(Table 1) Positions of the Mesocena elliptica zone in sediment cores from the Pacific and Indian Oceans

The Mesocena elliptica Ehr. zone in deep-sea sediments of the Pacific Ocean is characterized by a short vertical range at the base of the Pleistocene section. Depending on sedimentation rate this zone lies at various depths below the ocean bottom. M. elliptica is unknown in recent oceanic plankton. In fossil state known species indicate that sediments containing them are of Oligocene-Miocene age. New data obtained in early 1960's show that within a short interval, evidently in Early Pleistocene, M. elliptica was abundant in plankton, primarily in tropical regions. Correlation of paleomagnetic data with results of diatom analysis shows that the Mesocena elliptica zone always lies above the Pliocene-Pleistocene boundary, and that maximum contents of M. elliptica coincide with the Jaramillo event (0.85-0.95 million years ago).

Oligocene to middle Miocene radiolarians of Maud Rise, Weddell Sea

At Sites 689 and 690, drilled during ODP (Ocean Drilling Program) Leg 113 on the Maud Rise (southeast Weddell Sea), moderately to well preserved radiolarian assemblages were obtained from continuously recovered upper Oligocene and Neogene sequences. Based on radiolarian investigations, a biostratigraphic zonation for a time interval covering the late Oligocene to the middle Miocene is proposed. The radiolarian zonation comprises 10 zones. Five zones are new, and five zones previously defined by Chen (1975) were modified. The zones and the ranges of the nominate species are directly calibrated with a geomagnetic polarity record. This is the first attempt at a direct correlation of late Oligocene to middle Miocene radiolarian zones with the geomagnetic time scale. Six hiatuses were delineated in the studied upper Oligocene to middle Miocene sections. One major hiatus, spanning ca. 6 m.y., is between the upper Oligocene and the lower Miocene sequences. Another important hiatus separates the lower and middle Miocene sediments. As a base for the biostratigraphic investigations, a detailed taxonomic study of the recovered radiolarian taxa is achieved. Three new radiolarian species that occur in upper Oligocene and lower Miocene sediments are described (Cycladophora antiqua, Cyrtocapsella robusta, and Velicucullus altus).

Os isotope record of ODP Site 159-959

The known temporal relationship between the benthic foraminiferal d18O record and the marine Os isotope record is used to reinterpret the absolute chronology and paleoceanographic context of an episode of organic carbon burial on the West African margin Ocean Drilling Program (ODP) Site 959. Although organic-rich sediments require significant corrections for in situ decay of 187Re to 187Os, these results demonstrate the utility of the marine Os isotope record for chemostratigraphic correlation of organic-rich sediments that are devoid of age diagnostic microfossils with pelagic carbonate sequences. Revision of the ODP Site 959 chronology shifts the age assignment of an interval of biosiliceous, organic-rich sediment deposition from the Oligocene to the late Eocene and earliest Oligocene, likely culminating with the first major glaciation of the Oligocene (Oi1). We speculate that enhanced organic carbon burial over much of the West African margin may have contributed to drawdown of atmospheric carbon dioxide before and during the Oi1 event and suggest that Os isotope chemostratigraphy provides a valuable tool for further exploring this possibility.

Mineralogical, sedimentological and paleontological analyses of ODP Hole 127-797B upper Quarternary sediments

Nearly continuous cores of Quaternary fine-grained sediments with distinct dark-light colored cycles were recovered from Sites 794, 795, and 797 in the basinal parts of the Japan Sea during Leg 127. A comparison of gray value (darkness) profiles supplemented by visual inspection of core photographs between sites indicated that most of the dark and light layers were correlatable between sites, and that two of the dark layers lie close to adjacent marker ash layers. These observations indicate that deposition of dark and light layers resulted from basin-wide synchronous events. In order to understand the origin of these dark-light cycles, petrographical, mineralogical, compositional, and paleontological studies were carried out on closely spaced samples from the upper Quaternary sediments recovered from Site 797. Age model was constructed based on comparison between variation in diatom abundance and the standard oxygen isotope curve of Imbrie et al. (1984), the latter was interpolated between the five age controlled levels established at Site 797. The two curves show similar patterns which enabled us to "tune" the sediment ages to the oxygen isotope stages. We have to use variation in diatom abundance as a substitute for oxygen isotope curve since oxygen isotopic data are not available at the studied sites. Bottom water oxygenation conditions were estimated based on two criteria: (1) the degree of lamina preservation and (2) the ratio of Corg to Stot. The surface water productivity was deduced from the Corg and biogenic silica content. Results suggest that the bottom water oxygenation level and the surface water productivity varied significantly in response to the glacial-interglacial cycles. Glacio-eustatic sea-level changes and subsequent changes in water circulation in the Japan Sea appear to have been responsible for these variations and consequent changes in sediment composition throughout the Quaternary.

Tab. 1: U-Pb analyses of zircons from rock samples in MT. Newton and Cumpston Massif, East Antarctica

We present new U-Pb zircon (SHRIMP) data on rocks from Mt Newton and Cumpston Massif in the southern Prince Charles Mountains. Our data demonstrate that Mt Newton was affected by a newly proposed Palaeoproterozoic "Newton" Orogeny at c. 2100-2200 Ma. Sedimentation, felsic volcanism (c. 2200 Ma), metamorphism and folding, followed by granite intrusion (c. 2100 Ma), suggest development of a trough or aulacogene in the area during the early Palaeoproterozoic. An orthogneiss from Cumpston Massif yielded an age of c. 3180 Ma for granitic protolith emplacement, which is in good agreement with many U-Pb zircon ages from similar rocks in the southern Mawson Escarpment. A syn- to late-tectonic muscovite-bearing pegmatite from Cumpston Massif yielded a c. 2500 Ma date of emplacement, which indicates early Palaeoproterozoic activity in this block, probably in response to a tectono-magmatic episode in the Lambert Terrane bordering the Ruker Terrane in the northeast. The correlation of tectono-magmatic events in both the Ruker and Lambert terranes of the southern Prince Charles Mountains provides evidence for their common evolution during the Proterozoic.

Age models of northern North Atlantic sediment cores

Benthic foraminiferal stable isotope records from four high-resolution sediment cores, forming a depth transect between 1237 m and 2303 m on the South Iceland Rise, have been used to reconstruct intermediate and deep water paleoceanographic changes in the northern North Atlantic during the last 21 ka (spanning Termination I and the Holocene). Typically, a sampling resolution of ~100 years is attained. Deglacial core chronologies are accurately tied to North Greenland Ice Core Project (NGRIP) ice core records through the correlation of tephra layers and changes in the percent abundance of Neogloboquadrina pachyderma (sinistral) with transitions in NGRIP. The evolution from the glacial mode of circulation to the present regime is punctuated by two periods with low benthic d13C and d18O values, which do not lie on glacial or Holocene water mass mixing lines. These periods correlate with the late Younger Dryas/Early Holocene (11.5-12.2 ka) and Heinrich Stadial 1 (14.7-16.8 ka) during which time freshwater input and sea-ice formation led to brine rejection both locally and as an overflow exported from the Nordic seas into the northern North Atlantic, as earlier reported by Meland et al. (2008). The export of brine with low ?13C values from the Nordic seas complicates traditional interpretations of low d13C values during the deglaciation as incursions of southern sourced water, although the spatial extent of this brine is uncertain. The records also reveal that the onset of the Younger Dryas was accompanied by an abrupt and transient (~200-300 year duration) decrease in the ventilation of the northern North Atlantic. During the Holocene, Iceland-Scotland Overflow Water only reached its modern flow strength and/or depth over the South Iceland Rise by 7-8 ka, in parallel with surface ocean reorganizations and a cessation in deglacial meltwater input to the North Atlantic.

Geochemistry of bulk sediment from the Cape Basin

A technique for onsite application of X-ray fluorescence (XRF) spectrometry to samples from sediment cores aboard a research vessel was developed and tested. The method is sufficiently simple, precise, and fast to be used routinely for high-resolution analyses of depth profiles as well as surface samples. Analyses were performed with the compact high-performance energy-dispersive polarisation X-ray fluorescence (EDPXRF) analyser Spectro Xepos. Contents of the elements Si, Ti, Al, Fe, Mn, Mg, Ca, K, Sr, Ba, Rb, Cu, Ni, Zn, P, S, Cl and Br were simultaneously determined on 200-225 samples of each core within 24 h of recovery. This study presents a description of the employed shipboard preparation and analysis technique, along with some example data. We show land-based datasets that support our decisions to use powder samples and to reduce the original measuring time for onboard analyses. We demonstrate how well the results from shipboard measurements for the various elements compare with the land-based findings. The onboard geochemical data enabled us to establish an element stratigraphy already during the cruise. Correlation of iron, calcium and silicon enrichment trends with an older reference core provided an age model for the newly retrieved cores. The Spectro Xepos instrument performed without any analytical and technical difficulties which could have been caused by rougher weather conditions or continuous movement and vibration of the research vessel. By now, this XRF technique has been applied during three RV Meteor cruises to approximately 5,000 Late Quaternary sediment samples from altogether 23 gravity cores, 25 multicorer cores and two box cores from the eastern South Atlantic off South Africa/Namibia and the eastern Atlantic off NW Africa.

(Table 1) Water storage changes of the 33 world's largest river basins between 2002-2009

Global change in land water storage and its effect on sea level is estimated over a 7-year time span (August 2002 to July 2009) using space gravimetry data from GRACE. The 33 World largest river basins are considered. We focus on the year-to-year variability and construct a total land water storage time series that we further express in equivalent sea level time series. The short-term trend in total water storage adjusted over this 7-year time span is positive and amounts to 80.6 ± 15.7 km**3/yr (net water storage excess). Most of the positive contribution arises from the Amazon and Siberian basins (Lena and Yenisei), followed by the Zambezi, Orinoco and Ob basins. The largest negative contributions (water deficit) come from the Mississippi, Ganges, Brahmaputra, Aral, Euphrates, Indus and Parana. Expressed in terms of equivalent sea level, total water volume change over 2002-2009 leads to a small negative contribution to sea level of -0.22 ± 0.05 mm/yr. The time series for each basin clearly show that year-to-year variability dominates so that the value estimated in this study cannot be considered as representative of a long-term trend. We also compare the interannual variability of total land water storage (removing the mean trend over the studied time span) with interannual variability in sea level (corrected for thermal expansion). A correlation of ~0.6 is found. Phasing, in particular, is correct. Thus, at least part of the interannual variability of the global mean sea level can be attributed to land water storage fluctuations.

Contents of major components, U, and Th in bones and bone debris

Uranium and thorium contents, as well as their distribution patterns have been studied in biogenic phosphates from the Atlantic and Pacific Oceans. Differently lithified fish remains (bones, scales, teeth) and marine mammal bones (ribs, vertebras, earbones) collected from both reduced shelf sediments and oxidized pelagic ones have been analyzed. U content in the material varies from 0.7 to 700 ppm, and Th content - from <0.5 to 14 ppm. U/Th ratio varies from 0.16 to 400. Contents of both elements increase with lithification of biogenic phosphates. U concentration is more intense on shelves, whereas thorium concentration increases in pelagic areas. Partial positive correlation of U and Th with Fe and negative correlation of U with organic carbon are noted. The latter corresponds to higher lithification of biogenic phosphates. Calcium phosphate transformed from hydroxyapatite to fluorcarbonate-apatite is the main carrier of U, while transformed organic matter is a minor agent. Thorium is mainly bound with Fe.

Stable carbon and oxygen isotope compositions of bulk rock samples analyzed from the Zumaia section

Astronomical tuning of sedimentary records to precise orbital solutions has led to unprecedented resolution in the geological time scale. However, the construction of a consistent astronomical time scale for the Paleocene is controversial due to uncertainties in the recognition of the exact number of 405-kyr eccentricity cycles and accurate correlation between key records. Here, we present a new Danian integrated stratigraphic framework using the land-based Zumaia and Sopelana hemipelagic sections from the Basque Basin and deep-sea records drilled during Ocean Drilling Program (ODP) Legs 198 (Shatsky Rise, North Pacific) and 208 (Walvis Ridge, South Atlantic) that solves previous discrepancies. The new coherent stratigraphy utilises composite images from ODP cores, a new whole-rock d13C isotope record at Zumaia and new magnetostratigraphic data from Sopelana. We consistently observe 11 405-kyr eccentricity cycles in all studied Danian successions. We achieve a robust correlation of bioevents and stable isotope events between all studied sections at the ~100-kyr short-eccentricity level, a prerequisite for paleoclimatic interpretations. Comparison with and subsequent tuning of the records to the latest orbital solution La2011 provides astronomically calibrated ages of 66.022 ± 0.040 Ma and 61.607 ± 0.040 Ma for the Cretaceous-Paleogene (K-Pg) and Danian-Selandian 105 (D-S) boundaries respectively. Low sedimentation rates appear common in all records in the mid-Danian interval, including conspicuous condensed intervals in the oceanic records that in the past have hampered the proper identification of cycles. The comprehensive interbasinal approach applied here reveals pitfalls in time scale construction, filtering techniques in particular, and indicates that some caution and scrutiny has to be applied when building orbital chronologies. Finally, the Zumaia section, already hosting the Selandian Global Boundary Stratotype Section and Point (GSSP), could serve as the global Danian unit stratotype in the future.

Susceptibility, density, iron and calcium concentrations of ODP holes 165-999B and 165-1001A

Pelagic sediments recording an extreme and short-lived global warming event, the Late Paleocene Thermal Maximum (LPTM), were recovered from Hole 999B (Colombian Basin) and Holes 1001A and 1001B (lower Nicaraguan Rise) in the Caribbean Sea during Ocean Drilling Program Leg 165. The LPTM consists of a 0.3-0.97 m calcareous claystone to claystone horizon. High-resolution downhole logging (Formation MicroScanner [FMS]), standard downhole logs (resistivity, velocity, density, natural gamma ray, and geochemical log), and non-destructive chemical and physical property (multisensor core logger [MSCL] and X-ray fluorescence [XRF] core scanner) data were used to identify composite sections from parallel holes and to record sedimentological and environmental changes associated with the LPTM. Downhole logging data indicate an abrupt and distinct difference in physical and chemical properties that extend for tens of meters above and below the LPTM. These observations indicate a rapid environmental change at the LPTM, which persists beyond the LPTM anomaly. Comparisons of gamma-ray attenuation porosity evaluator (GRAPE) densities from MSCL logging on split cores with FMS resistivity values allows core-to-log correlation with a high degree of accuracy. High-resolution magnetic susceptibility measurements of the cores are compared with elemental concentrations (e.g., Fe, Ca) analyzed by high-resolution XRF scanning. The high-resolution data obtained from several detailed core and downhole logging methods are the key to the construction of composite sections, the correlation of both adjacent holes and distant sites, and core-log integration. These continuous-depth series reveal the LPTM as a multiphase event with a nearly instantaneous onset, followed by a much different set of physical and chemical conditions of short duration, succeeded by a longer transition to a new, more permanent set of environmental circumstances. The estimated duration of these 'phases' are consistent with paleontological and isotopic studies of the LPTM

Grain shape of sediment from the Weddell Sea

Very fine quartz sand was examined from Paleogene and Neogene sediments of ODP Sites 693, 694, 695, 696, and 697 to determine their grain roundness using Fourier analysis and SEM surface texture characteristics. The objective of this study was to identify grain roundness and surface texture characteristics unique to East (Site 693) and West (Sites 695, 696, and 697) Antarctica and to glacial regimes. Once identified, these distinguishing features could then be used to determine changes in source area and glacial conditions in the central Weddell Sea Basin (Site 694). Three end members of very fine quartz sand are recognized in the Oligocene to Pleistocene sediments of the Weddell Sea: angular, rounded, and intermediate. End member 1 (angular) consists of extremely angular grains with numerous fracture textures. Previous investigations suggested that these sands are derived from crystalline rocks that fractured during formation or deformation and/or were exposed to weathering by ice. In this study, however, the correlation of angularity with ice activity is problematical as the most angular sands were recovered in the lower Oligocene sediments of the South Orkney Microcontinent, a period of temperate climatic conditions. End member 3 (rounded) consists of rounded grains with chemically and mechanically produced surface textures. These sands are presumed to be derived from the Beacon-type rocks in East Antarctica and the sedimentary deposits of the Northern Antarctic Peninsula. End member 2 (intermediate) grains display crystalline nodes and grain embayments. They are thought to be derived from felsic intrusives, East Antarctic quartzites, basement metamorphics of the South Orkney Microcontinent, and/or the Andean intrusive series of West Antarctica. Unfortunately, no features unique to either the East or West Antarctic sediment sources or to glacial conditions could be isolated. Therefore, the objective of determining provenance changes and sediment erosion and transport mechanisms could not be achieved using this approach.

Fluorescence of dissolved organic matter un marine sediments

The fluorescence of porewaters from marine sediment cores from six different areas was measured. In most cases, fluorescence was affected primarily by the diagenesis of organic carbon first through sulfate reduction and subsequently by methane generation. Typically, fluorescence, dissolved organic carbon (DOC), absorbance, alkalinity, and ammonium ion concentrations correlate quite well, increasing in the upper sections of anoxic sediments and co-varying in deeper sections of these cores. The good correlation of DOC with fluorescence in the three cores in which DOC was measured indicates that fluorescence can be used to make a first order estimate of DOC concentration in anoxic porewaters. Data are consistent with a model in which labile organic matter in the sediments is broken down by sulfur reducing bacteria to low molecular weight monomers. These monomers are either remineralized to CO2 or polymerize to form dissolved, fluorescent, high molecular weight molecules. The few exceptions to this model involve hydrothermally generated hydrocarbons that are formed in situ in the Guaymas Basin or are horizontally advected along the decollement in the Nankai Trench.

Mineralogy and geochemistry of altered ash, pelagic clay, and a clay vein in basalt from DSDP Leg 62 Holes

Volcanic ash was recovered from lower Aptian to Albian deposits from DSDP Sites 463, 465, and 466; pelagic clay of the upper Pleistocene to Upper Cretaceous was recovered mainly from Site 464, with minor amounts at Sites 465 and 466. We present X-ray-mineralogy data on pelagic clay and altered volcanic ash recovered from the four Leg 62 sites. In addition, two ash samples from Sites 463 and 465, a pelagic clay from Site 464, and a clay vein from the basaltic basement at Site 464 each were analyzed for major, minor, and trace elements. Our purpose is to describe the mineralogy and chemistry of altered ash and pelagic clays, to determine the sources of their parent material, and to delineate the diagenetic history of these clay-rich deposits. Correlation of chemistry and mineralogy of ash and pelagic clay with volcanic rocks suspected to be their parent material is not always straightforward, because weathering and diagenetic alteration caused depletion or enrichment of many elements.

Maestrichtian planktonic foraminifera of the Maud Rise

The southernmost record of Maestrichtian pelagic carbonate sedimentation was recovered from ODP Leg 113 Holes 689B and 690C, drilled on the Maud Rise in the eastern Weddell Sea sector of the Southern Ocean (65°S). Well preserved and abundant planktonic foraminifers occur throughout Maestrichtian cores from both holes, providing a nearly complete biogeographic and biostratigraphic history of this region. Diversity is low compared to tropical and subtropical assemblages, with a maximum within sample diversity of 16 planktonic foraminifer species and a diversity total for the Maestrichtian of 24 species. The assemblages are dominated throughout by Heterohelix, Globigerinelloides, and a new species of Archaeoglobigerina, whereas keeled taxa are completely absent from the lower Maestrichtian and rare in the middle through upper Maestrichtian sediments. Three planktonic foraminifer species are described as new and are recognized as being endemic to the Austral Province. These include Archaeoglobigerina australis n. sp., Hedbergella sliteri n. sp., and Archaeoglobigerina mateola n. sp. The former two species were previously illustrated in reports on Late Cretaceous foraminifers from the Falkland Plateau and the northern Antarctic Peninsula. Two keeled and five non-keeled planktonic foraminifers, previously not found in high latitude Maestrichtian sediments, first appeared at the Maud Rise during the late early and late Maestrichtian. Correlation with their stratigraphic ranges in low latitude sequences shows that their first appearance datums are considerably younger at the Maud Rise than in the lower latitudes. The most likely explanation for this observation is that there was a warming in the south polar region during the late early and late Maestrichtian and a concomitant poleward migration of stenothermal taxa. However, oxygen isotopic paleotemperature results from Sites 689 and 690 (Barrera and Huber, 1990, doi:10.2973/odp.proc.sr.113.137.1990) show a long-term cooling trend throughout the Maestrichtian, indicating that other factors may have played a more important role than temperature in the distribution of Maestrichtian planktonic foraminifers. A new biostratigraphic scheme is proposed for the Antarctic because of the absence of thermophilic planktonic foraminifers used to identify existing low to middle latitude zones. The Globigerinelloides impensus Partial Range Zone is defined for the late Campanian-Maestrichtian, the Globotruncanita havanensis Partial Range Zone is redefined for the early to late early Maestrichtian, and the Abathomphalus mayaroensis Total Range Zone is recognized. Good quality magnetic polarity data obtained from both Maud Rise sites (Hamilton, 1990, doi:10.2973/odp.proc.sr.113.179.1990) enables magnetobiostratigraphic correlation of twelve foraminifer datums with the geomagnetic polarity time scale of Haq et al. (1987). The geochronology thus obtained is crucial for accurate cross-latitudinal correlation and interpretation of the paleoceanographic history of the Antarctic region during the Maestrichtian time period.