(Table 6a) 137Cs concentrations in waters of the Sea of Japan in 1994 and in 2002

Sulfide, S°, and thiosulfate were determined in waters of the Baltic Sea. Microquantities of these compounds were observed in oxic waters. Concentration levels of reduced sulfur compounds in Baltic oxic waters were very close to levels of the Black Sea oxic zone. Thiosulfate and S° were predominate compounds in oxic water whereas sulfide was a predominant compound Baltic waters high in hydrogen sulfide. Conclusion was made that during sedimentation in oxic waters anaerobic microorganisms along with aerobic bacteria take part in mineralization of organic matter. They exist on surfaces and in microniches of particles of organic detritus.

(Table 6b) 137Cs concentrations in surface layer bottom sediments of the Sea of Japan in 1994 and in 2002

Sulfide, S°, and thiosulfate were determined in waters of the Baltic Sea. Microquantities of these compounds were observed in oxic waters. Concentration levels of reduced sulfur compounds in Baltic oxic waters were very close to levels of the Black Sea oxic zone. Thiosulfate and S° were predominate compounds in oxic water whereas sulfide was a predominant compound Baltic waters high in hydrogen sulfide. Conclusion was made that during sedimentation in oxic waters anaerobic microorganisms along with aerobic bacteria take part in mineralization of organic matter. They exist on surfaces and in microniches of particles of organic detritus.

(Table 1) Biomass of plankton in the Sea of Japan at Station VITYAZ6674

Vertical distribution of zooplankton biomass from the surface to bottom layers (3400 m) is examined. Material was collected layer by layer by a BR 113/140 net at 41°59' N and 133°37' E on July 2 and 3, 1970. Quantity of plankton below 1000 m was found to be much less than at corresponding depths in the adjacent regions of the ocean. This impoverishment is due to absence of oceanic bathypelagic animals in deep layers of the Sea of Japan. Absence of specialized predators (plankton-feeders) deep in the Sea of Japan results in underconsumption of interzonal animals that sink to great depths. Upon dying they should reach the floor in larger quantities than in the ocean.

Concentration of phenols in bottom sediments from the Kandalaksha Bay, White Sea

Data on distribution of organic carbon and phenols near the top of Kandalaksha Gulf, one of the largest gulfs of the White Sea, are presented. Investigations carried out the port city of Kandalasksha indicate that bottom sediments of the area adjoining the port contain synthetic phenols and have elevated concentrations of organic carbon. But in general sediments of this part of the gulf have near-normal concentration and composition of both phenols and organic carbon. This indicates that ecological situation in this area remains near-optimal.

Alkenones and sea surface reconstruction of sediments from, the Arabian Sea

Deep-sea sediments of two cores from the western (TY93-929/P) and the southeastern (MD900963) Arabian Sea were used to study the variations of the Indian monsoon during previous climatic cycles. Core TY93-929/P was located between the SW monsoon driven upwelling centres off Somalia and Oman, which are characterized by large seasonal sea surface temperature (SST) and particle flux changes. By contrast, core MD900963, was situated near the Maldives platform, an equatorial ocean site with a rather small SST seasonality (less than 2°C). For both cores we have reconstructed SST variations by means of the unsaturation ratio of C37 alkenones, which is compared with the delta18O records established on planktonic foraminifera. In general, the SST records follow the delta18O variations, with an SST maximum during oxygen isotope stage 5.5 (the Last Interglacial at about 120-130 kyr) and a broad SST minimum during isotope stage 4 and 3.3 (approximately 40-50 kyr). The SST difference between the Holocene and the Last Glacial Maximum (LGM) is of the order of 2°C. In both cores the SSTs during isotope stage 6 are distinctly higher by 1-2°C than the cold SST minima during the last glacial cycle (LGM and stage 3). To reconstruct qualitatively the past productivity variations for the two cores, we used the concentrations and fluxes of alkenones and organic carbon, together with a productivity index based on coccolith species (Florisphaera profunda relative abundance). Within each core, there is a general agreement between the different palaeoproductivity proxies. In the southeastern Arabian Sea (core MD900963), glacial stages correspond to relatively high productivity, whereas warm interstadials coincide with low productivity. All time series of productivity proxies are dominated by a cyclicity of about 21-23 kyr, which corresponds to the insolation precessional cycle. A hypothesis could be that the NE monsoon winds were stronger during the glacial stages, which induced deepening of the surface mixed layer and injection of nutrients to the euphotic zone. By contrast, the records are more complicated in the upwelling region of the western Arabian Sea (core TY93-929/P). This is partly due to large changes in the sedimentation rates, which were higher during specific periods (isotope stages 6, 5.4, 5.2, 3 and 2). Unlike core MD900963, no simple relationship emerges from the comparison between the delta18O stratigraphy and productivity records. The greater complexity observed for core TY93-929/P could be the result of the superimposition of different patterns of productivity fluctuations for the two monsoon seasons, the SW monsoon being enhanced during interglacial periods, whereas the NE monsoon was increased during glacial intervals. A similar line of reasoning also could help explain the SST records by the superimposition of variations of three components: global atmospheric temperature, and SW and NE monsoon dynamics.

Composition of bitumen in the organic matter of Black Sea sediments from DSDP Hole 42-379B

Bituminologic analysis of sediment cores from the Black Sea (water depth up to 2000 m, drilling depth up to 625 m) has revealed all components typical for fossilized rocks, viz. hydrocarbons, resins, asphaltenes, and insoluble matter. Proportions of these components, their composition and properties do not display any dependence on depth in hole and seem to be governed by composition of organic matter and conditions and degree of its transformation at early stages of lithogenesis.

Investigation of sediment core PS2556 from Bellingshausen Sea, Antarctica

Die Rekonstruktion der glaziomarinen Sedimentationsprozesse am antarktischen Kontinentalrand des westlichen Bellingshausenmeeres erfolgte durch die sedimentologische Auswertung eines 962 cm langen Schwerelotkernes aus 3594 m Wassertiefe. Der Kern wurde während des Fahrtabschnittes ANT-XI/3 mit dem FS "Polarstern" vom Scheitel einer Sediment- "Drift" gezogen. An dem Sedimentkern wurde eine lithologische Beschreibung, sowie sedimentologische Untersuchungen und sedimentphysikalische Messungen durchgeführt. Anhand der Ergebnisse konnten signifikante Änderungen in der Zusammensetzung und Struktur der Sedimente erkannt, und drei Faziestypen unterschieden werden. Die Faziestypen charakterisieren jeweils glaziale oder interglaziale Zeiträume. Der größte Teil der Sedimentabfolge gehört der Laminitfazies an. Dabei handelt es sich um feinlaminierte Sedimentabschnitte, die vorwiegend aus feinkörnigen, terrigenen Komponenten zusammengesetzt sind. In die feinlaminierten Abschnitte sind vereinzelte, wenige Milimeter bis Zentimeter mächtige Siltlagen eingeschaltet. Die biogenen Anteile sind gering, Anzeichen für Bodenleben fehlen völlig. Die Manganfazies wird von authigen gebildeten Mangankonkretionen dominiert, die jeweils diskrete Lagen bilden. Dabei handelt es sich zum einen um Mikromanganknollen und -krusten und zum andern um manganhaltige Gangfüllungen. Biogene und terrigene Anteile sind in diesem Faziestyp unbedeutend. Die Biogenfazies ist von strukturlosen und stark bioturbierten Sedimenten gekennzeichnet. In diesen Sedimentabschnitten ist der hohe Anteil an Eisfracht (IRD) und die erhöhten Gehalte an Kalziumkarbonat und Opal in der Sandfraktion markant. Die stratigraphische Einordnung des Sedimentkernes erfolgte über die von Grobe & Mackensen (1992) entwickelte Lithostratigraphie, mit deren Einheiten die Faziestypen des Sedimentkernes korreliert werden konnten. Dabei ergaben sich zwei mögliche Altersmodelle und ein Basisalter von ca. 250.000 Jahren. Anhand der stratigraphischen Fixpunkte wurden Sedimentationsraten des Gesamtsedimentes und Akkumulationsraten des Kalziumkarbonates, des Biogenopals und des organisch gebundenen Kohlenstoffes berechnet. Dabei wurde gezeigt, daß lediglich das Kalziumkarbonat und der Biogenopal als Anzeiger für biologische Produktion dienen können, wobei Lösungsprozesse in der Wassersäule und im Sediment eine große Rolle spielen. Der Gehalt an organisch gebundenem Kohlenstoff ist in dem Sedimentkern nur erhaltungsbedingt zu erklären. Die Sedimentationsprozesse der einzelnen Faziestypen sind von den Eisverhältnissen, der biologischen Produktion, dem gravitativen Transport und der Umlagerung durch Meeresströmungen abhängig. Die Auswirkung der einzelnen Faktoren ist jeweils unterschiedlich ausgeprägt und wirkt sich spezifisch auf die einzelnen Parameter aus. In den Glazialen hatte ein Vorstoß des Schelfeises über die Schelfkante zur Anlieferung großer Sedimentmassen geführt, die über gravitativen Transport den Kontinentalhang hinunter transportiert wurden. Die Feinfracht wurde über parallel zum Kontinentalhang laufende Konturströme westwärts transportiert und in der Larninitfazies der Driftkörper abgelagert. Am Ende der Glaziale kam es zur Sedimentation der Manganfazies. Die geringen Sedimentationsraten am Kamm der Sedimentdrift kamen aufgrund reduzierter Intensität der Konturströme und fehlender Umlagerung von Schelfsedimenten in Folge rückschreitender Schelfeisrnassen zustande. In den Interglazialen kam es durch den aufsteigenden Meeresspiegel zum Aufschwimmen des Schelfeises. Der damit verbundene Abbau der Eisrnassen über dem Schelf, hatte eine hohe Sedimentation von IRD zur Folge. Mit fortschreitendem Interglazial kam es in Zeiten nur saisonaler Meereisbedeckung zu verstärkter biologischer Produktion und zur Sedimentation biogenen Materials.

Distribution of Upper Cretaceous deep water agglutinated foraminifera in sediments of the North Atlantic and its marginal seas (Tab. 1)

The stratigraphic and biogeographic distribution of more than 170 species of deep-water agglutinated benthic foraminifers (DWAF) from the North Atlantic and adjacent marginal seas has been compared with paleoenvironmental data (e.g. paleobathymetry, oxygenation of the bottom waters, amount of terrigenous input and substrate disturbance). Six general types of assemblages, in which deep water agglutinated taxa occur, are defined from the Turonian to Maastrichtian times: 1. High latitude slope assemblages 2. Low to mid latitude slope assemblages 3. Flysch-type assemblages 4. Deep water limestone assemblages (,,Scaglia,,-type) 5. Abyssal mixed calcareous-agglutinated assemblages 6. Abyssal purely agglutinated assemblages Latitudinal differences in faunal composition are observed, the most important of which is the lack or extreme paucity of calcareous forms in high latitude assemblages. East-to-west differences appear to be of comparatively minor importance. Most DWAF species occur in all studied regions and are thus considered as cosmopolitan. Biostratigraphic turnovers in the taxonomic content of assemblages are observed in the lowermost Turonian, mid-Campanian and in the upper Maastrichtian to lowermost Paleocene. These datum levels correspond to inter-regional and time-constant paleooceanographic events, which probably also affected the deep-water benthic biota. This allows us to use deep-water agglutinated foraminifers for biostratigraphy in the North Atlantic sequences deposited below CCD and to geographically extend the currently used zonal schemes which have been established in the Carpathian and Alpine areas.

Sedimentology of cores from the Bellingshausen Sea, Antarctic

On the continental rise west of the Antarctic Peninsula there are nine large mounds interpreted as sediment drifts, separated by turbidity current channels. Drift 7 is 150 km long, 70 km wide and up to 700 m high and is asymmetric, with steep sides on the south-east (towards the continent) and south-west, and gentle slopes to north-west and north-east. Cores on the gentle sides of the drift show a cyclicity between brown, bioturbated, diatom-bearing mud with foraminifera and radiolarians, and grey, laminated, barren mud. Biostratigraphic evidence is consistent with a Late Quaternary age. Detailed lithostratigraphy and magnetic susceptibility data allow precise correlation over distances of tens of kilometres. On the basis of chemostratigraphy, the brown sediment is interpreted as interglacial (isotope stages 1 and 5) and the grey as glacial (stages 2-4 and 6). Sedimentation rates are 3.0-5.5 cm/ka. Cores on the steep sides of the drift recovered a condensed section with thinner cycles and hiatuses. Fine grain size, very poor sorting and the absence of a mode in the silt size range indicate deposition from suspension with only weak current activity, There is little evidence for cyclic changes in bottom current strength. Supply of sediment to the benthic nepheloid layer was by entrainment ofmud from turbidity currents, and by settling ofpelagic material (biogenic grains, IRD, sediment suspended in meltwater plumes). Cyclic changes in sediment supply include more biogenic supply in interglacials with less sea ice cover, more terrigenous supply from turbidites in glacials with ice sheets grounded to the shelf edge, and changes in IRD content.