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The Norwegian Channel between Skagerrak, in the southeast, and the continental margin of the northern North Sea, in the northwest, is the result of processes related to repeated ice stream activity through the last 1.1 m yr. In such periods the Skagerrak Trough (700 m deep) has acted as a confluence area for glacial ice from southeastern Norway, southern Sweden and parts of the Baltic. Possibly related to the threshold in the Norwegian Channel off Jæren (250 m deep), the ice stream, on a number of occasions over the last 400 ka, inundated the coastal lowlands and left an imprint of NW‐oriented ice directional features (drumlins, stone orientations in tills and striations). Marine interstadial sediments found up to 200 m a.s.l. on Jæren have been suggested to reflect glacial isostasy related to the Norwegian Channel Ice Stream (NCIS). In the channel itself, the ice stream activity is evidenced by mega‐scale glacial lineations on till surfaces. As a result of subsidence, the most complete sedimentary records of early phases of the NCIS are preserved close to the continental margin in the North Sea Fan region. The strongest evidence for ice stream erosion during the last glacial phase is found in the Skagerrak. On the continental slope the ice stream activity is evidenced by the large North Sea Fan, which is mainly a result of deposition of glacial‐fed debris flows. Northwards of the North Sea Fan, rapid deposition of meltwater plume deposits, possibly related to the NCIS, is detected as far north as the Vøring Plateau. The NCIS system offers a unique possibility to study ice stream related processes and the impact the ice stream development had on open ocean sedimentation and circulation.

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JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. INSTAAR, University of Colorado andThe Regents of the University of Colorado, a body corporate, contracting on behalf of the University of Colorado at Boulder for the benefit of INSTAAR are collaborating with JSTOR to digitize, preserve and extend access to Arctic and Alpine Research.ABSTRACT Seventeen cirque basins containing Younger Dryas moraines were investigated at Stad and Vags0y, western Norway. Lithostratigraphic studies, '4C datings, and pollen analysis of lake sediments just outside one of the moraines show that the glacier developed 50 to 180 yr after the vegetation responded to the climatic deterioration at the Aller0d-Younger Dryas transition. At the same transition acidophilous humus plants like Juniperus and Ericales disappeared and the vegetation became dominated by Salix, Artemisia, and Caryophyllaceae. Unusual high pollen influx values during Younger Dryas are interpreted to be the result of high pollen deposition on the glacier subsequently transported into the lake by the meltwater stream. An additional factor was the large amount of Salix growing in the immediate vicinity.The distribution of cirque moraines and equilibrium-line altitudes suggest that prevailing, snow-bearing winds during Younger Dryas came from southwestern directions. The Younger Dryas equilibrium line was about 700 m below the present. Correlations with marine geological results from adjacent seas indicates that an open North Atlantic and southern Norwegian Sea were the main precipitation sources for Younger Dryas glaciers. It is also suggested that the heaviest precipitation in Norway during Younger Dryas was in the Bergen-Nordfjord region, with increasing continentality both to the north and south.

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