Geochronology and palaeoenvironment of marine Quaternary deposits in Denmark: new evidence from northern Jutland

The degree of isoleucine epimerization in the benthic foraminiferal species Elphidium excavatum and Bulimina marginata have been measured in four bore holes, penetrating marine interglacial beds, from northern Jutland. The res ults of these analyses are compiled with results obtained from other sites in Denmark and the North Sea region, and four aminozones (AZs) have been er ected. AZ1 (aIle/Ile <0.05) include the Late Weichselian and the Holocene p art of the record. AZ2 (0.08-0.12) includes samples of last interglacial ag e. AZ3 (0.14-0.16) includes samples from sites that have been previously co rrelated with the Holsteinian, and marine isotope stage 7 age for this zone is suggested. An age close to 400 +/- 100 ka is assigned to AZ4 (0.21-0.26 ). AZ4 is recorded in corings at Skagen and Norre Lyngby, and includes the here defined Skagerrak Interglacial, which is tentatively correlated with m arine isotope stage 11. The Skagerrak Interglacial sediments are characterized by boreal lusitanian benthic foraminiferal faunas evidencing strong input of Atlantic water to the North Sea. These faunas are replaced by assemblages indicating cooler c onditions at least twice during this period. The sedimentation pattern in n orthern Jutland during this interglacial seems to be different from the sed imentation regimes in the same area at the classical Eemian sites and durin g the Holocene, which were characterized by large sediment input from the J utland Current. This difference may be attributed to a change in the geomet ry of the sedimentary basin through the later part of the Quaternary, which is a result of repeated periods of intense erosion in the confluence area of the Norwegian Channel ice stream. A strong influx of Atlantic water to t he North Sea during stage 11 has been suggested earlier, based on records f rom the Devil's Hole area. However, the correlation of this event to the cl assic biostratigraphic based schemes of northwest Europe is still problemat ic.