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The Jæren lowland is located on the southwestern coast of Norway between a mountainous region in the east and the offshore Norwegian Channel in the west. During the Last Glacial Maximum, Jæren was in an intermediate position between an ice stream following the Norwegian Channel northwards, and westward flowing inland ice. The dynamic behaviour of the inland ice and the interaction with the ice stream are examined by means of geomorphological analysis of digital terrain models and sedimentological investigations. SW-trending drumlins were formed at Jæren below tributary ice from the inland, feeding into the Norwegian Channel Ice Stream. The presence of Rogen moraine in the central part of Jæren indicates a frozen substratum prior to their formation, and this suggests a transition to cold-based ice between the tributaries. The deglaciation of the Norwegian Channel at about 15 ka BP resulted in an unstable ice front for the inland ice sheet. The formation of Rogen moraine may be explained by a dynamic advance resulting in extensional flow and fracturing of the frozen substratum between the tributaries. The dynamic advance was followed by an early deglaciation of the coastal areas as evidenced by shallow marine sediments. Deformation of the shallow marine sand indicates a glacial readvance through the valleys formerly acting as tributaries to the ice stream. [ABSTRACT FROM AUTHOR]

Foraminiferal biostratigraphy, stable isotopes and amino-acid diagenesis have been investigated in a 125 m (+1 to -124 m a.s.l.) long core from Jæren, southwestern Norway. Two marine units, the 42m thick Grødeland Sand and the 8 m thick Sunde Sand, were found between till beds. Based on the biostratigraphic data, nine foraminiferal assemblage zones are defined. The Grødeland Sand showsa development from an ice-proximal glacial environment in the lower part, through an arctic, possibly shallow-water, environment, into a full interglacial open-shelf regime (the Grødeland Interglacial).The Grødeland Interglacial sediments (zone 6 Cassidulina laevigata-Cibicides zone) were deposited at a water depth of 20 m, in an open, high-energy shelf environment with temperature conditions similarto those prevailing in the northern North Sea today. The interglacial sediments are followed by deposits characteristic of an arctic environment which become more ice proximal upwards. Superimposed on theGrødeland Sand is a diamicton interpreted as till. Above the till is the upper marine unit (the Sunde Sand), which in the lower part yielded a shallow-water arctic fauna replaced upwards by an ice-proximalfacies. The upper part of the Sunde Sand is barren of foraminifera and is superimposed by an upper till. The Sunde Interstadial is defined as a climatostratigraphic event resulting in deglaciation of westernNorway and deposition of the Sunde Sand. Based on amino acid geochronology and inferences from the biostratigraphy, the Grødeland Interglacial is assigned to oxygen-isotope stage 7, whereas the SundeInterstadial is assigned to the Early Weichselian. Combined with existing data from the North Sea region and the Norwegian Sea, it is concluded that for stage 7, in addition to stages 1 and 5e, there musthave been a strong influx of Atlantic water into the Norwegian Sea north of the British Isles. This circulation created a similar north-... [ABSTRACT FROM AUTHOR]