Description: During the "RV Polarstem"-Expedition ARK VIII/2 sediment samples were obtained at the continentalslope of NW-Spitsbergen. Detailed sedimentological and geochemical analysis were carriedout at two undisturbed box cores (PS2122-1GKG, PS2123-2GKG) as well as two gravity cores(PS2122-1SL, PS2123-2SL). The following parameters were deterrnined: Organic carbon, nitrogenand carbonate contents, hydrogen index, stable isotopes, ice rafted debris, grain-size distribution andbiogenic opal. The main objective of this study was the reconstruction of paleoenvironmental changes off thenorthwest coast of Spitsbergen during the last glacial/interglacial-cycle, i.e., during the last about128.000 years.The results of the investigations can be summarized as follows:- During isotope stage 1 (Holocene) and 5.5 (Eemian Interglacial), light stable isotopes (8180: 3,4-2%0; 8BC: 0,26-0,5 %0), increased bioturbation, high content of planktonic foraminifera andbiogenic opal and low quantity of ice-rafted material, indicate seasonally ice-free conditions alongthe northwest coast due to the int1uence of the Westspitsbergen Current.- Additionally, the sediment characteristics of the middle of isotope stage 2 (Last Glacial Maximum)and at the end of stage 3 confirms an inflow of warmer Atlantic water. The highest production ofplanktonic and benthic foraminifera (N. pachyderma sin., Cassidulina teretis) (CaC03: 10 %) mayret1ect the expansion of the "Whalers Bay"-Polynya as a result of the int1uence of the WestspitsbergenCurrent. Presumably, occasionally open-ice conditions provide sufficient precipitation to buildupthe Svalbard/Barents Ice Sheet.- The time intervals for the glacier advances on Svalbard given by Mangerud et al. (1992), can becorrelated with increased accumulation of ice-rafted material in the sediments at the northwest coastof Spitsbergen. Especially during isotope stage 4 and at the beginning of the Last Glacial Maximum(isotope stage 2), a drastically increased supply of coarse terrigenous material occurs. The highaccumulation rate (0,18-0,21 g/cm2jky) of terrigenous organic carbon is indicated by high C/Nratios(until 16) and low hydrogen index (50 mg-HC/gC). In constrast to deep sea sediments in theFram-Strait (Hebbeln 1992), the glacier advance between 118.000 and 108.000 years B.P. ist documented in the continental slope sediments.- At the end of the Weichselian ice age, the deglaciation at the northwest coast starts with a typicalmelt-water signal in the stables isotope record (8180: 3,5 %0; 813C: -0,16 %0) and high contents ofgravel (6-13 %). The signal can be assigned to an event at the westcoast of Spitsbergen (core NP9039), dated to 14.500 years B.P. (Andersen et al. 1993).

Description: Three cores recovered off the northwest of Svalbard were studied with respect to glacial/interglacial changes of clay and bulk mineralogy, lithology and organic geochemistry. The cores cover the Late Quaternary Marine Isotope Stages (MIS) 6–1 (ca. 170,000 years) and are located in the vicinity of the Polar Front which separates the warm Atlantic water of the Westspitsbergen Current and the cold Polar Water of the Transpolar Drift. Globally driven changes in the paleoenvironment like the variable advection of warm Atlantic water into the Arctic Ocean can be distinguished from regional events by means of source mineral signatures and organic geochemistry data. In particular, a combination of high organic carbon and low carbonate contents, high C/N-ratios, a particular lithology and a distinct bulk and clay mineral assemblage can be related to Svalbard ice sheet developments between 23,000 and 19,500 14C years. This complex sediment pattern has been traced to the northwest of Spitsbergen as far north as 82°N. Additionally, the same signature has been recognized in detail in upper MIS 5 sediments. The striking similarity of the history of the Svalbard/Barents Sea Ice Sheet during the late and early/middle Weichselian is elaborated. Both sediment horizons are intercalated between biogenic calcite rich core sequences which contain the so-called “High Productivity Zones” or “Nordway Events” related to the increased advection of warm Atlantic water to the Arctic Ocean. This study provides further evidence that the meridional circulation pattern has been present during most of the Weichselian and that the ice cover was often reduced in the northeastern Fram Strait and above the Yermak Plateau. Our findings contradict the widely used reconstructions in modelling of the last glaciation cycle and reveal a much more dynamic system in the Fram Strait and southwestern Eurasian Basin of the Arctic Ocean.

Description: A total of five sediment cores from three sites, the Arctic Ocean, the Fram Strait and the Greenland Sea, yielded evidence for geomagnetic reversal excursions and associated strong lows in relative palaeointensity during oxygen isotope stages 2 and 3. A general similarity of the obtained relative palaeointensity curves to reference data can be observed. However, in the very detail, results from this high‐resolution study differ from published records in a way that the prominent Laschamp excursion is clearly characterized by a significant field recovery when reaching the steepest negative inclinations, whereas only the N–R and R–N transitions are associated with the lowest values. Two subsequent excursions also reach nearly reversed inclinations but without any field recovery at that state. A total of 41 accelerator mass spectrometry (AMS) 14C ages appeared to allow a better age determination of these three directional excursions and related relative palaeointensity variations. However, although the three sites yielded more or less consistent chronological as well as palaeomagnetic results a comparison to another site, PS2644 in the Iceland Sea, revealed significant divergences in the ages of the geomagnetic field excursions of up to 4 ka even on basis of uncalibrated AMS 14C ages. This shift to older 14C ages cannot be explained by a time‐transgressive character of the excursions, because the distance between the sites is small when compared with the size of and the distance to the geodynamo in the Earth's outer core. The most likely explanation is a difference of reservoir ages and/or mixing with old 14C‐depleted CO2 from glacier ice expelled from Greenland at site PS2644.