Late erosion pulse triggered by rapid melt in the cold‐based interior of the last Fennoscandian Ice Sheet, an example from Rogen
Abstract Ice sheet interiors are conventionally regarded as non‐erosive. Yet subglacial conditions may be transformed during deglaciation by the arrival of large volumes of meltwater at the ice sheet bed. The development of a dynamic meltwater drainage system and the onset of basal sliding have pote...
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Online Access: | http://dx.doi.org/10.1002/esp.5464 https://onlinelibrary.wiley.com/doi/pdf/10.1002/esp.5464 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/esp.5464 |
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crwiley:10.1002/esp.5464 2024-06-02T08:06:32+00:00 Late erosion pulse triggered by rapid melt in the cold‐based interior of the last Fennoscandian Ice Sheet, an example from Rogen van Boeckel, Mikis van Boeckel, Tayo Hall, Adrian M. 2022 http://dx.doi.org/10.1002/esp.5464 https://onlinelibrary.wiley.com/doi/pdf/10.1002/esp.5464 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/esp.5464 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Earth Surface Processes and Landforms volume 47, issue 14, page 3376-3394 ISSN 0197-9337 1096-9837 journal-article 2022 crwiley https://doi.org/10.1002/esp.5464 2024-05-03T11:38:52Z Abstract Ice sheet interiors are conventionally regarded as non‐erosive. Yet subglacial conditions may be transformed during deglaciation by the arrival of large volumes of meltwater at the ice sheet bed. The development of a dynamic meltwater drainage system and the onset of basal sliding have potential to increase erosion rates in bedrock and sediment. Here, we examine the impact of late deglacial thawing on the Rogen plateau, located near the former ice divide of the Fennoscandian Ice Sheet. We provide new maps of glacial and glacifluvial landforms which we combine with existing data on Quaternary sediments and landforms. Cross‐cutting and overlapping relations allow for an event sequence to be established of the deglaciation period. In the Early Holocene (< 11 ka), an ice lobe onset zone developed at the Rogen plateau. In places where meltwater reached the bed and where pressures rose to overpressure, it caused fracture dilation in horizontally bedded sandstones and rock brecciation. The onset of sliding and application of drag resulted in the mobilization of bedrock sheets. The establishment of meltwater corridors led to fluidization of sediments at the bed, dissection and modification of ribbed moraines and formation of murtoos and hummock corridors. During final stagnation of the ice sheet, meltwater drained through channels forming axial eskers. Bedrock erosion during deglaciation reached depths up to 4 m, and in conjunction with some recycling of till, generated 317 km 2 of boulder cover. The average erosion depths by removal and reworking of sediment are 0.9–1.1 m across areas below 900 m elevation. This study shows that when the cold‐based interiors of ice sheets become briefly activated by large subglacial meltwater delivery late in deglaciation, there can be significant reworking and erosion of rock and sediment. Article in Journal/Newspaper Fennoscandian Ice Sheet Wiley Online Library Rogen ENVELOPE(7.502,7.502,63.052,63.052) Earth Surface Processes and Landforms |
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Open Polar |
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Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
description |
Abstract Ice sheet interiors are conventionally regarded as non‐erosive. Yet subglacial conditions may be transformed during deglaciation by the arrival of large volumes of meltwater at the ice sheet bed. The development of a dynamic meltwater drainage system and the onset of basal sliding have potential to increase erosion rates in bedrock and sediment. Here, we examine the impact of late deglacial thawing on the Rogen plateau, located near the former ice divide of the Fennoscandian Ice Sheet. We provide new maps of glacial and glacifluvial landforms which we combine with existing data on Quaternary sediments and landforms. Cross‐cutting and overlapping relations allow for an event sequence to be established of the deglaciation period. In the Early Holocene (< 11 ka), an ice lobe onset zone developed at the Rogen plateau. In places where meltwater reached the bed and where pressures rose to overpressure, it caused fracture dilation in horizontally bedded sandstones and rock brecciation. The onset of sliding and application of drag resulted in the mobilization of bedrock sheets. The establishment of meltwater corridors led to fluidization of sediments at the bed, dissection and modification of ribbed moraines and formation of murtoos and hummock corridors. During final stagnation of the ice sheet, meltwater drained through channels forming axial eskers. Bedrock erosion during deglaciation reached depths up to 4 m, and in conjunction with some recycling of till, generated 317 km 2 of boulder cover. The average erosion depths by removal and reworking of sediment are 0.9–1.1 m across areas below 900 m elevation. This study shows that when the cold‐based interiors of ice sheets become briefly activated by large subglacial meltwater delivery late in deglaciation, there can be significant reworking and erosion of rock and sediment. |
format |
Article in Journal/Newspaper |
author |
van Boeckel, Mikis van Boeckel, Tayo Hall, Adrian M. |
spellingShingle |
van Boeckel, Mikis van Boeckel, Tayo Hall, Adrian M. Late erosion pulse triggered by rapid melt in the cold‐based interior of the last Fennoscandian Ice Sheet, an example from Rogen |
author_facet |
van Boeckel, Mikis van Boeckel, Tayo Hall, Adrian M. |
author_sort |
van Boeckel, Mikis |
title |
Late erosion pulse triggered by rapid melt in the cold‐based interior of the last Fennoscandian Ice Sheet, an example from Rogen |
title_short |
Late erosion pulse triggered by rapid melt in the cold‐based interior of the last Fennoscandian Ice Sheet, an example from Rogen |
title_full |
Late erosion pulse triggered by rapid melt in the cold‐based interior of the last Fennoscandian Ice Sheet, an example from Rogen |
title_fullStr |
Late erosion pulse triggered by rapid melt in the cold‐based interior of the last Fennoscandian Ice Sheet, an example from Rogen |
title_full_unstemmed |
Late erosion pulse triggered by rapid melt in the cold‐based interior of the last Fennoscandian Ice Sheet, an example from Rogen |
title_sort |
late erosion pulse triggered by rapid melt in the cold‐based interior of the last fennoscandian ice sheet, an example from rogen |
publisher |
Wiley |
publishDate |
2022 |
url |
http://dx.doi.org/10.1002/esp.5464 https://onlinelibrary.wiley.com/doi/pdf/10.1002/esp.5464 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/esp.5464 |
long_lat |
ENVELOPE(7.502,7.502,63.052,63.052) |
geographic |
Rogen |
geographic_facet |
Rogen |
genre |
Fennoscandian Ice Sheet |
genre_facet |
Fennoscandian Ice Sheet |
op_source |
Earth Surface Processes and Landforms volume 47, issue 14, page 3376-3394 ISSN 0197-9337 1096-9837 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/esp.5464 |
container_title |
Earth Surface Processes and Landforms |
_version_ |
1800751483498528768 |