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  • Sediment cores were collected from the East Antarctic margin, aboard the Australian Marine National Facility R/V Investigator, during the IN2017_V01 voyage from January 14th to March 5th 2017 (Armand et al., 2018). This marine geoscience expedition, named the “Sabrina Sea Floor Survey”, focused notably on studying the interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles. The cores were collected using a multi-corer (MC), were sliced every centimetre, wrapped up in plastic bags, and stored in the fridge. Back at the home laboratory (IMAS, UTAS, Hobart, Australia), sediment samples were dried in an oven at 40°C. Three hundred mg of dry sediment was then homogenised and vortexed for 10-sec with 12 mL of a reductive solution of 0.005M hydroxylamine hydrochloride (HH) / 1.5% Acetic Acid (AA) / 0.001M Na-EDTA / 0.033M NaOH, at pH 4 (Huang et al., 2021). The leach mixture was then centrifuged, and 6 mL of the supernatant solution was collected into a Teflon vial. This solution was taken to dryness, oxidized with 1 mL HNO3 + 100 µL H2O2, and redissolved in 4 mL of 7.5M HNO3. A 0.5 mL aliquot was separated from the 4 mL solution for trace metal analysis by Sector Field Inductively Coupled Mass Spectrometry (SF-ICP-MS, Thermo Fisher Scientific, Bremen, Germany) at the Central Science Laboratory (UTAS, Hobart, Australia). Indium was added as internal standard (In, 100 ppb). 88Sr, 89Y, 95Mo, 107Ag, 109Ag, 111Cd, 133Cs, 137Ba, 146Nd, 169Tm, 171Yb, 185Re, 187Re, 205Tl, 208Pb, 232Th, 238U, 23Na, 24Mg, 27Al, 31P, 32S, 42Ca, 47Ti, 51V, 52Cr, 55Mn, 56Fe, 59Co, 60Ni, 63Cu and 66Zn were analysed using multiple spectral resolutions. Element quantification was performed via external calibration using multi-element calibration solutions (MISA suite, QCD Analysts, Spring Lake, NJ, USA). Raw intensities were blank and dilution corrected. References Armand, L. K., O’Brien, P. E., Armbrecht, L., Baker, H., Caburlotto, A., Connell, T., … Young, A. (2018). Interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles (IN2017-V01): Post-survey report. ANU Research Publications, (March). https://doi.org/http://dx.doi.org/10.4225/13/5acea64c48693 Huang, H., Gutjahr, M., Kuhn, G., Hathorne, E. C., and Eisenhauer, A. (2021). Efficient Extraction of Past Seawater Pb and Nd Isotope Signatures From Southern Ocean Sediments. Geochemistry, Geophysics, Geosystems, 22(3), 1–22. https://doi.org/10.1029/2020GC009287

  • Oceanographic processes in the subantarctic region contribute crucially to the physical and biogeochemical aspects of the global climate system. To explore and quantify these contributions, the Antarctic Cooperative Research Centre (CRC) organised the SAZ Project, a multidisciplinary, multiship investigation carried out south of Australia in the austral summer of 1997-1998. Taken from the abstracts of the referenced papers: The SAZ project organised by the Antarctic CRC has a continuing program of moored sinking particle trap studies in the Aub-Antarctic and Polar Frontal zones southwest of Tasmania along 140 degrees E. The first deployment obtained weekly or higher resolution samples through the austral summer from September 1997 through February 1998 at three locations: the central Sub-Antarctic Zone (47 degrees S, traps at 1000, 2000 and 3800 m depth), the Sub-Antarctic Front (51 degrees S, 1 trap at 3300 m) and above the Southeast Indian Ridge in the Polar Frontal Zone (54 degrees S, 2 traps at 800 and 1500 m). The particles were analysed for total mass, inorganic carbon, total carbon, nitrogen, silicon, and aluminium. Hence values for organic carbon, biogenic silica, and lithogenics were obtained, and the mass fluxes calculated. This report details the sites, moorings, data from the current meters and sediment traps, and results of analyses performed on the collected sediment trap material. Sediment trap moorings were deployed from September 21, 1997 through February 21, 1998 at three locations south of Australia along 140 degrees E: at -47 degrees S in the central Subantarctic Zone (SAZ) with traps at 1060, 2050, and 3850 m depth, at-51 degrees S in the Subantarctic Front with one trap at 3080m, and at -54 degrees S in the Polar Front Zone(PFZ) with traps at 830 and 1580m. Particle fluxes were high at all the sites (18-32gm-2 yr-1 total mass and 0.5-1.4g organic carbon m-2 yr-1 at ~1000m, assuming minimal flux outside the sampled summer period). These values are similar to other Southern Ocean results and to the median estimated for the global ocean by Lampitt and Antia [1997], and emphasise that the Southern Ocean exports considerable carbon to the deep sea despite its "high-nutrient, low chlorophyll" characteristics. The SAZ site was dominated by carbonate (greater than 50% of total mass) and the PFZ site by biogenic silica (greater than 50% of total mass). Both sites exhibited high export in spring and late summer, with an intervening low flux period in December. For the 153 day collection period, particulate organic carbon export was somewhat higher in all the traps in the SAZ (range 0.57-0.84 gC m -L) than in the PFZ (range 0.31-0.53), with an intermediate value observed at the SAF (0.60). The fraction of surface organic carbon export (estimated from seasonal nutrient depletion, Lourey and Trull [2001]) reaching 1000 m was indistinguishable in the SAZ and PFZ, despite different algal communities.

  • Marine sediments often represent an important reservoir of carbonate minerals that will react rapidly to changing seawater chemistry as a result of ocean acidification. Ocean acidification (the reaction of CO2 with seawater) lowers the saturation state with respect to carbonate minerals and may lead to dissolution of these minerals if undersaturation occurs. There are three main carbonate minerals found in marine sediments: 1. aragonite 2. calcite (also referred to as low-magnesium calcite, containing less than 4mol% MgCO3) 3. high-magnesium calcite (greater than 4 mol% MgCO3) Due to the different structure of these minerals, they have different solubilities with high-Mg calcite the most soluble, followed by aragonite and then calcite. As seawater CO2 increases and the saturation state with respect to carbonate minerals decreases, high-Mg calcite will be the first mineral subject to undersaturation and dissolution. By measuring the carbonate mineral composition of sediments, we can determine which areas are most at risk from dissolution. This information forms an important baseline with which we can assess future climate change. The effect of ocean acidification on carbonates in marine sediments will occur around the world, but due to the lower seawater temperatures in Antarctica, solubility is much lower so the impacts will occur here first. This dataset is a compilation of carbonate mineralogy data from surface sediments collected from the East Antarctic margin. The dataset includes sample metadata, bulk carbonate content, %calcite, % aragonite and mol% MgCO3 (i.e. the magnesium content of high-Mg calcite). This dataset was compiled from new (up to 2020) and archived sediment samples that contacted sufficient carbonates (typically greater than 3% CaCO3)/

  • This metadata record contains an Excel file containing total petroleum hydrocarbon data from analysis of marine sediments collected at Davis Station from December 2009 to March 2010. Refer to the Davis STP reports lodged under metadata record Davis_STP for the full Davis Sewage Treatment Project methods and result details. Davis STP - Total petroleum hydrocarbons Hydrocarbons were extracted from a 10g sub-sample of homogenised wet soil by tumbling overnight with a mixture of 10 mL of deionised water, 10 mL of dichlormethane (DCM), and 1 mL of DCM spiked with internal standards: 254 mg/L bromoeicosane; 55.2 mg/L 1,4 dichlorobenzene; 51.2 mg/L p-terphenyl; 52.2 mg/L tetracosane-d50; and 255 mg/L cyclo-octane. Samples were then centrifuged for 5 minutes at 1000 rpm, this was repeated a further 3 times to ensure complete separation of the organic and aqueous fractions. The DCM fraction was then extracted and placed into GC-vials. Extracts were analysed for total petroleum hydrocarbons (TPH) by gas chromatography using flame ionisation detection (GC-FID; Agilent 6890N with a split/splitless injector) and an auto-sampler (Agilent 7683 ALS). Separation was achieved using an SGE BP1 column (25 m x 0.22 mm ID, 0.25 µm film thickness). 1 µL of extract was injected (5:1 pulsed split) at 310° C and 17.7 psi of helium carrier gas. After 1.3 minutes, the carrier gas pressure was adjusted to maintain constant flow at 3.0 mL/min for the duration of the oven program. The oven temperature program was started at 36 °C (held for 3 minutes) and increased to 320 °C at 18 °C/min. Detector temperature was 330 °C. TPH concentrations were determined using a calibration curve, generated from standard solutions of special Antarctic blend diesel (SAB), and standard diesel. TPH was measured using the ratio of the total detector response of all hydrocarbons to the internal standard peak response. List of compounds analysed - C8-C28 individual hydrocarbon components - Naphthalene - Biomarkers (phytanes) - Total signal and area, and resolved compounds from C8 to C40, over specific ranges (e.g. C9-C18, SAB) Reporting limit - 0.3 mg.kg-1 on a dry matter basis (DMB) for individual components - 2.5-160 mg.kg-1 on a dry matter basis (DMB) for various calculated ranges Analytical uncertainty - Analytical precision: (a) 3 samples extracted and analysed in triplicate, (b) 3 extracts analysed by GC-FID in duplicate; only 1 of each set greater than RL (160): (a) RSD = 2%, (b) RSD = 0.4% - Site heterogeneity: reproducibility (RSD) of mean data from site replicate samples (mostly duplicates) was 24% (mean, SD 20%, range 4-60%, n=8) - From the limited data on reproducibility summarised above, it can be concluded that site heterogeneity contributes most to the uncertainty of the TPH data for the site locations. Background of the Davis STP project Refer to the Davis STP reports lodged under metadata record Davis_STP.

  • This is a scanned copy of the report of sediment core activities at Davis Station, 1985 by Lin Jian-ping. Paraphrased from the abstract of the report: Sediment deposited in the bottom of water provide a historical record of the biological and chemical changes which have occurred in the places since they were formed. One of the research programs at Davis in 1985 was the sediment coring program. Sediment cores were taken from some places of the Vestfold Hills, Antarctica, and were analysed for water content, total organic content and non-polar lipid content.

  • Sediment cores were collected from the East Antarctic margin, aboard the Australian Marine National Facility R/V Investigator from January 14th to March 5th 2017 (IN2017_V01; Armand et al., 2018). This marine geoscience expedition, named the “Sabrina Sea Floor Survey”, focused notably on studying the interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles. The cores were collected using a multi-corer, allowing to sample the surface of the sediment (top ~ 30cm). The cores were then sliced every centimetre, wrapped up in plastic bags, and stored in the fridge. Radiocarbon (14-C) ages were measured to build an age model for future paleo-reconstructions. Sediment samples were pre-treated in the IMAS Sediment Lab (UTAS, Hobart, Australia). Samples (~ 2 g) from the multi-cores MC01, MC03 and MC06 were dried, ground and acidified with HCl for carbonate removal using sterilised beakers. Dried and ground samples were then packed into sterilised aluminium foil and sent to DirectAMS (Radiocarbon Dating Service, USA) for 14C analysis by Accelerator Mass Spectrometer (AMS). Results were corrected for isotopic fractionation with an unreported δ13C value measured on the prepared carbon by the accelerator. References L.K. Armand, P.E. O’Brien and On-board Scientific Party. 2018. Interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles (IN2017-V01): Post-survey report, Research School of Earth Sciences, Australian National University: Canberra.

  • Environmental descriptors that are available for the study area (-180 degrees W/+180 degrees E; -45 degrees/-78 degrees S) and for the following periods: 1955-1964, 1965-1974, 1975-1984, 1985-1994, 1995-2012. They were compiled from different sources and transformed to the same grid resolution of 0.1 degree pixel. We also provide future projections for environmental descriptors established based on the Bio-Orable database (Tyberghein et al. 2012). They come from IPCC scenarii (B1, AIB, A2) for years 2100 and 2200 (IPCC, 4th report).

  • Sediment cores were collected from the East Antarctic margin, aboard the Australian Marine National Facility R/V Investigator from January 14th to March 5th 2017 (IN2017_V01; Armand et al., 2018). This marine geoscience expedition, named the “Sabrina Sea Floor Survey”, focused notably on studying the interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles. The cores were collected using a multi-corer (MC) and a Kasten corer (KC). The MC were sliced every centimetre, wrapped up in plastic bags, and stored in the fridge. The KC was sub-sampled using an u-channel; and sliced every centimetre once back the home laboratory (IMAS, UTAS, Hobart, Australia). This dataset presents concentrations of major and trace elements measured in bulk multi-cores sediment samples collected during the IN2017_V01 voyage. The data include the sampling date (day/month/year), the latitude and longitude (in decimal degrees), the seafloor depth (in meter), the sediment core ID, the sediment depth (in cm), and the concentrations (in ppm or μg/g) of a suite of elements. This dataset presents concentrations of major and trace elements measured in bulk sediment samples collected during the IN2017_V01 voyage. The data include the sampling date (day/month/year), the latitude and longitude (in decimal degrees), the seafloor depth (in meter), the sediment core ID (KC14), the sediment depth (in cm), and the concentrations (in ppm or μg/g) of a suite of elements. About 200 mg of dried and ground sediment were weighed into a clean Teflon vial and oxidized with a mixture of concentrated HNO3 and 30% H2O2 (1:1). Samples were then digested in open vials using an acid mixture comprising 10 mL HNO3, 4 mL HCl, and 2 mL HF, at 180°C until close to dryness. Digested residues were converted to nitric form before being oxidised with a mixture of 1 mL HNO3 and 1 mL HClO4 at 220°C until fully desiccated. Samples were finally re-dissolved in 4 mL 7.5 M HNO3. A 400 μL aliquot was removed from the 4 mL digest solution and diluted ~2500 times in 2% HNO3 for trace metals analysis by Sector Field Inductively Coupled Mass Spectrometry (SF-ICP-MS, Thermo Fisher Scientific, Bremen, Germany) at the Central Science Laboratory (UTAS, Hobart, Australia). Indium was added as internal standard (In, 100 ppb). 88Sr, 89Y, 95Mo, 107Ag, 109Ag, 111Cd, 133Cs, 137Ba, 146Nd, 169Tm, 171Yb, 185Re, 187Re, 205Tl, 208Pb, 232Th, 238U, 23Na, 24Mg, 27Al, 31P, 32S, 42Ca, 47Ti, 51V, 52Cr, 55Mn, 56Fe, 59Co, 60Ni, 63Cu and 66Zn were analysed using multiple spectral resolutions. Element quantification was performed via external calibration using multi-element calibration solutions (MISA suite, QCD Analysts, Spring Lake, NJ, USA). Raw intensities were blank and dilution corrected. References L.K. Armand, P.E. O’Brien and On-board Scientific Party. 2018. Interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles (IN2017-V01): Post-survey report, Research School of Earth Sciences, Australian National University: Canberra.

  • Underwater video samples were obtained from the Deep Underwater Camera II (DUCII) system. Data are in mpeg video format. Samples were named by: 1. CEAMARC site (e.g. 16) 2. Instrument (e.g. camera = CAM) 3. Sequence of deployments through the survey overall (e.g. first deployment = 01; second deployment = 02) e.g. 09CAM05 is the fifth camera deployment of the survey overall, and was at CEAMARC site 09. Post-cruise analyses: 15 second logging of seabed geology and biology (species, class, order, whatever is significant for the habitat) directly into GNAV software for overlay into a GIS.

  • This dataset was collected as part of an honours project by Jessica Wilks at Macquarie University (submitted May 2012). The samples analysed were taken from an expedition conducted by Dr Leanne Armand in 2011 as part of the KEOPS2 mission (KErguelen: compared study of the Ocean and the Plateau in Surface water). During this mission 7 locations (A3-1, A3-2, E1-3, E14W2, NPF-L, R2 and TEW) around the Kerguelen Plateau were sampled for seafloor sediment. This study involved identification of over 50 species of diatoms as part of a species assemblage/ distribution study. A photograph of each diatom encountered in this study is included in the attached plates.