Quaternary erosion in the Sognefjord drainage basin, western Norway
Abstract
The preglacial (paléic) landscape configuration in the Sognefjord drainage basin of western Norway is reconstructed, and the total Quaternary erosion is quantitatively determined to 7610 km 3 by subtracting the present topography from the reconstructed preglacial surface. With an average erosion of 610 m during the suggested time span of 600,000 yr when Scandinavian ice sheets reached the continental shelf off western Norway, mean Quaternary erosion rates are calculated to ca. 1.02 mm/yr. Using the average relief of 2000 m along the fjord, however, the rate of glacial erosion was 3.3 mm/yr. Taking into account the selective nature of glacial erosion by ice streams along the fjord, an estimate of 2 ± 0.5 mm/yr is likely. Limited to the east by the main watershed, a rough estimate of the total Quaternary glacial erosion in the fjord region of western Norway is calculated to about 35,000 km 3 of rock. With a soft-sediment porosity of 30-50%, this corresponds to about 45,500-52,500 km 3 of continental shelf/deep-sea sediments.
- Publication:
-
Geomorphology
- Pub Date:
- September 1992
- DOI:
- 10.1016/0169-555X(92)90022-G
- Bibcode:
- 1992Geomo...5..511N