Investigation of manganese nodules from the Southern Tasman Sea

Two manganese nodules having a high clay content, a low Mn/Fe ratio, and low contents of valuable metals (Ni 0.25%, Cu 0.17%, Co 0.06%) were recovered in a grab sample during a short geological cruise in HMAS Kimbla in the southern Tasman Sea in May 1979. Five stations were occupied. Free-fall grabs recovered sediment or pumice from four stations; nothing was recovered from the fifth. The carbonate compensation depth in the region is about 4500 m. Reddish brown clay, but no manganese nodules, was recovered in the central southern Tasman Sea, from depths of 4900-5100 m. The nodules, together with grey calcareous mud, were obtained from a depth of 4300 m, farther to the northwest, near Gascoyne Seamount (250 n. miles SE of Sydney). The results suggest nodules with high metal values are likely to exist only in the broad and deep depression in the central southern Tasman Sea southeast of Gascoyne Seamount, where sedimentation rates are low and oxidising conditions prevail. Whether nodule fields are present or not will only be resolved by considerably more sampling.

Stable isotope record of benthic and planktonic foraminifera in sediment cores of ODP Leg 177, Southern Ocean

While onboard ship during Leg 177, we used variations in sediment physical properties (mainly percent color reflectance) in conjunction with biomagnetostratigraphy to correlate among sites and predict the position of marine isotope stages (MISs) (e.g., see fig. F11 in Shipboard Scientific Party, 1999, p. 45). Our working assumption was that physical properties of Leg 177 sediments are controlled mainly by variations in carbonate content. Previous studies of Southern Ocean sediment cores have shown that carbonate concentrations are relatively high during interglacial stages and low during glacial stages at sites located within the Polar Frontal Zone (PFZ). Today, the PFZ marks a lithologic boundary in underlying sediment separating calcareous oozes to the north and silica-rich facies to the south (Hays et al., 1976). Although there is debate whether the position of the "physical" PFZ actually moved during glacial-interglacial cycles (Charles and Fairbanks, 1990; Matsumoto et al., 2001), the "biochemical" PFZ, as expressed by the CaCO3/opal boundary in sediments, certainly migrated north during glacials and south during interglacials. This gave rise to lithologic variations that are useful for stratigraphic correlation. At Leg 177 sites located north of the PFZ and at sublysoclinal depths, we expected the same pattern of carbonate variation because cores in the Atlantic basin are marked by increased carbonate dissolution during glacial periods and increased preservation during interglacials (Crowley, 1985).

Abundance and biomass of mesozooplankton in the Levantine Basin during the Bilim 2 cruise in April 2008

The Sesame dataset contains mesozooplankton data collected during April 2008 in the Levantine Basin (between 33.20 and 36.50 N latitude and between 30.99 and 31.008 E longitude). Mesozooplankton samples were collected by using a WP-2 closing net with 200 µm mesh size during day hours (07:00-18:00). Samples were taken from 0-50, 50-100, 100-200 m layers at 5 stations in Levantine Basin The dataset includes samples analyzed for mesozooplankton species composition, abundance and total mesozooplankton biomass. Sampling volume was estimated by multiplying the mouth area with the wire length. Sampling biomass was measured by weighing filters and then determined by sampling volume. The samples were sieved sequentially through meshes of 500 and 200 micron to separate the mesozooplankton into size fractions. The entire sample (1/2) or an aliquot of the taxon-specific mesozooplankton abundance and the total abundance of the mesozooplankton were was analyzed under the binocular microscope. Minimum 500 individuals of mesozooplankton were identified and numerated at higher taxonomic level. Taxonomic identification was done at the METU- Institute of Marine Sciences by Alexandra Gubanova,Tuba Terbiyik using the relevant taxonomic literatures. Mesozooplankton abundance and biomass were estimated by Zahit Uysal and Yesim Ak.

Abundance of mesozooplankton in the Levantine Basin during the Bilim 2 cruise in October 2008

The Sesame dataset contains mesozooplankton data collected during October 2008 in the Levantine Basin (between 33.20 and 36.50 N latitude and between 30.99 and 31.008 E longitude). Mesozooplankton samples were collected by using a WP-2 closing net with 200 µm mesh size during day hours (07:00-18:00). Samples were taken from 0-50, 50-100, 100-200 m layer at 5 stations in Levantine Basin The dataset includes samples analyzed for mesozooplankton species composition, abundance and total mesozooplankton biomass. The entire sample (1/2) or an aliquot was analyzed under the binocular microscope. Minimum 500 individuals of mesozooplankton were identified and numerated at higher taxonomic level. Taxonomic identification was done at the METU- Institute of Marine Sciences by Alexandra Gubanova,Tuba Terbiyik using the relevant taxonomic literatures. Mesozooplankton abundance and biomass were estimated by Zahit Uysal and Yesim Ak Örek. Specification via marine planktonic copepods database (http://copepodes.obs-banyuls.fr/en/).

Abundance of mesozooplankton in the Cilician Basin during the Bilim 2 cruise in March 2008

The Sesame dataset contains mesozooplankton data collected during March 2008 in the Cilician Basin (between between 35.40'- 36.79 N latitude and 33.19- 36.07 E ). Mesozooplankton samples were collected by using a WP-2 closing net with 200 micron mesh size during day hours (07:00-18:00). Samples were taken in the 0-50, 50-100, 100-200 m layer at 6 stations in the Cilician Basin. The dataset includes samples analyzed for mesozooplankton species composition, abundance and total biomass (Dry weight(mg/m**3)). Taxon-specific mesozooplankton abundance: 1/2 sample or an aliquot was analyzed under the binocular microscope. Copepod species were identified and enumerated; the other mesozooplankters were identified and enumerated at higher taxonomic level (commonly named as mesozooplankton groups). Taxonomic identification was done at the METU-Institute of Marine Sciences by Tuba Terbiyik using the relevant taxonomic literatures. Mesozooplankton total abundance: 1/2 sample or an aliquot was analyzed under the binocular microscope. Copepod species were identified and enumerated; the other mesozooplankters were identified and enumerated at higher taxonomic level (commonly named as mesozooplankton groups). Taxonomic identification was done at the METU-Institute of Marine Sciences using the relevant taxonomic literatures

Composition of Fe-Mn nodules and crusts from the Cape Basin

Facies zonation of the Cape basin with respect to Fe-Mn nodules based on data from Cruise 43 of R/V Akademik Kurchatov and published data is presented. Three facies regions are distinguished: the southern end of the Walvis Ridge and seamounts, the continental slope of the Southwest Africa and the deep-water Cape Basin. Iron-manganese nodules in the first of these areas are predominantly sedimentary, those in the second area are diagenetic and those in the third are sedimentary-diagenetic. Chemical characteristics and type of metallogenic specialization for each of the regions are identified.

Early Oligocene continental climate ofthe Paleogene Basin in Hungary and Slovenia

This paper concentrates on the Early Oligocene palaeoclimate of the southern part of Eastern and Central Europe and gives a detailed climatological analysis, combined with leaf-morphological studies and modelling of the palaeoatmospheric CO2 level using stomatal and d13 C data. Climate data are calculated using the Coexistence Approach for Kiscellian floras of the Palaeogene Basin (Hungary and Slovenia) and coeval assemblages from Central and Southeastern Europe. Potential microclimatic or habitat variations are considered using morphometric analysis of fossil leaves from Hungarian, Slovenian and Italian floras. Reconstruction of CO2 is performed by applying a recently introduced mechanistic model. Results of climate analysis indicate distinct latitudinal and longitudinal climate patterns for various variables which agree well with reconstructed palaeogeography and vegetation. Calculated climate variables in general suggest a warm and frost-free climate with low seasonal variation of temperature. A difference in temperature parameters is recorded between localities from Central and Southeastern Europe, manifested mainly in the mean temperature of the coldest month. Results of morphometric analysis suggest microclimatic or habitat difference among studied floras. Extending the scarce information available on atmospheric CO2 levels during the Oligocene, we provide data for a well-defined time-interval. Reconstructed atmospheric CO2 levels agree well with threshold values for Antarctic ice sheet growth suggested by recent modelling studies. The successful application of the mechanistic model for the reconstruction of atmospheric CO2 levels raises new possibitities for future climate inference from macro-flora studies.

Geochemistry of surface and groundwaters from lower Tom Basin wetland, western Siberia

New data are reported on the major- and trace-component compositions of acidic and weakly acidic low-concentration wetland waters and other water types. Special attention was given to dissolved organic compounds: fulvic and humic acids, bitumens, and hydrocarbons. The first comprehensive data are presented for organic trace components in the wetland waters of western Siberia: alkanes, pentacyclic terpenoids, steranes, alkylbenzenes, naphthalenes, phenanthrenes, tetraarenes, etc.