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  • Trace metal concentrations are reported in micrograms per gram of sediment in core C012-PC05 (64⁰ 40.517’ S, 119⁰ 18.072’ E, water depth 3104 m). Each sediment sample (100-200mg) was ground using a pestle and mortar and digested following an initial oxidation step (1:1 mixture of H2O2 and HNO3 acid) and open vessel acid on a 150 degree C hotplate using 2:5:1 mixture of concentrated distilled HCl, HNO3 and Baseline Seastar HF acid. After converting the digested sample to nitric acid, an additional oxidation step was performed with 1:1 mixture of concentrated distilled HNO3 and Baseline Seastar HClO4 acid. A 10% aliquot of the final digestion was sub-sampled for trace metal analyses. Trace metal concentrations were determined by external calibration using an ELEMENT 2 sector field ICP-MS from Thermo Fisher Scientific (Bremen, Germany) at Central Science Laboratory (University of Tasmania). The following elements were analysed in either low (LR) or medium resolution (MR): Sr88(LR), Y89(LR), Mo95(LR), Ag107(LR), Cd111(LR), Cs133(LR), Ba137(LR), Nd146(LR), Tm169(LR), Yb171(LR), Tl205(LR), Pb208(LR), Th232(LR), U238(LR), Na23(MR), Mg24(MR), Al27(MR), P31(MR), S32(MR), Ca42(MR), Sc45(MR), Ti47(MR), V51(MR), Cr52(MR), Mn55(MR), Fe56(MR), Co59(MR), Ni60(MR), Cu63(MR), Zn66(MR).

  • 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.

  • These data were generated by Raffaella Tolotti (raffaella.tolotti@virgilio.it) thanks to a scholarship founded by the Italian P.N.R.A. ‘TYTAN Project (PdR 14_00119): ‘Totten Glacier dYnamics and Southern Ocean circulation impact on deposiTional processes since the mid-lAte CeNozoic’ (Principal Investigator Dr. Donda Federica, Dr. Caburlotto A. - OGS, Trieste) and University of Genova (DISTAV - Prof. Corradi Nicola). These data are based on samples collected during research cruise IN2017_V01 of the RV Investigator, co-chief scientists, Leanne Armand and Phil O’Brien and were collected to provide paleoceanographic and bio/ stratigraphic information on Aurora Basin Antarctic margin evolution. The IN2017-V01post-cruise report is available through open access via the e-document portal through the ANU library. https://openresearch-repository.anu.edu.au/handle/1885/142525 The document DOI: 10.4225/13/5acea64c48693 The preferred citation are: 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, http://dx.doi.org/10.4225/13/5acea64c48693 Donda F., Leitchenkov, Brancolini G., Romeo R., De Santis L., Escutia C., O'Brien P., Armand L., Caburlotto, A., Cotterle, D., 2020. The influence of Totten Glacier on the Late Cenozoic sedimentary record. Antarctic Science, 1 -3; http://doi:10.1017/S0954102020000188 O’Brien, P.E., Post, A.L., Edwards, S., Martin, T., Carburlotto, A., Donda, F., Leitchenkov, G., Romero, R., Duffy, M., Evangelinos, D., Holder, L., Leventer, A., López-Quirós, A., Opdyke, B.N., and Armand, L.K. in press. Continental slope and rise geomorphology seaward of the Totten Glacier, East Antarctica (112°E-122°E). Marine Geology. Samples for diatom analysis were collected on board ship immediately after core recovery. Sub-samples were sent, according to the Australian standard procedures, to the DISTAV sedimentological laboratory in Genoa (Italy) and prepared for the micro-paleontological analysis according to the laboratory’s protocol (imported and tested from Salamanca University lab.; Referring Prof. Bárcena). Smear-slides and the qualitative-quantitative analyses were performed every 20 cm. Previous onboard smear slides analyses on PC03 highlighted notable variations from the other piston cores, containing some older diatom species. Moreover this core exceptionally did not exhibit a clear cyclicity like the others. It was so assumed to target a condensed sedimentary sequence giving access to older sediments. The further, more in-depth diatom biostratigraphic and quantitative analyses were performed in accordance with the international stratigraphic guide (https://stratigraphy.org/guide/), with the pluri-decennial DSDP and IODP Antarctic diatom biostratigraphic reports and specific papers (see References). Sample preparation, diatom species identification and counting were those described in Schrader and Gersonde (1978), Barde (1981 - modified) and Bodén (1991). Diatom analysis was performed with an immersion 1000x LM Reichert Jung-Polyvar microscope (Wien). Whenever possible, almost 300 diatom valves were counted per slide following the counting methodology presented in Schrader and Gersonde (1978). When diatom concentration proved too low or too concentrated, slides with modified concentrations have been prepared to optimize counting and identification while at least one hundred fields-of-view per poor concentration slide have been analyzed. For samples that were too diatom-poor, the over-concentration of material on the slides resulted in limiting resolution and taxonomic identification of the rare and mostly fragmented valves. Where diatom occurrence was rare only major fragments (>50%) or entire valves were counted. The file (.xls) contains 2 sheets: Sheet: PC03 diatoms dataset. The absolute diatom valve concentration (ADA= Absolute Valves Abundance) was then calculated following Abrantes et al. (2005), Warnock and Scherer (2014) and ADA in Taylor, Silva and Riesselmann (2018), taking in account initial weights, concentration of the samples and microscope’s characteristics, as the number of valves per gram of dry sediment. Diatoms were identified to species level following Crosta et al. (2005), Armand et al. (2005), Cefarelli et al. (2010) for modern assemblages. Older diatom taxa were identified following Gersonde et Bárcena, 1998, Witkowski et al., 2014; Bohaty et al., 2011; Gombos, 1985; Gombos, 2007; Gersonde et al., 1990; Barron et al., 2004; Harwood et al., 2001; Harwood etal., 1992. Species were considered extinct when observed stratigraphically higher than extinction boundaries as identified by Cody et al. (2008) but the coexistence or the alternation in the stratigraphic sequence of taxa referring to different biostratigraphic age ranges were considered signs of reworking. Sheet: PC03 tephra dataset. During LM microscopic observations some volcanic glass shards were observed first in smear slides and then counted during the activities of microfossils count for diatoms. This allowed to obtain the number of glass shards/g. dry sed. useful to compare with diatom and sediment datasets. Core location: Station_core Longitude Latitude A006_PC03 115.043 -64.463 Depth: The core was taken at Site A006 that was chosen into an overbank deposit on the upper western side of a turbidite channel (Minang-a Canyon) (Fig. 39 – Armand et al., 2017; O’Brien et al., 2020). The setting is at 1862 m depth, shallower respect the other cores. A possible higher energy environment, with a lower sedimentation rate has been first supposed. Temporal coverage: Start date: 2017-01-14 - Stop date: 2018-11-30 References: Armand, L.K., X. Crosta, O. Romero, J. J. Pichon (2005). The biogeography of major diatom taxa in Southern Ocean sediments: 1. Sea ice related species, Paleogeography, Paleoclimatology, Paleoecology, 223, 93-126. Cefarelli, A.O., M. E. Ferrario, G. O. Almandoz, A. G. Atencio, R. Akselman, M. Vernet (2010). Diversity of the diatom genus Fragilariopsis in the Argentine Sea and Antarctic waters: morphology, distribution and abundance, Polar Biology, 33(2), 1463-1484. Cody, R., R. H. Levy, D. M. Harwood, P. M. Sadler (2008). Thinking outside the zone: High-resolution quantitative diatom biochronology for the Antarctic Neogene, Palaeogeography, Palaeoclimatology, Palaeoecology, 260, 92-121; doi:10.1016/j.palaeo.2007.08.020 Crosta, X., O. Romero, L. K. Armand, J. Pichon (2005). The biogeography of major diatom taxa in Southern Ocean sediments: 2. Open ocean related species, Palaeogeography, Palaeoclimatology, Palaeoecology, 223, 66-92. Rebesco, M., E. Domack, F. Zgur, C. Lavoie, A. Leventer, S. Brachfeld, V. Willmott, G. Halverson, M. Truffer, T. Scambos, J. Smith, E. Pettit (2014). Boundary condition of grounding lines prior to collapse, Larsen-B Ice Shelf, Antarctica, Science, 345, 1354-1358. Warnock, J. P., R. P. Scherer (2014). A revised method for determining the absolute abundance of diatoms, J. Paleolimnol.; doi:10.1007/s10933-014-9808-0 Witkowski, J., Bohaty, S.M., McCartney, K., Harwood, D.M., (2012) . Enhanced siliceous plankton productivity in response to middle Eocene warming at Southern Ocean ODP Sites 748 and 749 Palaeogeog., Palaeoclimat., Palaeoecol., 326–328, 78–94; doi:10.1016/j.palaeo.2012.02.006 Witkowski, J., Bohaty, S.M., Edgar, K.M., Harwood, D.M., (2014). Rapid fluctuations in mid-latitude siliceous plankton production during the Middle Eocene Climatic Optimum (ODP Site 1051, Western North Atlantic). Mar. Micropal., 106, 110–129. http://dx.doi.org/10.1016/j.marmicro.2014.01.001 Raffaella Tolotti unpublished data

  • 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), 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 sediment was then leached a second time (to ensure the removal of all oxides and excess minerals, i.e. to isolate the detrital fraction) with 15 mL of 0.02M HH, 25% AA solution and agitated using a rotisserie (20 rpm) overnight (Wilson et al., 2018). Samples were then centrifuged, rinsed with Milli-Q water 3 times, and dried in an oven at 50°C. About 50 mg of resulting dry (detrital) sediment was ground, weighed into a Teflon vial, and digested with a strong acid mixture. First, the sediment was oxidized with a mixture of concentrated HNO3 and 30% H2O2 (1:1). Samples were then digested in open vials using 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 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 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. Wilson, D. J., Bertram, R. A., Needham, E. F., van de Flierdt, T., Welsh, K. J., McKay, R. M., … Escutia, C. (2018). Ice loss from the East Antarctic Ice Sheet during late Pleistocene interglacials. Nature, 561(7723), 383.

  • Twenty-six marine and lacustrine sediment cores were taken from Windmill Islands during the 1998/99 season. They have been analysed for physical, chemical and biological parameters by a multidisciplinary team under ASAC project 1071. The download file contains 12 Excel spreadsheets of data.

  • 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. Each attached spreadsheet represents the data from one of these locations. Three tubes of sediment were taken for each location. The data within each spreadsheet is separate for the three tubes. After the tubes of seafloor sediment were processed to remove organic material and carbonates (leaving nothing but siliceous material, primarily diatoms) slides were made with a small amount of material, three slides per tube of sediment. Diatoms were identified using a light microscope at 40x magnification. Approximately 400 frustules were counter per tube (ie per set of 3 slides) in order to represent the diversity of the species present. The number of each species or subspecies of diatom are tallied in the spreadsheets attached. Species identifications follow Armand et al 2008. Other information in the attached spreadsheets includes the seafloor depth at the point of sampling, the distance from the Kerguelen shoreline at the point of sampling, the amount of suspended material used on each slide, the number of field of view (at 40X) viewed to count the quota of 400 diatom frustules, and the calculated number of frustules/ gram of dry sediment weight. Counting protocol: centric frustules were counted only when 1) more than half of the frustule was intact; and 2) the frustule was clearly identifiable. If 1) but not 2) then the frustule was counted as "unidentified centric". For Rhizosolenia spp, frustules were couned if the apex was present and identifiable, otherwise it was counted as "R. unknown". Thalassiothrix and Tricotoxon were only counted if one end was present and identifiable. The number was later divided by 2, to give the number of complete frustules. Abbreviations: A. spp= Actinocyclus As. spp= Asteromphalus Az. spp= Azpeita Ch. spp= Chaetoceros Co. spp= Coscinodiscus C. spp= Cocconeis D. spp= Dactyliosen E. spp= Eucampia F. spp= Fragilariopsis O. spp= Odontella P. spp= Paralia Po. spp= Porosira R. spp= Rhizosolenia Th. spp= Thalassionema T. spp= Thalassiosira Locations A3-1, Kerguelen Plateau: -50.65333 S, 72.04 E A3-2, Kerguelen Plateau: -50.64722 S, 72.07 E E1-3, Kerguelen Plateau: -48.11667 S, 71.96667 E E14W2, Kerguelen Plateau: -48.7775 S, 71.43833 E NPF-L, Kerguelen Plateau: -48.62417 S, 74.81222 E R2, Kerguelen Plateau: -50.39389 S, 66.69944 E TEW, Kerguelen Plateau: -49.16083 S, 69.83389 E

  • These data are linked to what appears to be an unfinished report/paper by Pat Quilty. An extract of the unfinished report is available below, and the full document is included in the data download. These data are also linked to a collection in the biodiversity database, and are also related to another record (both listed at the provided URLs). Foraminiferids are recorded from samples collected on Mac. Robertson Shelf and Prydz Bay, East Antarctica in 1982, 1995 and 1997. Most are identifiable from previous literature but a new enrolled biserial agglutinated genus is noted but not defined. Distribution is related to oceanographic factors. The Mac. Robertson Shelf-Prydz Bay region off the East Antarctic coast is that segment of the southern Indian Ocean between latitudes 66 degrees and almost 70 degrees S, and longitudes 60 degrees and 80 degrees E. It includes Mac. Robertson Shelf, the continental shelf, bounded seaward by the 500 m isobath, and Prydz Bay, the deepest re-entrant into the east Antarctic shield and the outlet for the Lambert Glacier at its southern end. The Lambert Glacier is the world’s largest glacier and drains some 1 000 000 km2 of East Antarctica. The marine region studied here covers some 140 000 km2. Several research cruises to the region have collected sediment samples that yielded modern and recycled foraminiferid faunas. The modern component of the faunas has not been recorded in detail previously. This paper records the details of the taxonomy and distribution of species collected during marine geology/geophysics cruises that provided the foraminiferids discussed in Quilty (1985, 2001), O’Brien (1992), O’Brien et al. (1993, 1995) and Harris et al. (1997). The geophysical results and interpretations of the 1982 voyage of MV Nella Dan are described by Stagg (1985) and this provides also the general setting and nomenclature of Prydz Bay. Two cruises (1995 and 1997) of RSV Aurora Australis collected samples and these provided the basis for Quilty’s records of foraminiferids and other components on a sample-by-sample basis in O’Brien et al. (1995) from 51 samples, and from a further 27 samples reported in Harris et al. (1997). The 1995 cruise also yielded the recycled foraminifera recorded by Quilty (2001) and the Mesozoic material documented by Truswell et al. (1999). Neither of these cruise records provided details of the faunas to the level covered here. Further studies for the region are given in the results of ODP Legs 119 and 188. The impetus for conducting this review comes from two sources. Firstly, few foraminiferids have been documented from this region, and even fewer have been figured. Secondly, 2007-2008 was designated the [fourth] International Polar Year (IPY) and one of the major programs is the Census of Antarctic Marine Life (CAML), a component of the global Census of Marine Life (CML). This paper is a contribution to that project. Included in the review are faunas from the modern environment and some which may be ‘Late Cenozoic’ in which the faunas are of the same species as the modern and in which data from the modern can be, and have been, used to infer past environments (Fillon 1974, Kellogg et al. 1979, Ward and Webb 1986). The aims of this paper are: - to document the species of foraminifera recovered from geology/geophysics cruises to the Mac. Robertson Shelf and Prydz Bay region, offshore East Antarctica (Fig. 1); - to make the nomenclature of species recorded consistent with latest taxonomic practice; - to characterise the faunas by diversity and dominance factors; and - to discuss the controls on the distribution of faunas recorded.

  • Total Organic Carbon A 2 g homogenised wet sediment sub-sample from each core was weighed into a pre-combusted crucible and dried at 105 degrees C. The dried sample was reweighed before being analysed for total carbon by mass loss on ignition at 550 degrees C, the sample was placed in the muffle furnace for 4 hours. Samples 56698, 57062, 56837, 57058, and 580792 were analysed in triplicate to assess the reproducibility of the analytical procedure. (Total number of analyses was 117). - TOC - For the 107 samples: - Mean and SD: 3 plus or minus 4 % DMB, range: 0.16-15 %, n=107 - Considering the mean values for the 27 site locations: - Range: 0.33-14 % DMB, mean and SD: 3.3 plus or minus 3.7 % DMB, n=27 - Analytical uncertainty - Analytical precision: 5 samples analysed in triplicate: - RSD = 6 plus or minus 5% range 1-11%, n=5 - Site heterogeneity: reproducibility (RSD) of mean data from site replicate samples was 26% (mean, SD 15%, range 10-57%, n=27) - From the limited data on reproducibility summarised above, it can be concluded that site heterogeneity contributes most to the uncertainty of the TOC data for the site locations. - DMF - For the 107 samples: - Mean and SD: 0.57 plus or minus 0.23 %, range: 0.09-0.85, n=107 - Considering the mean values for the 27 site locations: - Range:0.17-0.83, mean and SD: 0.57 plus or minus 0.22, n=27 - Analytical uncertainty - Analytical precision: 5 samples analysed in triplicate: - RSD = 2 plus or minus 2% range 0.8-5%, n=5 - Site heterogeneity: reproducibility (RSD) of mean data from site replicate samples (mostly quadruplicates) was 10% (mean, SD 10%, range 1-37%, n=27) - From the limited data on reproducibility summarised above, it can be concluded that site heterogeneity contributes most to the uncertainty of the DMF data for the site locations. Collection of sediment cores Sediment for grain size and various chemical analysis were sampled using a core of PVC tubing (15cm long x 5cm diameter) pushed 10cm into the sediment. These cores were kept upright at all times to ensure the stratigraphy remained intact and frozen in the core tube at -20 degrees C. Grain size analysis The outer 5 mm edge of the core was removed with a scalpel blade and placed in a clean, dried preweighed beaker. The sample was weighed and placed in an oven at 45 degrees C to dry. Once dry the sample was reweighed and then sieved through a 2 mm sieve, any residual sediment in the beaker was weighed and the weight recorded. The less than 2 mm fraction and the greater than 2 mm fraction were separately collected and weighed. A 5 g sample of the less than 2 mm fraction was taken for grain size analysis which was carried out using the Mastersizer 2000 Particle Size Analyser by Associate Professor Damian Gore at the Department of Physical Geography, Macquarie University, Sydney.

  • 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.