourgeois, Stéphane Pochat, Thomas Lelandais, Régis Mourgues, Christopher D. Clark, Paul Bessin, David Peigné, and Nigel Atkinson
The Cryosphere, 15, 2889–2916, https://doi.org/10.5194/tc-15-2889-2021, https://doi.org/10.5194/tc-15-2889-2021, 2021
Short summary
Short summary
Subglacial bedforms are commonly used to reconstruct past glacial dynamics and investigate processes occuring at the ice–bed interface. Using analogue modelling and geomorphological mapping, we demonstrate that ridges with undulating crests, known as subglacial ribbed bedforms, are ubiquitous features along ice stream corridors. These bedforms provide a tantalizing glimpse into (1) the former positions of ice stream margins, (2) the ice lobe dynamics and (3) the meltwater drainage efficiency.
Felix S. L. Ng
The Cryosphere, 15, 1787–1810, https://doi.org/10.5194/tc-15-1787-2021, https://doi.org/10.5194/tc-15-1787-2021, 2021
Short summary
Short summary
Current theory predicts climate signals in the vein chemistry of ice cores to migrate, hampering their dating. I show that the Gibbs–Thomson effect, which has been overlooked, causes fast diffusion that prevents signals from surviving into deep ice. Hence the deep climatic peaks in Antarctic and Greenlandic ice must be due to impurities in the ice matrix (outside veins) and safe from migration. These findings reset our understanding of postdepositional changes of ice-core climate signals.
Emma L. M. Lewington, Stephen J. Livingstone, Chris D. Clark, Andrew J. Sole, and Robert D. Storrar
The Cryosphere, 14, 2949–2976, https://doi.org/10.5194/tc-14-2949-2020, https://doi.org/10.5194/tc-14-2949-2020, 2020
Short summary
Short summary
We map visible traces of subglacial meltwater flow across Keewatin, Canada. Eskers are commonly observed to form within meltwater corridors up to a few kilometres wide, and we interpret different traces to have formed as part of the same integrated drainage system. In our proposed model, we suggest that eskers record the imprint of a central conduit while meltwater corridors represent the interaction with the surrounding distributed drainage system.
Adam J. Hepburn, Tom Holt, Bryn Hubbard, and Felix Ng
Geosci. Instrum. Method. Data Syst., 8, 293–313, https://doi.org/10.5194/gi-8-293-2019, https://doi.org/10.5194/gi-8-293-2019, 2019
Short summary
Short summary
Currently, there exist thousands of unprocessed stereo pairs of satellite imagery which can be used to create models of the surface of Mars. This paper sets out a new open–source and free to use pipeline for creating these models. Our pipeline produces models of comparable quality to the limited number released to date but remains free to use and easily implemented by researchers, who may not necessarily have prior experience of DEM creation.
Stephen J. Livingstone, Andrew J. Sole, Robert D. Storrar, Devin Harrison, Neil Ross, and Jade Bowling
The Cryosphere, 13, 2789–2796, https://doi.org/10.5194/tc-13-2789-2019, https://doi.org/10.5194/tc-13-2789-2019, 2019
Short summary
Short summary
We report three new subglacial lakes close to the ice sheet margin of West Greenland. The lakes drained and refilled once each between 2009 and 2017, with two lakes draining in < 1 month during August 2014 and August 2015. The 2015 drainage caused a ~ 1-month down-glacier slowdown in ice flow and flooded the foreland, significantly modifying the braided river and depositing up to 8 m of sediment. These subglacial lakes offer accessible targets for future investigations and exploration.
Jeremy C. Ely, Chris D. Clark, David Small, and Richard C. A. Hindmarsh
Geosci. Model Dev., 12, 933–953, https://doi.org/10.5194/gmd-12-933-2019, https://doi.org/10.5194/gmd-12-933-2019, 2019
Short summary
Short summary
During the last 2.6 million years, the Earth's climate has cycled between cold glacials and warm interglacials, causing the growth and retreat of ice sheets. These ice sheets can be independently reconstructed using numerical models or from dated evidence that they leave behind (e.g. sediments, boulders). Here, we present a tool for comparing numerical model simulations with dated ice-sheet material. We demonstrate the utility of this tool by applying it to the last British–Irish ice sheet.
Niall Gandy, Lauren J. Gregoire, Jeremy C. Ely, Christopher D. Clark, David M. Hodgson, Victoria Lee, Tom Bradwell, and Ruza F. Ivanovic
The Cryosphere, 12, 3635–3651, https://doi.org/10.5194/tc-12-3635-2018, https://doi.org/10.5194/tc-12-3635-2018, 2018
Short summary
Short summary
We use the deglaciation of the last British–Irish Ice Sheet as a valuable case to examine the processes of contemporary ice sheet change, using an ice sheet model to simulate the Minch Ice Stream. We find that ice shelves were a control on retreat and that the Minch Ice Stream was vulnerable to the same marine mechanisms which threaten the future of the West Antarctic Ice Sheet. This demonstrates the importance of marine processes when projecting the future of our contemporary ice sheets.
Thomas Lelandais, Édouard Ravier, Stéphane Pochat, Olivier Bourgeois, Christopher Clark, Régis Mourgues, and Pierre Strzerzynski
The Cryosphere, 12, 2759–2772, https://doi.org/10.5194/tc-12-2759-2018, https://doi.org/10.5194/tc-12-2759-2018, 2018
Short summary
Short summary
Scattered observations suggest that subglacial meltwater routes drive ice stream dynamics and ice sheet stability. We use a new experimental approach to reconcile such observations into a coherent story connecting ice stream life cycles with subglacial hydrology and bed erosion. Results demonstrate that subglacial flooding, drainage reorganization, and valley development can control an ice stream lifespan, thus opening new perspectives on subglacial processes controlling ice sheet instabilities.
Christopher N. Williams, Stephen L. Cornford, Thomas M. Jordan, Julian A. Dowdeswell, Martin J. Siegert, Christopher D. Clark, Darrel A. Swift, Andrew Sole, Ian Fenty, and Jonathan L. Bamber
The Cryosphere, 11, 363–380, https://doi.org/10.5194/tc-11-363-2017, https://doi.org/10.5194/tc-11-363-2017, 2017
Short summary
Short summary
Knowledge of ice sheet bed topography and surrounding sea floor bathymetry is integral to the understanding of ice sheet processes. Existing elevation data products for Greenland underestimate fjord bathymetry due to sparse data availability. We present a new method to create physically based synthetic fjord bathymetry to fill these gaps, greatly improving on previously available datasets. This will assist in future elevation product development until further observations become available.
Stephen J. Livingstone and Chris D. Clark
Earth Surf. Dynam., 4, 567–589, https://doi.org/10.5194/esurf-4-567-2016, https://doi.org/10.5194/esurf-4-567-2016, 2016
Short summary
Short summary
We mapped and analysed nearly 2000 large valleys that were formed by meltwater flowing under a former ice sheet. Our results demonstrate that valleys tend to cluster together in distinctive networks. The valleys themselves are typically < 20 km long, and 0.5–3 km wide, and their morphology is strongly influenced by local bed conditions (e.g. topography) and hydrology. We suggest valleys formed gradually, with secondary contributions from flood drainage of water stored on top of or under the ice.
A. E. Jowett, E. Hanna, F. Ng, P. Huybrechts, and I. Janssens
The Cryosphere Discuss., https://doi.org/10.5194/tcd-9-5327-2015, https://doi.org/10.5194/tcd-9-5327-2015, 2015
Revised manuscript has not been submitted
S. de la Peña, I. M. Howat, P. W. Nienow, M. R. van den Broeke, E. Mosley-Thompson, S. F. Price, D. Mair, B. Noël, and A. J. Sole
The Cryosphere, 9, 1203–1211, https://doi.org/10.5194/tc-9-1203-2015, https://doi.org/10.5194/tc-9-1203-2015, 2015
Short summary
Short summary
This paper presents an assessment of changes in the near-surface structure of the accumulation zone of the Greenland Ice Sheet caused by an increase of melt at higher elevations in the last decade, especially during the unusually warm years of 2010 and 2012. The increase in melt and firn densification complicate the interpretation of changes in the ice volume, and the observed increase in firn ice content may reduce the important meltwater buffering capacity of the Greenland Ice Sheet.
C. C. Clason, D. W. F. Mair, P. W. Nienow, I. D. Bartholomew, A. Sole, S. Palmer, and W. Schwanghart
The Cryosphere, 9, 123–138, https://doi.org/10.5194/tc-9-123-2015, https://doi.org/10.5194/tc-9-123-2015, 2015
N. Chauché, A. Hubbard, J.-C. Gascard, J. E. Box, R. Bates, M. Koppes, A. Sole, P. Christoffersen, and H. Patton
The Cryosphere, 8, 1457–1468, https://doi.org/10.5194/tc-8-1457-2014, https://doi.org/10.5194/tc-8-1457-2014, 2014
H. Patton, A. Hubbard, T. Bradwell, N. F. Glasser, M. J. Hambrey, and C. D. Clark
Earth Surf. Dynam., 1, 53–65, https://doi.org/10.5194/esurf-1-53-2013, https://doi.org/10.5194/esurf-1-53-2013, 2013
S. J. Livingstone, C. D. Clark, J. Woodward, and J. Kingslake
The Cryosphere, 7, 1721–1740, https://doi.org/10.5194/tc-7-1721-2013, https://doi.org/10.5194/tc-7-1721-2013, 2013
Related subject area
Discipline: Ice sheets | Subject: Geomorphology
Dynamical response of the southwestern Laurentide Ice Sheet to rapid Bølling–Allerød warming
Effects of topographic and meteorological parameters on the surface area loss of ice aprons in the Mont Blanc massif (European Alps)
Geomorphology and shallow sub-sea-floor structures underneath the Ekström Ice Shelf, Antarctica
Formation of ribbed bedforms below shear margins and lobes of palaeo-ice streams
Ice-stream flow switching by up-ice propagation of instabilities along glacial marginal troughs
Basal control of supraglacial meltwater catchments on the Greenland Ice Sheet
How dynamic are ice-stream beds?
Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels
Sophie L. Norris, Martin Margold, David J. A. Evans, Nigel Atkinson, and Duane G. Froese
The Cryosphere, 18, 1533–1559, https://doi.org/10.5194/tc-18-1533-2024, https://doi.org/10.5194/tc-18-1533-2024, 2024
Short summary
Short summary
Associated with climate change between the Last Glacial Maximum and the current interglacial period, we reconstruct the behaviour of the southwestern Laurentide Ice Sheet, which covered the Canadian Prairies, using detailed landform mapping. Our reconstruction depicts three shifts in the ice sheet’s dynamics. We suggest these changes resulted from ice sheet thinning triggered by abrupt climatic change. However, we show that regional lithology and topography also play an important role.
Suvrat Kaushik, Ludovic Ravanel, Florence Magnin, Yajing Yan, Emmanuel Trouve, and Diego Cusicanqui
The Cryosphere, 16, 4251–4271, https://doi.org/10.5194/tc-16-4251-2022, https://doi.org/10.5194/tc-16-4251-2022, 2022
Short summary
Short summary
Climate change impacts all parts of the cryosphere but most importantly the smaller ice bodies like ice aprons (IAs). This study is the first attempt on a regional scale to assess the impacts of the changing climate on these small but very important ice bodies. Our study shows that IAs have consistently lost mass over the past decades. The effects of climate variables, particularly temperature and precipitation and topographic factors, were analysed on the loss of IA area.
Astrid Oetting, Emma C. Smith, Jan Erik Arndt, Boris Dorschel, Reinhard Drews, Todd A. Ehlers, Christoph Gaedicke, Coen Hofstede, Johann P. Klages, Gerhard Kuhn, Astrid Lambrecht, Andreas Läufer, Christoph Mayer, Ralf Tiedemann, Frank Wilhelms, and Olaf Eisen
The Cryosphere, 16, 2051–2066, https://doi.org/10.5194/tc-16-2051-2022, https://doi.org/10.5194/tc-16-2051-2022, 2022
Short summary
Short summary
This study combines a variety of geophysical measurements in front of and beneath the Ekström Ice Shelf in order to identify and interpret geomorphological evidences of past ice sheet flow, extent and retreat.
The maximal extent of grounded ice in this region was 11 km away from the continental shelf break.
The thickness of palaeo-ice on the calving front around the LGM was estimated to be at least 305 to 320 m.
We provide essential boundary conditions for palaeo-ice-sheet models.
Jean Vérité, Édouard Ravier, Olivier Bourgeois, Stéphane Pochat, Thomas Lelandais, Régis Mourgues, Christopher D. Clark, Paul Bessin, David Peigné, and Nigel Atkinson
The Cryosphere, 15, 2889–2916, https://doi.org/10.5194/tc-15-2889-2021, https://doi.org/10.5194/tc-15-2889-2021, 2021
Short summary
Short summary
Subglacial bedforms are commonly used to reconstruct past glacial dynamics and investigate processes occuring at the ice–bed interface. Using analogue modelling and geomorphological mapping, we demonstrate that ridges with undulating crests, known as subglacial ribbed bedforms, are ubiquitous features along ice stream corridors. These bedforms provide a tantalizing glimpse into (1) the former positions of ice stream margins, (2) the ice lobe dynamics and (3) the meltwater drainage efficiency.
Etienne Brouard and Patrick Lajeunesse
The Cryosphere, 13, 981–996, https://doi.org/10.5194/tc-13-981-2019, https://doi.org/10.5194/tc-13-981-2019, 2019
Short summary
Short summary
Modifications in ice-stream networks have major impacts on ice sheet mass balance and global sea level. However, the mechanisms controlling ice-stream switching remain poorly understood. We report a flow switch in an ice-stream system that occurred on the Baffin Island shelf through the erosion of a marginal trough. Up-ice propagation of ice streams through marginal troughs can lead to the piracy of neighboring ice catchments, which induces an adjacent ice-stream switch and shutdown.
Josh Crozier, Leif Karlstrom, and Kang Yang
The Cryosphere, 12, 3383–3407, https://doi.org/10.5194/tc-12-3383-2018, https://doi.org/10.5194/tc-12-3383-2018, 2018
Short summary
Short summary
Understanding ice sheet surface meltwater routing is important for modeling and predicting ice sheet evolution. We determined that bed topography underlying the Greenland Ice Sheet is the primary influence on 1–10 km scale ice surface topography, and on drainage-basin-scale surface meltwater routing. We provide a simple means of predicting the response of surface meltwater routing to changing ice flow conditions and explore the implications of this for subglacial hydrology.
Damon Davies, Robert G. Bingham, Edward C. King, Andrew M. Smith, Alex M. Brisbourne, Matteo Spagnolo, Alastair G. C. Graham, Anna E. Hogg, and David G. Vaughan
The Cryosphere, 12, 1615–1628, https://doi.org/10.5194/tc-12-1615-2018, https://doi.org/10.5194/tc-12-1615-2018, 2018
Short summary
Short summary
This paper investigates the dynamics of ice stream beds using repeat geophysical surveys of the bed of Pine Island Glacier, West Antarctica; 60 km of the bed was surveyed, comprising the most extensive repeat ground-based geophysical surveys of an Antarctic ice stream; 90 % of the surveyed bed shows no significant change despite the glacier increasing in speed by up to 40 % over the last decade. This result suggests that ice stream beds are potentially more stable than previously suggested.
Anna Grau Galofre, A. Mark Jellinek, Gordon R. Osinski, Michael Zanetti, and Antero Kukko
The Cryosphere, 12, 1461–1478, https://doi.org/10.5194/tc-12-1461-2018, https://doi.org/10.5194/tc-12-1461-2018, 2018
Short summary
Short summary
Water accumulated at the base of ice sheets is the main driver of glacier acceleration and loss of ice mass in Arctic regions. Previously glaciated landscapes sculpted by this water carry information about how ice sheets collapse and ultimately disappear. The search for these landscapes took us to the high Arctic, to explore channels that formed under kilometers of ice during the last ice age. In this work we describe how subglacial channels look and how they helped to drain an ice sheet.
Cited articles
Ahokangas, E. and Mäkinen, J.: Sedimentology of an ice lobe margin esker
with implications for the deglacial dynamics of the Finnish Lake District
lobe trunk, Boreas, 43, 90–106, https://doi.org/10.1111/bor.12023, 2014.
Aylsworth, J. M. and Shilts, W. W.: Glacial features around the Keewatin Ice
Divide: Districts of Mackenzie and Keewatin, Geol. Surv. Canada,
Ottawa, Paper 88-24, 21 pp., 1989.
Banerjee, I. and McDonald, B. C.: Nature of esker sedimentation, in: Glaciofluvial and Ghciolacustrine
Sedimentation, edited by: Jopling,
A. V. and McDonald, B. C., SEPM Special Publication 23, 132–154, 1975.
Beaud, F., Flowers, G. E., and Venditti, J. G.: Modeling Sediment Transport
in Ice-Walled Subglacial Channels and Its Implications for Esker Formation
and Proglacial Sediment Yields, J. Geophys. Res.-Earth
Surf., 123, 3206–3227, https://doi.org/10.1029/2018jf004779, 2018.
Benn, D. I., Warren, C. R., and Mottram, R. H.: Calving processes and the
dynamics of calving glaciers, Earth-Sci. Rev., 82, 143–179,
https://doi.org/10.1016/j.earscirev.2007.02.002, 2007.
Boulton, G. S. and Clark, C. D.: A highly mobile Laurentide ice sheet
revealed by satellite images of glacial lineations, Nature, 346, 813–817,
https://doi.org/10.1038/346813a0, 1990a.
Boulton, G. S. and Clark, C. D.: The Laurentide ice sheet through the last
glacial cycle: the topology of drift lineations as a key to the dynamic
behaviour of former ice sheets, Earth Env. Sci. T. R. So., 81, 327–347,
https://doi.org/10.1017/s0263593300020836, 1990b.
Boulton, G. S., Dongelmans, M., Punkari, and Broadgate, M.: Paleoglaciology of an ice sheet through a glacial cycle: the European ice sheet through the Weichselian, Quater. Sci. Rev., 20, 591–625, https://doi.org/10.1016/S0277-3791(00)00160-8, 2001.
Bouvier, V., Johnson, M. D., and Påsse, T.: Distribution, genesis and
annual-origin of De Geer moraines in Sweden: insights revealed by LiDAR,
GFF, 137, 319–333, https://doi.org/10.1080/11035897.2015.1089933, 2015.
Brennand, T. A.: Macroforms, large bedforms and rhythmic sedimentary
sequences in subglacial eskers, south-central Ontario: implications for
esker genesis and meltwater regime, Sedimentary Geol., 91, 9–55,
https://doi.org/10.1016/0037-0738(94)90122-8, 1994.
Brennand, T. A.: Deglacial meltwater drainage and glaciodynamics: inferences
from Laurentide eskers, Canada, Geomorphology, 32, 263–293,
https://doi.org/10.1016/s0169-555x(99)00100-2, 2000.
Chandler, B. M., Lovell, H., Boston, C. M., Lukas, S., Barr, I. D.,
Benediktsson, Í. Ö., Benn, D. I., Clark, C. D., Darvill, C. M.,
Evans, D. J., and Ewertowski, M. W.: Glacial geomorphological mapping: A
review of approaches and frameworks for best practice, Earth-Sci.
Rev., 185, 806–846, https://doi.org/10.1016/j.earscirev.2018.07.015,
2018.
Cheel, R. J. and Rust, B. R.: A sequence of soft-sediment deformation
(dewatering) structures in Late Quaternary subaqueous outwash near Ottawa,
Canada, Sediment. Geol., 47, 77–93,
https://doi.org/10.1016/0037-0738(86)90072-2, 1986.
Dalton, A. S., Margold, M., Stokes, C. R., et al.: An updated radiocarbon-based ice margin chronology
for the last deglaciation of the North American Ice Sheet Complex,
Quaternary Sci. Rev., 234, 106223, https://doi.org/10.1016/j.quascirev.2020.106223, 2020.
De Geer, G.: Om rullstensåsarnas bildningssätt, Geologiska
Föreningen i Stockholm Förhandlingar, 19, 366–388, https://doi.org/10.1080/11035899709448614, 1897.
De Geer, G.: Geochronolgie der letzten 12 000 Jahre, The 11th International
Geological Congress in Stockholm, 457–471, 1910.
De Geer, G.: Geochronologia Suecica Principles, Kungliga Svenska
Vetenskapsakademiens Handlingar III, 18, 367 pp., 1940.
Dowling, T. P., Möller, P., and Spagnolo, M.: Rapid subglacial
streamlined bedform formation at a calving bay margin, J. Quatern.
Sci., 31, 879–892, https://doi.org/10.1002/jqs.2912, 2016.
Dyke, A. S.: An outline of North American deglaciation with emphasis on
central and northern Canada, in: Quaternary Glaciations: Extent and
Chronology, Part II, edited by: Ehlers, J. and Gibbard, P. L., Elsevier, Amsterdam, 373–424, 2004.
Dyke, A. S., Moore, A., and Robertson, L.: Deglaciation of North America,
Geol. Surv. Canada, Open File 1574, Natural Resources Canada,
Ottawa, https://doi.org/10.4095/214399, 2003.
Flink, A. E., Noormets, R., Kirchner, N., Benn, D. I., Luckman, A., and
Lovell, H.: The evolution of a submarine landform record following recent
and multiple surges of Tunabreen glacier, Svalbard, Quatern. Sci.
Rev., 108, 37–50, https://doi.org/10.1016/j.quascirev.2014.11.006, 2015.
Fulton, R. J.: Surficial materials of Canada, Geol. Surv. Canada,
“A” Series Map 1880A, 1 sheet, https://doi.org/10.4095/205040,
1995.
Gorrell, G. and Shaw, J.: Deposition in an esker, bead and fan complex,
Lanark, Ontario, Canada, Sediment. Geol., 72, 285–314,
https://doi.org/10.1016/0037-0738(91)90016-7, 1991.
Greenwood, S. L., Clason, C. C., Helanow, C., and Margold, M.: Theoretical,
contemporary observational and palaeo-perspectives on ice sheet hydrology:
processes and products, Earth-Sci. Rev., 155, 1–27,
https://doi.org/10.1016/j.earscirev.2016.01.010, 2016.
Hebrand, M. and Åmark, M.: Esker formation and glacier dynamics in
eastern Skane and adjacent areas, southern Sweden, Boreas, 18, 67–81,
https://doi.org/10.1111/j.1502-3885.1989.tb00372.x, 1989.
Hewitt, I. J.: Modelling distributed and channelized subglacial drainage: the https://doi.org/10.3189/002214311796405951, 2011.
Hewitt, I. J. and Creyts, T. T.: A model for the formation of eskers,
Geophys. Res. Lett., 46, 6673–6680, https://doi.org/10.1029/2019gl082304, 2019.
Hoppe, G.: Problems of glacial morphology and the Ice Age, Geogr.
Annaler, 39, 1–18, https://doi.org/10.2307/520339, 1957.
Howat, I. M. and Eddy, A.: Multi-decadal retreat of Greenland's
marine-terminating glaciers, J. Glaciol., 57, 389–396,
https://doi.org/10.3189/002214311796905631, 2011.
Klassen, R. A.: Drift composition and glacial dispersal trains, Baker Lake
area, District of Keewatin, Northwest Territories, Geol. Surv.
Canada, https://doi.org/10.4095/204885, 1995.
Lewington, E. L., Livingstone, S. J., Sole, A. J., Clark, C. D., and Ng, F.
S.: An automated method for mapping geomorphological expressions of former
subglacial meltwater pathways (hummock corridors) from high resolution
digital elevation data, Geomorphology, 339, 70–86,
https://doi.org/10.1016/j.geomorph.2019.04.013, 2019.
Lindén, M. and Möller, P.: Marginal formation of De Geer moraines
and their implications to the dynamics of grounding-line recession, J. Quatern. Sci., 20, 113–133, https://doi.org/10.1002/jqs.902,
2005.
Livingstone, S. J., Cofaigh, C. Ó., Stokes, C. R., Hillenbrand, C. D.,
Vieli, A., and Jamieson, S. S.: Antarctic palaeo-ice streams, Earth-Sci.
Rev., 111, 90–128, https://doi.org/10.1016/j.earscirev.2011.10.003,
2012.
Livingstone, S. J., Lewington, E. L., Clark, C. D., Storrar, R. D., Sole, A. J., McMartin, I., Dewald, N., and Ng, F.: Mapping of meltwater features and De Geer moraines in central Nunavut, Canada from the high-resolution (2 m) ArcticDEM, https://doi.org/10.15131/shef.data.12315221, 2020.
Lundqvist, J.: Studies of the Quaternary History and Deposits of
Värmland, Sweden – Experiences Made While Preparing a Survey Map,
Avhandlingar och Uppsatser ser. C 559, Sveriges Geologiska Undersökning,
Stockholm, 1958.
Mäkinen, J.: Time-transgressive deposits of repeated depositional
sequences within interlobate glaciofluvial (esker) sediments in
Köyliö, SW Finland, Sedimentology, 50, 327–360,
https://doi.org/10.1046/j.1365-3091.2003.00557.x, 2003.
McMartin, I.: Till composition across the Meliadine Trend, Rankin Inlet
area, Kivalliq region, Nunavut. Geol. Surv. Canada, Open File 3747,
https://doi.org/10.4095/211793, 2000.
McMartin, I. and Henderson, P.: Evidence from Keewatin (central Nunavut) for
paleo-ice divide migration, Geogr. Phys. Quatern., 58,
163–186, https://doi.org/10.7202/013137ar, 2004.
McMartin, I., Day, S. J. A., Randour, I., Roy, M., Byatt, J., LaRocque, A.,
and Leblon, B.: Report of 2016 activities for the surficial mapping and
sampling surveys in the Tehery-Wager GEM-2 Rae Project area, Geol. Surv. Canada, Open File 8134, https://doi.org/10.4095/299385, 2016.
McMartin, I., Randour, I., and Wodicka, N.: Till composition across the
Keewatin Ice Divide in the Tehery-Wager GEM-2 Rae project area, Nunavut,
Geol. Surv. Canada, Open File 8563, https://doi.org/10.4095/314707,
2019.
Möller, H.: Annuella och interannuella ändmoräner (Annual and
interannual end moraines), GFF, 84, 134–143,
https://doi.org/10.1080/11035896209449211, 1962.
Murray, T., Scharrer, K., Selmes, N., Booth, A. D., James, T. D., Bevan, S.
L., Bradley, J., Cook, S., Llana, L. C., Drocourt, Y., and Dyke, L.:
Extensive retreat of Greenland tidewater glaciers, 2000–2010, Arct.
Antarct. Alp. Res., 47, 427–447,
https://doi.org/10.1657/aaar0014-049, 2015.
Noh, M. J. and Howat, I. M.: Automated stereo-photogrammetric DEM generation
at high latitudes: Surface Extraction with TIN-based Search-space
Minimization (SETSM) validation and demonstration over glaciated regions,
GISci. Remote Sens., 52, 198–217,
https://doi.org/10.1080/15481603.2015.1008621, 2015.
Ojala, A. E.: Appearance of De Geer moraines in southern and western
Finland – Implications for reconstructing glacier retreat dynamics,
Geomorph., 255, 16–25, https://doi.org/10.1016/j.geomorph.2015.12.005,
2016.
Ojala, A. E., Putkinen, N., Palmu, J. P., and Nenonen, K.: Characterization
of De Geer moraines in Finland based on LiDAR DEM mapping, GFF, 137,
304–318, https://doi.org/10.1080/11035897.2015.1050449, 2015.
Ottesen, D. and Dowdeswell, J. A.: Assemblages of submarine landforms
produced by tidewater glaciers in Svalbard, J. Geophys. Res.-Earth Surf., 111, F01016, https://doi.org/10.1029/2005jf000330, 2006.
Paul, D., Hanmer, S., Tella, S., Peterson, T. D., and LeCheminant, A. N.:
Compilation, bedrock geology of part of the western Churchill Province,
Nunavut-Northwest Territories. Geol. Surv. Canada, Ottawa, Open
File 4236, Scale 1 : 1 000 000, https://doi.org/10.4095/213530, 2002.
Porter, C., Morin, P., Howat, I., Noh, M.-J., Bates, B., Peterman, K., Keesey, S., Schlenk, M., Gardiner, J., Tomko, K., Willis, M., Kelleher, C., Cloutier, M., Husby, E., Foga, S., Nakamura, H., Platson, M., Wethington Jr., M., Williamson, C., Bauer, G., Enos, J., Arnold, G., Kramer, W., Becker, P., Doshi, A., D'Souza, C., Cummens, P., Laurier, F., and Bojesen, M.: ArcticDEM, V1, Harvard Dataverse, https://doi.org/10.7910/DVN/OHHUKH, 2018.
Powell, R. D. and Molnia, B. F.: Glacimarine sedimentary processes, facies
and morphology of the south-southeast Alaska shelf and fjords, Mar.
Geol., 85, 359–390, https://doi.org/10.1016/0025-3227(89)90160-6,
1989.
Powell, R. D.: Glacimarine processes at grounding-line fans and their growth
to ice-contact deltas, Geological Society, London, Special Publications,
53, 53–73, https://doi.org/10.1144/gsl.sp.1990.053.01.03, 1990.
Prest, V. K., Grant, D. R., and Rampton, V. N.: Glacial map of Canada,
Geol. Surv. Canada, Department of Energy, Mines and Resources,
1968.
Randour, I., McMartin, I., and Roy, M.: Study of the postglacial marine limit
between Wager Bay and Chesterfield Inlet, western Hudson Bay, Nunavut,
Canada-Nunavut Geoscience Office, Summary of Activities 2016, 51–60, 2016.
Rust, B. R. and Romanelli, R.: Late Quaternary subaqueous outwash deposits
near Ottawa, Canada, Glaciofluvial and Glaciolacustrine Sedimentation,
177–192, https://doi.org/10.2110/pec.75.23.0177, 1975.
Schild, K. M. and Hamilton, G. S.: Seasonal variations of outlet glacier
terminus position in Greenland, J. Glaciol., 59, 759–770,
https://doi.org/10.3189/2013jog12j238, 2013.
Shilts, W. W.: Glaciation of the Hudson Bay region, in: Canadian Inland Seas, Martini, I. P.,
Elsevier, Amsterdam, 55–78,
https://doi.org/10.1016/s0422-9894(08)70897-3, 1986.
Shilts, W. W., Cunningham, C. M., and Kaszycki, C. A.: Keewatin Ice
Sheet – Re-evaluation of the traditional concept of the Laurentide Ice
Sheet, Geology, 7, 537–541,
https://doi.org/10.1130/0091-7613(1979)7<537:kisott>2.0.co;2, 1979.
Simon, K. M, Thomas, S. J, Forbes, D. L., Telka, A. M., Dyke, A. S., and
Henton, J. A.: A relative sea-level history for Arviat, Nunavut, and
implications for Laurentide Ice Sheet thickness west of Hudson Bay,
Quatern. Res., 82, 185–197,
https://doi.org/10.1016/j.yqres.2014.04.002, 2014.
Storrar, R. D., Stokes, C. R., and Evans, D. J. A.: A map of large Canadian
eskers from Landsat satellite imagery, J. Maps, 9, 456–473,
https://doi.org/10.1080/17445647.2013.815591, 2013.
Storrar, R. D., Stokes, C. R., and Evans, D. J. A.: Morphometry and pattern of
a large sample (> 20,000) of Canadian eskers and implications for
subglacial drainage beneath ice sheets, Quatern. Sci. Rev., 105,
1–25, https://doi.org/10.1016/j.quascirev.2014.09.013, 2014.
Stroeven, A. P., Hättestrand, C., Kleman, J., Heyman, J., Fabel, D.,
Fredin, O., Goodfellow, B. W., Harbor, J. M., Jansen, J. D., Olsen, L.,
Caffee, M. W., Fink, D., Lundqvist, J., Rosqvist, G. C., Strömberg, B.,
and Jansson, K. N.: Deglaciation of Fennoscandia, Quatern. Sci.
Rev., 147, 91–121, https://doi.org/10.1016/j.quascirev.2015.09.016, 2016.
Strömberg, B.: Mapping and geochronological investigation in some moraine
areas of south-central Sweden, Geogr. Ann. Ser. A, 47, 73–82,
https://doi.org/10.1080/04353676.1965.11879715, 1965.
Strömberg, B.: Calving bays, striae and moraines at Gysinge-Hedesunda,
central Sweden, Geogr. Annaler. A, 63,
149–154, https://doi.org/10.1080/04353676.1981.11880028, 1981.
Todd, B. J., Valentine, P. C., Longva, O., and Shaw, J.: Glacial landforms on
German Bank, Scotian Shelf: evidence for Late Wisconsinan ice-sheet dynamics
and implications for the formation of De Geer moraines, Boreas, 36,
148–169, https://doi.org/10.1111/j.1502-3885.2007.tb01189.x, 2007.
Tyrrell, J. B.: The glaciation of north central Canada, J.
Geol., 6, 147–160, https://doi.org/10.1086/608030, 1898.
Warren, W. P. and Ashley, G. M.: Origins of the ice-contact stratified
ridges (eskers) of Ireland, J. Sediment. Res., 64,
433–449, https://doi.org/10.1306/d4267dd9-2b26-11d7-8648000102c1865d, 1994.
Winsborrow, M. C., Andreassen, K., Corner, G. D., and Laberg, J. S.:
Deglaciation of a marine-based ice sheet: Late Weichselian palaeo-ice
dynamics and retreat in the southern Barents Sea reconstructed from onshore
and offshore glacial geomorphology, Quatern. Sci. Rev., 29,
424–442, https://doi.org/10.1016/j.quascirev.2009.10.001, 2010.
Zilliacus, H.: Genesis of De Geer moraines in Finland, Sediment. Geol.,
62, 309–317, https://doi.org/10.1016/0037-0738(89)90121-8,
1989.
Short summary
We map series of aligned mounds (esker beads) across central Nunavut, Canada. Mounds are interpreted to have formed roughly annually as sediment carried by subglacial rivers is deposited at the ice margin. Chains of mounds are formed as the ice retreats. This high-resolution (annual) record allows us to constrain the pace of ice retreat, sediment fluxes, and the style of drainage through time. In particular, we suggest that eskers in general record a composite signature of ice-marginal drainage.
We map series of aligned mounds (esker beads) across central Nunavut, Canada. Mounds are...
