(Table 1.4) Ratios of petrogenic components in glassy and crystalline basalts from the north part of the Bougault anomaly, Mid-Atlantic Ridge 15°N

Structure and composition of sub-surface bottom sediments from the southwest Barents Sea have been under study. The study has revealed heterogeneity of sediment structure resulted from temporal irregularity and variability of sedimentation processes. The study of the heavy minerals from 0.1-0.01 mm grain size fraction has shown prevalence of green hornblende, epidote, garnet, and ilmenite in all types of sediments; these minerals are the basis of terrigenous-mineralogical province. At the same time in different areas local terrigenous-mineralogical associations have been identified. Clay mineral composition of in the sediments was quite uniform: biotite, chlorite, hydromica, smectite. Despite this, a number of features indicating initial stages of clay mineral transformation has been identified. Differences in material composition and structure of the studied sediments are associated with rapid change in paleogeographic situation on the land - ice cover melting on the Kola Peninsula and subsequent Holocene climatic situation.

(Table 1.5) Contents of some volatile components in glassy MORB from the north part of the Bougault anomaly, Mid-Atlantic Ridge 15°N

Structure and composition of sub-surface bottom sediments from the southwest Barents Sea have been under study. The study has revealed heterogeneity of sediment structure resulted from temporal irregularity and variability of sedimentation processes. The study of the heavy minerals from 0.1-0.01 mm grain size fraction has shown prevalence of green hornblende, epidote, garnet, and ilmenite in all types of sediments; these minerals are the basis of terrigenous-mineralogical province. At the same time in different areas local terrigenous-mineralogical associations have been identified. Clay mineral composition of in the sediments was quite uniform: biotite, chlorite, hydromica, smectite. Despite this, a number of features indicating initial stages of clay mineral transformation has been identified. Differences in material composition and structure of the studied sediments are associated with rapid change in paleogeographic situation on the land - ice cover melting on the Kola Peninsula and subsequent Holocene climatic situation.

(Table 1) Mean sea-ice properties from moored upward looking sonars along the Greenwich meridian

Sea-ice ocean interaction processes are of significant influence on the water mass formation in the Weddell gyre. On the basis of data obtained between 1984 and 2008 from eight repeat hydrographic sections, moored instruments and profiling floats in the Weddell gyre on the Greenwich meridian - almost all of them collected with R.V. Polarstern - we identified variations in the properties of the Winter Water and the sea ice draft. In the Winter Water the salinity was relatively low throughout the 1990s (with a minimum in 1992) and a maximum was observed in 2003. Observations of sea ice draft by moored upward looking sonars are available from 1996 onwards. In the southern part of the transect they display variations on a decadal time scale with a minimum in sea-ice thickness in 1998 and an increase since then. Salinity variations in the Winter Water layer cannot be explained only by variations in sea-ice formation and variable entrainment of underlying Warm Deep Water, but lateral advection of water and sea ice needs to be taken into account as well. Potential sources are melt water from the ice shelves in the western Weddell Sea or transport of water of low salinity entering the Weddell gyre from the east. Accompanying variations of the properties of Warm Deep Water are discussed in detail in a companion paper (Fahrbach et al., 2011, doi:10.1016/j.dsr2.2011.06.007).

Description and chemical composition of manganese nodules during R/V "Tyro" cruise APNAP 1 to the Madeira Abyssal Plain in 1986

The porewater and sediment composition of two boxcores and of a small gravity core, taken on a manganese-nodule-covered hill and in the Madeira Abyssal Plain proper respectively, are compared. The pore-water study of the two boxcores indicates that oxic conditions prevail in both cores. In addition, it indicates that no detectable fluxes of Mn or Fe occur from the porewater to the ocean bottom water. Variations in the geochemical composition of the sediments can be explained by fluctuations in the amount of carbonate, which acts as a diluting agent. A clear carbonate minimum is observed at 20-22 cm depth in the two cores. This minimum is likely to be associated with the last glacial period (10-20 kyr B.P.). This association is supported by the sediment accumulation rate of 15 mm/kyr as found by extrapolation from the rate for pelagic sediments in the Madeira Abyssal Plain. The bulk composition of the manganese nodules recovered from the submarine hill is chemically almost identical to the average composition of Atlantic nodules. The trace metal and Rare Earth Elements composition indicate a hydrogenous origin for the manganese nodules of this study. On the basis of the chemical composition, and that of nodules relative to that of the adjacent sediments, an average nodule accretian rate of 2.8-3.3 mm/myr has been calculated. Although the analyses of the entire ferromanganese nodules that have been studied seem to indicate a homogenous composition, internal structures of the nodules reveal great inhomogeneity, both visually and chemically. These fluctuations may be related to variations in the fluxes of Mn and Fe, which in turn could be climate-related.

Planktonic foraminifera in ODP Hole 112-688A (Table 1)

Species of Globorotalia are among the most dissolution-resistant planktonic foraminifers in sediments of the inner wall of the Middle America Trench; parts of their Phylogenetic history have been recognized in sediments of Leg 107 (Glacon and Bourgois, 1985). These species can be integrated into the biostratigraphic scheme on the basis of calcareous and siliceous nannoplankton and calibrated on the basis of paleomagnetism (Keller, 1980, 1981; Keller et al., 1982; Barron and Keller, 1982). Data compiled for this data report extend to the southern area of occurrence of Globorotalia species. About 250 sediment samples were collected on board JOIDES Resolution and examined as follows: 20-cm**3 samples were dried for 8 hr at 60°C, weighed, and then washed through sieves of 0.5, 0.2, 0.125, and 0.063 mm mesh size. The residues were dried and reweighed. The abundance of planktonic foraminifers counted is reported as numbers of specimens per weight of the original sample.

(Table 1) Concentrations of particulate organic carbon in the South Atlantic in February-March 1989

On the basis of 332 analyses of dissolved (DOC) and particulate organic carbon (POC) in samples collected from the surface to 4785 m depth at 10 stations in the atlantic part of the Antarctic Ocean the following regularities were observed: low DOC concentration, a sharp decrease in upper 40-120 m, small changes deeper in the water column, decrease in concentrations in the Antarctic divergence zone, absence of a correlation between DOC and primary production of plankton. Decrease in POC concentrations with depth when there is a small gradient in the 0-200 m water layer, increase in POC concentrations in the pycnocline and during phytoplankton bloom were found. As a whole the Antarctic Ocean is characterized by small POC concentrations close to average values for the world ocean. The nature of DOC and POC concentrations changes in the surface layers of the Indian and Atlantic oceans along the ship's route was considered.

Occurence of foraminifera and other microfossils in sediment core CRP-2/2A (Table 1)

Sparse to moderately abundant foraminiferal assemblages from Oligocene and Lower Miocene sediments in the CRP-2/2A drillhole contain C.27 genera and 42 species of calcareous benthic foraminifera. No planktic or agglutinated taxa were observed. On the basis of their faunal characteristics, four Foraminiferal Units are defined in drillhole succession: Foraminiferal Unit I (26.91-193.95 mbsf), mostly sparse assemblages with Elphidium magellanicum and Cribroelphidium sp.; Foraminiferal Unit II (193.95-342.42 mbsf), mostly moderately abundant assemblages with Cassidulinoides aequilatera and Eponides bradyi; Foraminiferal Unit III (342.42-486.19 mbsf), moderately abundant to sparse assemblages characterised by Cassidulinoides chapmani and Stainforthia sp.; and Foraminiferal Unit IV, Improverished (486.19-624.15, total depth, mbsf), with mostly barren residues, but with large Milioliidae recorded in situ at various horizons in the drill core. Foraminiferal Units I-IV lack taxa allowing correlation to standard zonal schemes. Inspection of faunal records from CIROS-1 and DSDP 270 indicates that, although the faunas show an overall similarity, CRP-2/2A Foraminiferal Units I-IV are not identifiable at these sites. The units are therefore most likely to reflect local environmental changes, and probably will prove useful for local correlation, but their lateral extent is undetermined. All four assemblages apparently represent various glacially-influenced shelf environments, and appear to reflect a long term deepening trend from Units IV to II, from perhaps inner to mid or outer-shelf depths, followed by a return to shallower, inner shelf, conditios for Unit I.

(Table 1) Seasonal sea ice concentration and the observed changes from 1972 to 2007 for the Southern Beaufort Sea

A reliable data set of Arctic sea ice concentration based on satellite observations exists since 1972. Over this time period of 36 years western arctic temperatures have increased; the temperature rise varies significantly from one season to another and over multi-year time scales. In contrast to most of Alaska, however, on the North Slope the warming continued after 1976, when a circulation change occurred, as expressed in the PDO index. The mean temperature increase for Barrow over the 36-year period was 2.9°C, a very substantial change. Wind speeds increased by 18% over this time period, however, the increase were non-linear and showed a peak in the early 1990s. The sea ice extent of the Arctic Ocean has decreased strongly in recent years, and in September 2007 a new record in the amount of open water was recorded in the Western Arctic. We observed for the Southern Beaufort Sea a fairly steady increase in the mean annual amount of open water from 14% in 1972 to 39% in 2007, as deduced from the best linear fit. In late summer the decrease is much larger, and September has, on average, the least ice concentration (22%), followed by August (35%) and October (54%). The correlation coefficient between mean annual values of temperature and sea ice concentration was 0.84. On a monthly basis, the best correlation coefficient was found in October with 0.88. However, the relationship between winter temperatures and the sea ice break-up in summer was weak. While the temperature correlated well with the CO2 concentration (r=0.86), the correlation coefficient between CO2 and sea ice was lower (r=-0.68). After comparing the ice concentration with 17 circulation indices, the best relation was found with the Pacific Circulation Index (r=-0.59).

Abundance of benthic foraminifera in late Paleocene to eraly Pliocene sediments of DSDP Hole 74-525A on the Walvis Ridge, South Atlantic (Table 1)

Benthic forammifers in the size-fraction greater than 0.073 mm were studied in 88 Paleocene to Pleistocene samples from Deep Sea Drilling Project Site 525 (Hole 525A, Walvis Ridge, eastern south Atlantic). Clustering of the samples on the basis of the 86 most abundant foramimfers (in total, 331 taxa were identified) allowed separating two major assemblage zones: the Paleocene to Eocene interval, and the Oligocene to Pleistocene interval. Each of these, in turn, were subdivided into three minor subzones as follows: lower upper Paleocene (approx. 62.4 to 57 8 Ma); upper upper Paleocene (56.6 to 56 2 Ma), lower and middle Eocene (55.3 to 46 8 Ma); upper Oligocene to middle Miocene (25.3 to 16 Ma), middle Miocene to Pliocene (15.7 to 4.2 Ma), and lower Pleistocene (0.4 to 0.02 Ma), with only minor differences with the previous zone. Some very abundant taxa span most of the column studies (Bolivina huneri, Cassidulina subglobosa, Eponides bradyi, E. weddellensis, Gavelinella micra, Oridorsalis umbonatus, etc.). Several of the faunal breaks recorded coincide with conspicuous minima in the specific diversity curve, thus suggesting that the corresponding turnovers signal the final stages of periods of faunal impoverishment. At least one major bottomwater temperature drop (as derived from delta18O data) is synchronous with a decrease in the forammiferal specific diversity. On the other hand, a specific diversity maximum in the middle Miocene might be associated with a delta13C increase at approx 16 to 12 Ma. Highest foraminiferal abundances (up to 600-800 individuals per gram of dry sediment) occurred in the late Paleocene and in the early Pleistocene, in coincidence with the lowest diversity figures calculated. The magnitude of the most important faunal turnover recorded, between the middle Eocene and the late Oligocene, is magnified in our data set by the large hiatus which separates the middle Eocene from the upper Oligocene sediments. Considerably smaller overturns occurred within the late Paleocene (in coincidence with changes in the specific diversity, absolute abundance of forammiferal tests, and delta13C), and in the middle Miocene (in coincidence with a specific diversity maximum and a delta13C excursion). New reformation on the morphology and the stratigraphic ranges of several species is furnished. For all the taxa recorded the number of occurrences, total number of individuals identified and first and last appearances are listed.

(Table 1) Heat flow data in the western Black Sea

Results of heat flow measurements are presented. On the basis of new data on structure of the sedimentary sequence, corrections are introduced that take account of effect of sedimentation. Diagrammatic maps of distribution of observed and deep-seated heat flow have been constructed. A hypothesis is offered that the regional zone of anomalously high heat-flow values on the northern continental slope has been controlled by processes of subsidence of an oceanic plate beneath its continental counterpart.

(Table 1) Lead, thorium and uranium isotopic concentration and ages of zircons from Yenisey Ridge metapelites

Reconstruction of the geologic history of the Yenisey Ridge, which developed as an accretionary collision orogen on the western margin of the Siberian craton is essential to understanding the evolution of mobile belts surrounding older cratons, as well as to resolving the recently much debated problem of whether Siberia was part of the supercontinent Rodinia. Available paleotectonic models suggest that this supercontinent was assembled at the Middle-Late Riphean boundary (1100-900 Ma) as a result of the Grenville orogeny, the first long-lived mountain building event which occurred in geosynclinal areas during the Neogaea. However, the character of crustal evolution at that stage is still speculative due to the lack of reliable and conclusive isotope data. In many current geodynamic models, a common underlying assumption is that the Yenisey Ridge showed very little endogenic activity for 1 Gyr, from the time of Tarak granite emplacement (1900-1840 Ma) to the Middle Neoproterozoic (~750 Ma). On the basis of this assumption, several recent studies suggested the absence of Grenvillian collisional events within the Yenisey Ridge. The results of the SHRIMP II U-Pb analysis of rift-related plagiogranites of the Nemtikha Complex, Yenisey Ridge (1380-1360 Ma) suggest an increase in magmatic activity in the Mesoproterozoic. Interpretation of these results in terms of a supercontinent cycle may help find evidence for possible occurrence of the Grenville orogeny on the western margin of the Siberian craton. With this in mind, we attempted to reconstruct using recent geochronological constraints the evolution of metapelitic rocks from the Teya polymetamorphic complex (TPMC), which is a good example of superimposed zoning of low and medium-pressure facies series. High precision age determinations from rock complexes formed in different geodynamic settings under different thermodynamic conditions and geothermal gradients were used to distinguish several major metamorphic events and unravel their time relations with tectonic and magmatic activity in the region.