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

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.

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 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.

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.

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), 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). Sample residues 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 1% HNO3 for rare earth elements (REE) analysis by Sector Field Inductively Coupled Mass Spectrometry (SF-ICP-MS, Thermo Fisher Scientific, Bremen, Germany) at the Central Science Laboratory (UTAS, Hobart, Australia). Element quantification was performed via external calibration using multi-element calibration solutions (MISA-5, QCD Analysts, Spring Lake, NJ, USA). Samples were introduced to the instrument using an Aridius® II desolvating nebulizer (CETAC Technologies, USA). The DSN was tuned daily, and oxide formation for a range of test analytes (Ba, Ce, U etc) was always less than 0.05%. Isotopes 137Ba, 139La, 140Ce, 141Pr, 146Nd, 150Nd, 147Sm, 153Eu, 158Gd, 159Tb, 163Dy, 165Ho, 166Eu, 169Tm, 172Yb and 175Lu were monitored in low resolution mode. 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.

Marine sediment meiofauna community composition and sediment environmental data collected in 2005 and published in Stark, J. S., M. Mohammad, A. McMinn, and J. Ingels. 2020. Diversity, abundance, spatial variation and human impacts in marine meiobenthic nematode and copepod communities at Casey station, East Antarctica. Frontiers in Marine Science 7:480. From the abstract: The composition, spatial structure, diversity and abundance of Antarctic nematode and copepod meiobenthic communities was examined in shallow (5 – 25 m) marine coastal sediments at Casey Station, East Antarctica. The sampling design incorporated spatial scales ranging from 10 meters to kilometres and included testing for human impacts by comparing disturbed (metal and hydrocarbon contaminated sediments adjacent to old waste disposal sites) and control areas. A total of 38 nematode genera and 20 copepod families were recorded with nematodes being dominant, comprising up to 95% of the total abundance. Variation was greatest at the largest scale (km’s) but each location had distinct assemblages. At smaller scales there were different patterns of variation for nematodes and copepods. There were significant differences between communities at control and disturbed locations. Community patterns had strong correlations with concentrations of anthropogenic metals in sediments as well as sediment grain size and total organic content. Given the strong association with environmental patterns, particularly anthropogenic disturbance, meiofauna may be seen as very useful indicators of natural and anthropogenic environmental changes in Antarctica. Methods derived from: Stark, J. S., M. Mohammad, A. McMinn, and J. Ingels. 2020. Diversity, abundance, spatial variation and human impacts in marine meiobenthic nematode and copepod communities at Casey station, East Antarctica. Frontiers in Marine Science 7:480. Sampling design Sampling was undertaken using a hierarchical, nested design with three spatial scales, Locations (separated by kms); within each location there were two sites (~ 100 m apart) and at each site there were two plots (~10m apart). Within each plot (1m diameter), two replicate cores were taken for meiofauna and two for environmental analysis, making a total of 8 meiofauna and 8 environmental cores per location, except at O’Brien Bay-5 where one meiofauna core was lost during sampling. Six locations were sampled around Casey Station. There were three control locations, two of which were within O’Brien Bay to the south of Casey (O’Brien Bay-1 (OB-1) and O’Brien Bay-5 (OB-5)); and one within Newcomb Bay, in McGrady Cove (Fig. 1). There were three locations adjacent to waste disposal sites: two locations were situated along a gradient of pollution within Brown Bay (Inner and Middle)(Stark et al. 2004, Stark 2008); and a third location was at Wilkes, adjacent to the abandoned waste disposal site at the derelict Wilkes station (Stark et al. 2003a), all within Newcomb Bay (Fig. 1). These waste disposal sites were used historically to dispose of all waste and rubbish generated on station and included used oil, building materials, electronics and batteries, food, clothing and chemicals (Snape et al. 2001, Stark et al. 2006). Both waste disposal sites are contaminated with metals and hydrocarbons above background levels (Stark et al. 2008, Stark et al. 2014b, Fryirs et al. 2015). Sample collection, meiofauna preparation and identification Sediment samples were collected by divers using modified 60 ml syringes with their intake end cut off to form a small core tube (28mm internal diameter). Cores were pushed into the sediment to a depth of 10 cm, extracted, and the bottom end was capped. In a few cases samples were only taken down to 5-7 cm, where sediments were less than 10 cm deep due to underlying rock. No sediments less than 5 cm deep were sampled. Cores were transported to Casey Station laboratories where they were emptied into sample jars and 4% formalin was added to each sample. Prior to processing, each sample was washed through a 500 μm sieve to remove the macrofauna and the coarser sediment fraction. A 32 μm sieve was used to retain the meiofauna size fraction. Meiofauna were extracted through a modified gravity gradient centrifugation technique (Heip et al. 1985, Pfannkuche et al. 1988) using a % solution of Ludox HS40 and Ludox AS in distilled water (Witthoft-Muhlmann et al. 2005). Ludox is a silicasol (a colloidal solution of Si02) which causes no plasmolysis. Samples were rinsed thoroughly over a sieve of 32 µm with tap water to prevent flocculation of Ludox. The samples were then transferred from the sieve to a large centrifuge tube. Ludox was diluted with water to specific gravity 1.18 g/ml (60% Ludox and 40% water; density = 1.18) and added to each tube until the level of the mixture was balanced for centrifuging. The sample was then centrifuged at 2800 rpm for 10 min. The supernatant was decanted and collected, and the remaining sediment pellet was resuspended. This process was repeated three times. All supernatants were filtered on a 32 µm sieve, which was rinsed with tap water to avoid a reaction between the Ludox and formalin. After the extraction, 4% formalin and 1% of Rose Bengal (to facilitate counting) was added to preserve meiofauna before identification. Nematodes and copepods retained on the 32 µm sieve were counted and sorted using a dissecting microscope at 25X magnification (Zeiss Stemi 2000; Zeiss Inc., Germany). Two hundred nematodes per sample were picked out at random and mounted on slides in glycerine after a slow evaporation procedure (modified after Riemann, 1988) and identified to genus level using Platt and Warwick (1983, 1988) and Warwick et al. (1998) and NeMys online identification (Steyaert et al. 2005). All copepods were picked out and mounted on slides in glycerine without evaporation for identification to family level using THAO: the Taxonomische Harpacticoida Archiv Oldenburg 2005 and Bodin (1997). The identification of nematodes and copepods was conducted on a compound microscope (1000 x magnification). Environmental variables Sediment samples were taken for analysis of grain size, metals and total organic matter (TOM) using a 5 cm diameter core pushed 10 cm into the sediment. Cores were frozen at -20°C until analysis. Each core was subsampled from the top 5 cm of the frozen core, which was then homogenized by stirring and then subsampled further for separate analysis of grain size, metals and TOM. Full details of analytical methods can be found in Stark et al. (2014a) and are briefly summarised below. Total organic matter was calculated by mass-loss on ignition at 550 ° for four hours to determine ash free dry weight following Heiri et al. (2001), on a on a 2 g homogenised wet sub-sample, from 2 replicate cores in each plot for a total of 4 cores per location. Grain size analysis: The outer 5 mm edge of the top 5 cm of the core was removed with a scalpel blade and dried at 45 °C, then sieved through a 2mm sieve. The less than 2 mm fraction and the greater than 2 mm fraction were weighed separately. A 5 g sample of the less than 2mm fraction was analysed using a Mastersizer 2000 Particle Size Analyser with Hydro 2000MU accessory at the Department of Physical Geography, Macquarie University, Sydney. Analysis of metals in sediments were done on a 3 g sub-sample of homogenised wet sediment. A 1:10 w/v 1 M HCl digest was used as recommended by (Scouller et al. 2006), which gives an estimate of bioavailable elements and those more likely to have an anthropogenic source. Samples were analysed by ICP-MS at the Central Science Laboratories (CSL), University of Tasmania for a suite of ions which included: Sr, Mo, Ag, Cd, Sn, Sb, Pb, Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Al, Ba.