A CLIMATIC RECORD FOR THE LAST 12,000 YEARS FROM A SEDIMENT CORE ON THE MID-NORWEGIAN CONTINENTAL-SHELF

The local depositional environment in Late Weichselian and Holocene time is inferred from investigations including sedimentology, geotechnical properties, biostatigraphy, stable isotopes and radiocarbon dates from a 265 cm long vibrocorer sample from 165 m water depth at 64-degrees-59'N and 9-degrees-14'E. The lower part of the core is interpreted to be extensively remoulded by iceberg scouring, while the top 160 cm gives a continuous record fo the last 12,000 years. Three radiocarbon dates and a volcanic ash zone (Vedde Ash Bed) provide ages ca. every 600 years for the period 12,000 to 10,000 years BP. Minimum content of boreal foraminifera (representing the most arctic conditions) occurred from before 12,000 to about 11,800 and from 11,000 to 10,400 years BP. The transition from arctic to boreal conditions is very marked at about 10,300 +/- 200 years BP. Later minima of boreal foraminifera (colder events) are recorded around 10,000 to 9000 years BP, with variation shorter than the time resolution. The core provides a detailed record during the deglaciation period of Scandinavia after 12,000 years BP, and shows good correlation to land data. The upper part of the core, representing the last 9000 years, shows maximum content of the boreal Trifarina angulosa (optimal climatic conditions) around 5000 years BP and then decreasing values up to present time.