(Table 1) Summary of accelerator mass spectrometer (AMS) radiocarbon ages in ODP Sites 169-1033 and 169-1034

Continuous coring in Saanich Inlet (Ocean Drilling Program, ODP Leg 169S), British Columbia, Canada, yielded a detailed record of Late Quaternary climate, oceanography, marine productivity, and terrestrial vegetation. Two sites (1033 and 1034) were drilled to maximum depths of 105 and 118 m, recovering sediments ranging in age from 13,300 to less than 300 14C yr. Earliest sediments consist of dense, largely massive, gray glaciomarine muds with dropstones and sand and silt laminae deposited during the waning stages of glaciation. Deposition of organic-rich olive gray sediments began in the fjord about 12,000 14C yr ago, under well-oxygenated conditions as reflected by the presence of bioturbation and a diverse infaunal bivalve community. At about 10,500 14C yr, a massive, gray unit, 40-50 cm thick, was emplaced in a very short span of time. The unit is marked by a sharp lower contact, a gradational upper contact and an abundance of reworked Tertiary microfossils. It has been interpreted as resulting from massive flood events caused by the collapse of glacial dams in the Fraser Valley of mainland British Columbia. Progressively greater anoxia in bottom waters of Saanich Inlet began about 7000 14C yr ago. This is reflected in the preservation of varved sediments consisting of diatomaceous spring-summer laminae and terrigenous winter laminae. Correlation of the sediments was based on: marked lithologic changes, the presence of massive intervals (reflecting localized sediment gravity flow events), the Mazama Ash, occasional thin gray laminae (indicative of abnormal flood events in nearby watersheds), varve counts between marker horizons, and 71 accelerator mass spectrometry (AMS) radiocarbon dates.

Appendix A: LA-ICP-MS results (Laser-ablation inductively coupled plasma mass spectrometer) from monazite Moacir standard

Three samples of garnet-kyanite paragneiss from the Variscan Ulten Zone (Northern Italy) were studied in detail for U-Th-Pb monazite dating. Monazite in these gneisses is abundant, shows highly variable grain size and occupies different textural positions: within the matrix, as inclusion in garnet and kyanite, within apatite aggregates. Monazite shows different deformation features as a function of the textural position: enclosed (shielded) monazite is generally more fractured than matrix (unshielded) monazite. The integration of textural information with deformation features and in situ U-Th-Pb analyses by LA-ICP-MS indicates that there is no direct correlation between textural site and monazite ages. Old ages of 351-343 Ma, determined on portions of large matrix (unshielded) monazite and on rare domains of monazite shielded by garnet, have been related to a prograde stage of the Variscan metamorphic evolution of the Ulten Zone. Ages of 330-326 Ma, which are related to the thermal peak, are recorded by small matrix monazite, external domains of large matrix monazite, and by (domains of) fractured monazite enclosed in garnet and kyanite. Large, old unshielded grains formed as blasts during the prograde metamorphic history and survived the peak metamorphism during which crystallisation/re-crystallisation partially occurred.

Alkenones in surface waters of the Nordic seas

Samples of filtered particulate organic matter (POM) were obtained during the summers of 1999 and 2000 from the surface waters of the Nordic seas to monitor the spatial distribution of long-chain alkenones. The aim of the study was to appraise existing alkenone-based climatic proxies in northern high latitudes. Unusually high percentages of the tetraunsaturated alkenone were measured in the polar waters of the East Greenland Current, with C37:4 of up to 77% in 80% of sea-ice cover. Values of percent C37:4 across the Nordic seas showed a strong association with water mass type. Analysis of coccoliths in filters indicated that calcified Emiliania huxleyi could not be discounted as the biological precursor of alkenones in all the water masses. A combined data set of 69 samples of POM revealed a stronger correlation of percent C37:4 to sea surface salinity (SSS; R2 = 0.72) than to sea surface temperature (SST; R2 = 0.50). Values of percent C37:4 in sea surface POM were much higher than those in surficial sediments of the northern North Atlantic. To explain the discrepancy in sedimentary and surface water column percent C37:4, we propose that the alkenone contents in surface sediments underlying arctic and polar waters are a combination of autochthonous and allochthonous inputs of alkenones. Our results show that percent C37:4 can be used to reconstruct the relative extension of arctic/polar water masses in the North Atlantic. However, the results prevent confirmation of percent C37:4 as a paleo-SSS proxy in the Nordic seas, given its multivariate nature in our data set and the decoupling between its range of values in surface waters and sediments.

O, C and Sr isotopic data for plankton and benthic foraminifera from DSDP Legs 26, 32, 36, and 71 sediments

A detailed d18O and d13C stratigraphy has been generated from analysis of well-preserved Albian - Early Maastrichtian foraminifera from Deep Sea Drilling Project (DSDP) Sites 511 and 327 (Falkland Plateau; ~58°S - 62°S paleolatitude) in the southern South Atlantic, and Cenomanian and Coniacian - Santonian foraminifera from DSDP Site 258 (Naturaliste Plateau; ~58°S paleolatitude) in the southern Indian Ocean. These results, when combined with previously published Maastrichtian stable isotope data from Ocean Drilling Program (ODP) Site 690 (Weddell Sea, ~65°S paleolatitude), provide new insight into the climatic and oceanographic history of the southern high latitudes during Middle-Late Cretaceous time. The planktonic foraminifer d18O curves reveal a gradual warming of surface waters from the Albian through the Cenomanian followed by extremely warm surface waters from the Turonian through the early Campanian. Long-term cooling of surface waters began in the late early Campanian and continued through the end of the Maastrichtian. The benthic foraminifer d18O record generally parallels changes in the oxygen isotopic curves defined by shallow-dwelling planktonic foraminifera. The vertical oxygen and carbon isotopic gradients were relatively low during the Albian - Cenomanian, high from the Turonian - Early Campanian, and then low during the late Campanian and Maastrichtian.

Non-isoprenoidal intact polar lipids, isoprenoidal and non-isoprenoidal core lipids, isoprenoidal intact polar lipids of the Black Sea site GeoB15105 sampled during Meteor cruise M84/1 in February 2011

This PhD thesis focused on the analysis and application of microbial membrane lipids as biomarkers in marine sediments. Existing protocols for lipid extraction from marine sediments and biomass were modified. In addition, recent protocols based on high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS) as well as state-of-the-art mass spectrometric analysis by quadrupole time-of-flight (MSqTOF) and the triple quadrupole (MSQQQ) mass spectrometer were used to investigate matrix effects and evaluate the reliability of quantitative analysis in marine environmental samples. The improved lipid extraction and quantification were used to analyze Black Sea water column and sediments samples to a depth of 8 meters from site GeoB 15105 taken during cruise M84/1 (DARCSEAS) with R/V Meteor to apply lipid analysis in benthic bio systems. With this component specific differentiation between planktonic and benthic lipid signature we assessed possible lipid sources. Here, this high detail lipid fingerprinting allowed us to observe changes in the head group and lipid core structures of the intact polar lipids according to the geochemical zonation.

Stable isotope record of benthic and planktonic foraminifera from ODP Site 175-1087 in the southern Cape Basin, Atlantic Ocean

High-resolution planktonic and benthic stable isotope records from Ocean Drilling Program Site 1087 off southeast Africa provide the basis for a detailed study of glacial-interglacial (G-IG) cycles during the last 500 k.y. This site is located in the Southern Cape Basin at the boundary of the coastal upwelling of Benguela and close to the gateway between the South Atlantic and the Indian Oceans. It therefore monitors variations of the hydrological fronts associated with the upwelling system and the Atlantic-Indian Ocean interconnections, in relation to global climate change. The coldest period of the last 500 k.y. corresponds to marine isotope Stage (MIS) 12, when surface water temperature was 4°C lower than during the last glacial maximum (LGM) as recorded by the surface-dwelling foraminifer Globigerinoides ruber. The warmest periods occurred during MISs 5 and 11, a situation slightly different to that observed at Site 704, which is close to the Polar Front Zone, where there is no significant difference between the interglacial stages for the past 450 k.y., except the long period of warmth during MIS 11. The planktonic and benthic carbon isotope records do not follow the G-IG cycles but show large oscillations related to major changes in the productivity regime. The largest positive 13C excursion between 260 and 425 ka coincides with the global mid-Brunhes event of carbonate productivity. The oxygen and carbon isotopic gradients between surface and deep waters display long-term changes superimposed on rapid and high-frequency fluctuations that do not follow the regular G-IG pattern; these gradients indicate modifications of the temperature, salinity, and productivity gradients due to changes in the thermocline depth, the position of the hydrological fronts, and the strength of the Benguela Current.

Measurements of trace metal abundances and isotopes in carbonate sediments, Exuma, Bahamas

In order to validate the use of 238U/235U as a paleoredox proxy in carbonates, we examined the incorporation and early diagenetic evolution of U isotopes in shallow Bahamian carbonate sediments. Our sample set consists of a variety of primary precipitates that represent a range of carbonate producing organisms and components that were important in the past (scleractinian corals, calcareous green and red algae, ooids, and mollusks). In addition, four short push cores were taken in different depositional environments to assess the impact of early diagenesis and pore water chemistry on the U isotopic composition of bulk carbonates. We find that U concentrations are much higher in bulk carbonate sediments (avg. 4.1 ppm) than in primary precipitates (avg. 1.5 ppm). In almost all cases, the lowest bulk sediment U concentrations were as high as or higher than the highest concentrations found in primary precipitates. This is consistent with authigenic accumulation of reduced U(IV) during early diagenesis. The extent of this process appears sensitive to pore water H2S, and thus indirectly to organic matter content. d238/235U values were very close to seawater values in all of the primary precipitates, suggesting that these carbonate components could be used to reconstruct changes in seawater U geochemistry. However, d238/235U of bulk sediments from the push cores was 0.2-0.4 per mil heavier than seawater (and primary precipitates). These results indicate that authigenic accumulation of U under open-system sulfidic pore water conditions commonly found in carbonate sediments strongly affects the bulk U concentrations and 238U/235U ratios. We also report the occurrence of dolomite in a tidal pond core which contains low 234U/238U and 238U/235U ratios and discuss the possibility that the dolomitization process may result in sediments depleted in 238U. From this initial exploration, it is clear that 238U/235U variations in ancient carbonate sediments could be driven by changes in global average seawater, by spatial and temporal variations in the local deposition environment, or subsequent diagenesis. To cope with such effects, proxies for syndepositional pore water redox conditions (e.g., organic matter content, iron speciation, and trace metal distributions) and careful consideration of possible post-deposition alteration will be required to avoid spurious interpretation of 238U/235U data from ancient carbonate sediments.

Geochemistry and isotopic composition of gabbros from ODP Hole 118-375B

Gabbros drilled from the shallow (720 m) east wall of the Atlantis II transform on the Southwest Indian Ridge (SWIR; 32°43.40', 57°16.00') provide the most complete record of the stratigraphy and composition of the oceanic lower crust recovered from the ocean basins to date. Lithologies recovered include gabbro, olivine gabbro, troctolite, trondhjemite, and unusual iron-titanium (FeTi) oxide-rich gabbro containing up to 30% FeTi oxides. The plutonic rock sequence represents a tholeiitic fractionation trend ranging from primitive magmas having Mg numbers of 67 to 69 that fractionated troctolites, to highly evolved liquids that crystallized two-pyroxene, FeTi oxide-rich gabbros and, ultimately, trondhjemite. Isotopic compositions of unaltered Leg 118 gabbros are distinct from Indian Ocean mid-ocean ridge basalts (MORB) in having higher 143Nd/144Nd (0.51301-0.51319) and lower 206Pb/204Pb values (17.35-17.67); 87Sr/86Sr values (0.7025-0.7030) overlap those of SWIR basalts, but are generally lower than MORBs from the Southeast Indian Ridge or the Rodrigues Triple Junction. More than one magma composition may have been introduced into the magma chamber during its crystallization history, as suggested by the higher 87Sr/86Sr, 206Pb/204Pb, and lower 143Nd/144Nd values of chromium-rich olivine gabbros from the bottom of Hole 735B. Whole-rock gabbro and plagioclase mineral separate 87Sr/86Sr values are uniformly low (0.7027-0.7030), irrespective of alteration and deformation. By contrast, 87Sr/86Sr values for clinopyroxene (0.7025-0.7039) in the upper half of Hole 735B are higher than coexisting plagioclase and reflect extensive replacement of clinopyroxene by amphibole. Hydrothermal veins and breccias have elevated 87Sr/86Sr values (0.7029-0.7035) and indicate enhanced local introduction of seawater strontium. Oxygen- and hydrogen-isotope results show that secondary amphiboles have uniform dD values of -49 to -54 per mil and felsic hydrothermal veins range from -46 to - 77 per mil. Oxygen-isotope data for secondary amphibole and visibly altered gabbros range to low values (+1.0-+5.5 per mil), and O-isotope disequilibrium between coexisting pyroxene and plagioclase pairs from throughout the stratigraphic column indicates that seawater interacted with much of the gabbro section, but at relatively low water/rock ratios. This is consistent with the persistence of low 87Sr/86Sr values, even in gabbros that were extensively deformed and altered.