Late Weichselian depositional processes, £uxes, and sediment volumes on the margins of the Norwegian Sea (62^75‡N)
Quaternary continental margin sedimentation in the Norwegian^Greenland Sea has been a response to a combination of tectonic, oceanographic, and glacial activity. Using geophysical survey data (6.5 kHz side-scan sonar and 3.5 kHz penetration echo sounding), in association with bathymetric datasets, t...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Text |
| Language: | English |
| Published: |
2002
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| Subjects: | |
| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.596.2647 http://www.cpom.org/research/mjs-marine1.pdf |
| Summary: | Quaternary continental margin sedimentation in the Norwegian^Greenland Sea has been a response to a combination of tectonic, oceanographic, and glacial activity. Using geophysical survey data (6.5 kHz side-scan sonar and 3.5 kHz penetration echo sounding), in association with bathymetric datasets, the magnitude and frequency of the main forms of margin sedimentation into the Lofoten and Norwegian Basins of the Norwegian Sea during the Late Weichselian and Holocene are estimated. By comparing these geophysically determined estimates of sediment fluxes with numerically modelled ice-sheet sediment delivery, the role of ice-sheets in shaping the processes acting on this margin is assessed. Sediment flux at the shelf edge during the Late Quaternary is dominated by ice-sheet delivery of sediments, focused at the mouths of fast-flowing ice streams formed in bathymetric troughs. Interglacials are, by contrast, characterised by comparatively little sediment accumulation. Submarine fans, at the margins of cross-shelf troughs, are major depocentres on this glacier-influenced margin. However, occasional large-scale failures of the continental slope account for approximately 75 % of the basin sediment accumulation during the past 30 000 yr, by eroding substantial quantities of pre-Quaternary deposits. Trough mouth fan and a combination of hemipelagic and glacimarine processes are responsible for the accumulation of the remaining 15 % and 7 % of basin sediments |
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