Title | Submarine landslides triggered by iceberg collision with the seafloor |
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Author | Normandeau, A ;
MacKillop, K; Macquarrie, M; Richards, C; Bourgault, D; Campbell, D C ; Maselli, V ; Philibert, G; Hughes Clarke, J |
Source | Nature Geoscience 2021 p. 1-17, https://doi.org/10.1038/s41561-021-00767-4 |
Year | 2021 |
Alt Series | Natural Resources Canada, Contribution Series 20200001 |
Publisher | Springer Nature |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf |
Province | Nunavut |
NTS | 16L/09; 16L/16 |
Area | Southwind Fiord; Baffin Island |
Lat/Long WENS | -62.5000 -62.0000 67.0000 66.6167 |
Subjects | marine geology; surficial geology/geomorphology; geophysics; Nature and Environment; Science and Technology; continental margins; continental slope; marine environments; landslides; iceberg gouging;
geophysical surveys; acoustic surveys, marine; bathymetry; marine sediment cores; sediment stability; remote sensing; satellite imagery; stress analyses; slope stability; slope failures; Last Glacial Maximum; Infrastructures; Climate change;
cumulative effects; Phanerozoic; Cenozoic; Quaternary |
Illustrations | location maps; geoscientific sketch maps; profiles; block diagrams; geochronological charts; satellite images; photographs; plots |
Program | Public Safety Geoscience Assessing landslides and marine geohazards |
Program | Program of Energy Research and Development (PERD) |
Released | 2021 06 24 |
Abstract | Iceberg discharge influences ocean circulation, affects climate and increases global sea level. Icebergs are also known to gouge the seafloor in water depths limited by their keel depth, thus
representing a hazard to subsea infrastructure. Here, we provide evidence that icebergs can affect the seafloor at depths greater than their keel depth by triggering submarine landslides. Using repeat bathymetric surveys from multibeam echo sounders,
we investigate the cause of a submarine landslide that occurred in Southwind Fjord, Baffin Island, between September 2018 and September 2019. This landslide is shown to be closely associated with recently formed iceberg pits at its headscarp carved
by an iceberg that grounded and that capsized in the fjord in early September 2018. Geotechnical data from a nearby sediment core indicate that the vertical loading induced by the iceberg grounding and capsizing is sufficient to trigger the observed
landslide. These results imply that icebergs originating from the Arctic, Greenland and Antarctica are hazards thousands of kilometres away from their original source and can affect continental slopes by triggering submarine landslides. This process
represents an additional source of marine geohazards, especially if climate change leads to increased iceberg discharge. |
Summary | (Plain Language Summary, not published) We show that a new submarine landslide was triggered in Southwind Fiord, Baffin Island, in September 2018. This new landslide was triggered by the
vertical loading induced by an iceberg grounding. These results imply that icebergs originating from Greenland and Antarctica are hazards thousands of kilometres away from their original source and can affect the entire depth range of continental
slopes by triggering submarine landslides. |
GEOSCAN ID | 322195 |
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