Erosional and Depositional Features of Glacial Meltwater Discharges on the Eastern Canadian Continental Margin
Large-scale glacial meltwater discharges have long been recognized as important sedimentological agents on the eastern Canadian continental margin. Previous studies in Eastern Valley of Laurentian Fan and Orphan Basin have elucidated aspects of processes and timing of glacial discharges, principally...
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ftuninhampshire:oai:scholars.unh.edu:ccom-2318 2023-05-15T16:35:39+02:00 Erosional and Depositional Features of Glacial Meltwater Discharges on the Eastern Canadian Continental Margin Piper, Davide J.W. Deptuck, M. E. Mosher, David C. Hughes Clarke, John E. Migeon, Sebastien 2012-01-01T08:00:00Z https://scholars.unh.edu/ccom/1319 https://pubs.geoscienceworld.org/books/book/1195/chapter/11544076/erosional-and-depositional-features-of-glacial unknown University of New Hampshire Scholars' Repository https://scholars.unh.edu/ccom/1319 https://pubs.geoscienceworld.org/books/book/1195/chapter/11544076/erosional-and-depositional-features-of-glacial Center for Coastal and Ocean Mapping text 2012 ftuninhampshire 2023-01-30T21:47:55Z Large-scale glacial meltwater discharges have long been recognized as important sedimentological agents on the eastern Canadian continental margin. Previous studies in Eastern Valley of Laurentian Fan and Orphan Basin have elucidated aspects of processes and timing of glacial discharges, principally from seismic-reflection profiles and deep-water sidescan sonar. New multibeam bathymetry and piston cores show evidence of important meltwater processes seaward of all transverse troughs on the continental shelf, from Hudson Strait to the Scotian margin. Meltwater cuts broad flat-floored valleys and sculpts residual buttes, depositing thick-bedded gravel and sand turbidites, and builds submarine fans. Based on morphology, a wide range of scales of meltwater discharge may take place. Meltwater is intimately linked with supply of fluid glacial diamict (till) that on gentler slopes (< 2.5°) creates glacigenic debris flows but on steeper slopes breaks up, entrains water, and transforms to create erosive turbidity currents. Three end-member processes are recognized on submarine fans seaward of transverse troughs that were occupied by ice streams: glacigenic debris flows, turbidity-current deposition of channel–levee complexes, and blocky mass-transport deposits resulting from debris avalanches. The relative importance of meltwater appears greater at lower than at higher latitudes, whereas the formation of glacigenic debris flows is dependent on gradient. Pleistocene processes have resulted in slopes that are graded, implying that most sand deposition was on the continental rise. Text Hudson Strait University of New Hampshire: Scholars Repository Hudson Hudson Strait ENVELOPE(-70.000,-70.000,62.000,62.000) |
institution |
Open Polar |
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University of New Hampshire: Scholars Repository |
op_collection_id |
ftuninhampshire |
language |
unknown |
description |
Large-scale glacial meltwater discharges have long been recognized as important sedimentological agents on the eastern Canadian continental margin. Previous studies in Eastern Valley of Laurentian Fan and Orphan Basin have elucidated aspects of processes and timing of glacial discharges, principally from seismic-reflection profiles and deep-water sidescan sonar. New multibeam bathymetry and piston cores show evidence of important meltwater processes seaward of all transverse troughs on the continental shelf, from Hudson Strait to the Scotian margin. Meltwater cuts broad flat-floored valleys and sculpts residual buttes, depositing thick-bedded gravel and sand turbidites, and builds submarine fans. Based on morphology, a wide range of scales of meltwater discharge may take place. Meltwater is intimately linked with supply of fluid glacial diamict (till) that on gentler slopes (< 2.5°) creates glacigenic debris flows but on steeper slopes breaks up, entrains water, and transforms to create erosive turbidity currents. Three end-member processes are recognized on submarine fans seaward of transverse troughs that were occupied by ice streams: glacigenic debris flows, turbidity-current deposition of channel–levee complexes, and blocky mass-transport deposits resulting from debris avalanches. The relative importance of meltwater appears greater at lower than at higher latitudes, whereas the formation of glacigenic debris flows is dependent on gradient. Pleistocene processes have resulted in slopes that are graded, implying that most sand deposition was on the continental rise. |
format |
Text |
author |
Piper, Davide J.W. Deptuck, M. E. Mosher, David C. Hughes Clarke, John E. Migeon, Sebastien |
spellingShingle |
Piper, Davide J.W. Deptuck, M. E. Mosher, David C. Hughes Clarke, John E. Migeon, Sebastien Erosional and Depositional Features of Glacial Meltwater Discharges on the Eastern Canadian Continental Margin |
author_facet |
Piper, Davide J.W. Deptuck, M. E. Mosher, David C. Hughes Clarke, John E. Migeon, Sebastien |
author_sort |
Piper, Davide J.W. |
title |
Erosional and Depositional Features of Glacial Meltwater Discharges on the Eastern Canadian Continental Margin |
title_short |
Erosional and Depositional Features of Glacial Meltwater Discharges on the Eastern Canadian Continental Margin |
title_full |
Erosional and Depositional Features of Glacial Meltwater Discharges on the Eastern Canadian Continental Margin |
title_fullStr |
Erosional and Depositional Features of Glacial Meltwater Discharges on the Eastern Canadian Continental Margin |
title_full_unstemmed |
Erosional and Depositional Features of Glacial Meltwater Discharges on the Eastern Canadian Continental Margin |
title_sort |
erosional and depositional features of glacial meltwater discharges on the eastern canadian continental margin |
publisher |
University of New Hampshire Scholars' Repository |
publishDate |
2012 |
url |
https://scholars.unh.edu/ccom/1319 https://pubs.geoscienceworld.org/books/book/1195/chapter/11544076/erosional-and-depositional-features-of-glacial |
long_lat |
ENVELOPE(-70.000,-70.000,62.000,62.000) |
geographic |
Hudson Hudson Strait |
geographic_facet |
Hudson Hudson Strait |
genre |
Hudson Strait |
genre_facet |
Hudson Strait |
op_source |
Center for Coastal and Ocean Mapping |
op_relation |
https://scholars.unh.edu/ccom/1319 https://pubs.geoscienceworld.org/books/book/1195/chapter/11544076/erosional-and-depositional-features-of-glacial |
_version_ |
1766025918916067328 |