(Table 2) Uranium and thorium isotopic composition, activity ratios and ages of bivalvia shells in sediment core GIK14350, northern Germany

A new chemical procedure for cleaning marine carbonates was applied to remove detritus as well as metaloxide contaminations of marine shells from Eemian deposits and adjoining succession of a sediment core from Dagebüll, Schleswig- Holstein. Hence, one can significantly reduce the contamination with detrital uranium and thorium. Thermal ionisation mass spectrometry was applied to determine the uranium and thorium activities used for 230Th/U dating of these shells. At least ten samples of marine bivalves of five different core sections were analysed. Samples located below a five meter thick clay layer at 19-24 m yielded an average age of 132±18 ka. Shells located above the clays at 15-20 m depth were strongly influenced by percolating groundwaters of an open system. Therefore, a reliable dating of these samples was not possible.

Biochemical investigation of multicorer sediment profile PS74/109-2

To detect and track the impact of large-scale environmental changes in a the transition zone between the northern North Atlantic and the central Arctic Ocean, and to determine experimentally the factors controlling deep-sea biodiversity, the Alfred- Wegener-Institute for Polar and Marine Research (AWI) established the deep-sea long-term observatory HAUSGARTEN, which constitutes the first, and until now only open-ocean long-term station in a polar region. Virtually undisturbed sediment samples have been taken using a video-guided multiple corer (MUC) at 13 HAUSGARTEN stations along a bathymetric (1,000 - 4,000 m water depth) and a latitudinal transect in 2,500 m water depth as well as two stations at 230 and 1,200 m water depth within the framework of the KONGHAU project. Various biogenic sediment compounds were analyzed to estimate the input of organic matter from phytodetritus sedimentation, benthic activities (e.g. bacterial exoenzymatic activity), and the total biomass of the smallest sediment-inhabiting organisms (size range: bacteria to meiofauna).

Biochemical investigation of multicorer sediment profile PS74/113-2

To detect and track the impact of large-scale environmental changes in a the transition zone between the northern North Atlantic and the central Arctic Ocean, and to determine experimentally the factors controlling deep-sea biodiversity, the Alfred- Wegener-Institute for Polar and Marine Research (AWI) established the deep-sea long-term observatory HAUSGARTEN, which constitutes the first, and until now only open-ocean long-term station in a polar region. Virtually undisturbed sediment samples have been taken using a video-guided multiple corer (MUC) at 13 HAUSGARTEN stations along a bathymetric (1,000 - 4,000 m water depth) and a latitudinal transect in 2,500 m water depth as well as two stations at 230 and 1,200 m water depth within the framework of the KONGHAU project. Various biogenic sediment compounds were analyzed to estimate the input of organic matter from phytodetritus sedimentation, benthic activities (e.g. bacterial exoenzymatic activity), and the total biomass of the smallest sediment-inhabiting organisms (size range: bacteria to meiofauna).

Biochemical investigation of multicorer sediment profile PS74/118-2

To detect and track the impact of large-scale environmental changes in a the transition zone between the northern North Atlantic and the central Arctic Ocean, and to determine experimentally the factors controlling deep-sea biodiversity, the Alfred- Wegener-Institute for Polar and Marine Research (AWI) established the deep-sea long-term observatory HAUSGARTEN, which constitutes the first, and until now only open-ocean long-term station in a polar region. Virtually undisturbed sediment samples have been taken using a video-guided multiple corer (MUC) at 13 HAUSGARTEN stations along a bathymetric (1,000 - 4,000 m water depth) and a latitudinal transect in 2,500 m water depth as well as two stations at 230 and 1,200 m water depth within the framework of the KONGHAU project. Various biogenic sediment compounds were analyzed to estimate the input of organic matter from phytodetritus sedimentation, benthic activities (e.g. bacterial exoenzymatic activity), and the total biomass of the smallest sediment-inhabiting organisms (size range: bacteria to meiofauna).