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Sedimentological and geochemical (XRF) data together with information from diatom and benthic foraminiferal records of a 3.5 m long gravity core from Ameralik Fjord, southern West Greenland, is used for reconstructing late-Holocene environmental changes in this area. The changes are linked to large-scale North Atlantic ocean and climate variability. AMS 14 C-dating of benthic foraminifera indicates that the sediment core records the last 4400 years and covers the termination of the Holocene Thermal Maximum (HTM). The late HTM (4.4 Á3.2 ka BP) is characterized by high accumulation rates of fine (silty) sediments related to strong meltwater discharge from the Inland Ice. The HTM benthic foraminiferal fauna demonstrates the presence of well-ventilated, saline bottom water originating from inflow of subsurface West Greenland Current water of Atlantic (Irminger Sea) origin. The hydrographic conditions were further characterized by limited sea ice probably related to a mild and relatively windy winter climate. After 3.2 ka BP lower fine-grained sedimentation rates, but a larger input from sea-ice rafted or aeolian coarse material prevailed. This can be related to colder atmospheric conditions with a decreased meltwater discharge and more widespread sea-ice cover in the fjord.

Abstract. Five gravity cores taken from the Reykjanes Ridge have been used to establish a link between sediment physical properties and atmospheric records documented by 5•aO variations in Greenland ice cores over the last 45,000 calendar years. Marine Gamma Ray Attenuation Porosity Evaluator density and magnetic susceptibility variations could be linked with the ice core Dansgaard-Oeschger and Bond cycles. This is supportedby ice-rafted detrl'tUs (IRD), grain size, the quartz/feldspar ratio, and carbonate, isotopic, and f6raminiferal records. The covariation of the sediment physical properties and •5•aO in Greenland ice indicates a coupling of atmospheric temperature and paleocirculation variations. Gradual reduced bottom currents (Iceland-Scotland Overflow Water) and enhanced iceberg discharges have been reconstructe. d fo.r cold atmospheric periods relative to interstadial times. In. the study area_the magnetic susceptibility signal is not relatecl to the ice-rafted detritus input but most probably reflects the variations oI-the IceIand-Scotland Overflow Water intensity transporting titanomagnetlte into the R(,•ykjanes Ridge region.

2002 (June): Regressions and transgression s of the Baltic basin re ected by a new high-resolutio n deglacia l and postglacia l lithostratigraphy for Arkona Basin sediments (western Baltic Sea). Boreas, Vol. 31, Seismoacoustic pro les from the Arkona Basin show a late Pleistocene and Holocene successio n of several distinct re ectors. The physical , sedimentological , mineralogical and geochemica l propertie s of more than 30 sediment cores were analysed in order to assign these re ectors to speci c sedimentar y discontinuit y layers. Additionally , AMS 14 C data and biostratigraphi c information were gathered . Based on this multi-proxy approach, seven lithostratigraphi c units (AI, AII, B to F) were distinguished . These consist of ne-grained clay, silt and mud, and are separate d from each other by thin basin-wide traceable sandy layers (S ab -S ef ). The most sensitive parameter to mark the lithostratigraphi c boundarie s is the weight percentag e of the grain-siz e fraction >63 mm. In addition, some of the quartz-grain-dominate d sandy layers cause the strong re ection lines recorded in seismoacousti c pro les. The sandy layers are interpreted to re ect enhanced hydrodynami c energy induced by episodes of basin-wide water-level low-stand conditions. These low stands resulted from waterlevel drops that occurred frequentl y during the Baltic Sea's history and presumably affected the entire Baltic basin. The thick ne-graine d units AI, AII to F, in which coarser material is absent, represen t water-level high-stands . We conclude that the units AI and AII are Baltic Ice Lake sediments deposite d before and after the Billingen-1 regression , respectively . We assign the most prominent sandy layer S ab to the nal drainage of the Baltic Ice Lake (Billingen-2) , whereas the sandy layers between units B, C, D and E are related to the Yoldia Sea and Ancylus Lake regression s of the Baltic Sea's history. The uppermost ne-grained unit F with its high organic carbon content contains marine sediments deposite d after the Littorina Transgression . The macroscopicall y well-visible sediment colour change from reddish/brown-to-grey , previousl y interprete d as a regional stratigraphi c boundary, varies from core to core. It has been shown by our new data that this colour change has a diagenetic origin, and thus does not represent a stratigraphi c boundary. Previous subdivision s therefore have to be revised.