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SEDIMENT CORERS

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  • 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.

  • 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. The sediment samples were dated using 210-Pb analysis for future paleo-reconstructions. 210-Pb is a radioisotope which allows to date sediment back to 150 years, which is ideal for surface (i.e. recent) sediment samples. Sediment samples were dried, ground and sent to Edith Cowan University (Joondalup, Western Australia) for sample preparation and analysis. Total 210Pb was determined through the analysis of its granddaughter 210Po by alpha spectrometry after complete sample digestion using an analytical microwave in the presence of a known amount of 209Po added as a tracer (Sanchez-Cabeza et al., 1998). The concentrations of excess 210Pb were determined as the difference between total 210Pb and 226Ra (supported 210Pb), the later determined by gamma spectrometry through the measurement of its decay products 214Pb and 214Bi using a HPGe detector (CANBERRA, Mod. SAGe Well). 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. Sanchez-Cabeza J. A., Masqué P. and Ani-Ragolta I. (1998) 210Pb and 210Po analysis in sediments and soils by microwave acid digestion. J. Radioanal. Nucl. Chem. 227, 19–22.

  • 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 (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.

  • 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

  • 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.

  • 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.

  • Ice-rafted debris is characterised by coarse material with typically angular grains, transported within icebergs and deposted in the ocean as the icebergs melt. This iceberg rafted debris (IBRD) flux data submitted here, was calculated by quantifying the coarse sand fraction (CSF) as a percentage of the bulk sample (weight of grains in the 250 micron to 2 mm size fraction), the dry bulk density (DBD) and the linear sedimentation rate (LSR) (following Krissek et al., 1995, Patterson et al., 2014). A method for quantifying the IBRD flux uses the coarse sand fraction (CSF) as a percentage of the bulk sample, dry bulk density (DBD) and the linear sedimentation rate (LSR) (Krissek et al., 1995, Patterson et al., 2014): The CSF (250μm-2mm) was acquired from samples at 10cm intervals along KC14 by wet-sieving approximately 20g of sediment per sample. Authigenic grains and microfossils were removed from the samples under a microscope. The remaining material was weighed on a microbalance and calculated as a percentage of the bulk sample. The DBD was calculated by subsampling approximately 8cm3 of sediment from the same depth intervals and dividing the dry weight of the sediment by the volume of the subsampler. The LSR was approximated by dividing the distance (cm) between the calibrated bulk carbon ages by the difference in time (kyr). The IBRD flux was then quantified using the above equation for each depth interval.

  • Depth related changes in sediment characteristics and the composition of infaunal invertebrate communities were investigated at two sites in the Windmill Islands around Casey station, East Antarctica, during the 2006/07 summer. Sediment characteristics were investigated via sediment cores (5cm deep x 5cm diameter) collected from 4 depths (7m, 11m, 17, and 22m) from each of three transects at two sites (McGrady Cove and O'Brien Bay 1). Measured sediment characteristics included grain size distribution, total organic carbon and the concentration of a range of heavy metals. This work was conducted as part of ASAC 2201 (ASAC_2201).