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During the last c. 2.7 M.y. large quantities of glacially-derived material were transported westwards from the Norwegian mainland and inner shelf areas and deposited mainly as prograding sediment wedges into a basin of intermediate depth offshore of mid-Norway. The deposits are more than 1000 m thick in extensive areas, and the shelf edge migrated up to 150 km westwards. The 800 km-long Norwegian Channel, which hosted ice streams through many glaciations and which drained most of southern Norway and parts of central Sweden, was initiated c. 1.0- 1.5 million years ago. Over 1500 m of glacigenic sediments were deposited at the mouth of this channel as the North Sea Fan, of which 400 m accumulated during the last glaciation (the Weichselian). Several huge slope failures have occurred on the outer shelf/upper slope and appear to be related to the sedimentation pattern (and timing) of the glacial-interglacial cycles. About 100 000 km3 of shelf sediments were deposited on the mid-Norwegian shelf between 63°N and 68°N (c. 160 000 km2) during late Pliocene/ Pleistocene. This equals an average erosion of 450 m of the corresponding denudation area (c. 160 000 km2) over the inner shelf areas and the land areas of Norway eastwards to the main water divide. The average erosional rate increased from the first 1-2 m.y. to the last 0.5 m.y. by a factor between 2 and 3. Although the chronology of the oldest mapped sequences is poorly constrained, it appears that the average erosion rate at least doubled during the last 0.5-1.0 million years compared to the first c. 2 m.y. of the last Ice Age
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