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    This dataset is derived from a comparative study evaluating six DNA extraction methods for their efficiency in recovering diatom sedimentary ancient DNA (sedaDNA) from Antarctic marine sediments. Sediment samples were collected from two sites: U1536C (Scotia Sea, West Antarctica) and KC02 (Sabrina Coast, Totten Glacier Region, East Antarctica). Each of the six extraction methods was applied to the same set of samples. Following shotgun metagenomic sequencing, the methods were assessed based on metrics such as diatom DNA recovery, average fragment length, and taxonomic diversity. The purpose of the study was to identify the optimal extraction approach for maximizing the yield and quality of diatom sedaDNA, thereby improving its utility for paleoenvironmental reconstruction.

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    The final lithospheric breakup of the Australian-Antarctic rift system remains controversial due to sparse geological constraints on the nature of the basement along the ocean-continent transition zones. We present new interpretations of multichannel seismic reflection transects, as well as new petrological data of dredged mantle rocks along the East Antarctic margin (Seamount B, offshore Terre Adélie). By combining both datasets, we show that a 50–100 km wide domain of cold (900°C), fertile subcontinental mantle was exhumed along the non-volcanic Antarctic margin. The dredged peridotites preserve characteristics similar to mantle xenoliths found in syn- to post-rift volcanism at the eastern end of the Australian margin (Victoria and Tasmania), indicating the sampling of a common fertile subcontinental mantle during rifting between Australia and Antarctica. Seamount B represents the initial stages of exhumation of cold subcontinental lithosphere along an ocean-continent transition during rifting. This thick mantle domain was likely affected by syn-rift melt impregnation at high-pressure (8 kbar), leading to the formation of plagioclase-pyroxenites. Overall, the combination of continental rifted blocks, a 50-100 km wide domain of volcanic-poor subcontinental mantle and (ultra)-slow spreading implies that ocean-continent transition zones along the Australian-Antarctic margins represent a recent analogue to ocean continent transition zones from the Jurassic Western Tethys. Additionally, evidence of syn-rift melt stagnation at high pressure suggests that magmatism along the Australian-Antarctic rifted margins was sufficient to form magnetic anomalies that can be used as isochrons despite their formation in lithosphere other than mature, steady-state ocean crust.

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    The East Antarctic Ice Sheet (EAIS) is the largest source of potential sea-level rise, containing some 19 m of sea-level equivalent. One of the well-investigated regions in East Antarctica is Law Dome, which is a small independent ice cap situated to the west of Totten Ice Shelf. The ice cap is slow-moving, has a low melt-rate at the surface and moderate wind speeds, making it a useful study site for our investigations. Radar data from Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP) project has good coverage over this area. A new method is proposed for the estimation of attenuation rate from radar data which is mathematically modeled as a constrained regularised l2 minimization problem. In the proposed method, only radar data is required and the englacial reflectors are automatically detected from the radar data itself. A final product of 3D attenuation rates and 3D samples count is provided for the research community in this data set.

  • Six dredges were undertaken from the RV Investigator during voyage IN2016_E01 to obtain rock and sediment samples to constrain the crustal nature, age of formation and paleo-environment through time of the Cascade Seamount, located offshore Eastern Tasmania, Australia. This record lists the sample number, weights and rock types recovered. In total we collected 713 kg of rock samples, including basalts, conglomerates, sandstones, limestones and tuffs.

  • Relevant spatial datasets for mapping pressures were identified and collated. Pressures were categorised as resource extraction and use, pollution, habitat modification, climate, and ‘other’. Pressures included Commonwealth trawl fisheries effort, aquaculture infrastructure, location of oil and gas infrastructure, historical shipping and pollution data, location of historical seismic operations, cyclone intensity, spoil dumping, sewage outfalls, location of ports, and tourism operations. Two main pressure maps were derived i) an additive pressure hotspots map, which gives higher weight to areas with multiple pressures of high risk; and, ii) a multiplicative hotspot pressure map, which gives lower weighting to areas with multiple low risk pressures. Areas of high risk were identified, and thus possibly high benefit for management versus low risk or low associated benefit for mitigation. The information generated needs to be considered alongside robust species distribution data and interaction matrices for effective decision-making.

  • An index of available 1 degree, 10 degree and 30 degree navigational S57 files that the Australian Hydrographic Service (AHS) holds. These were aggregated together to provide an overview for the NESP D3 Reef Project on potential sources of information.

  • The Marine Futures Project was designed to benchmark the current status of key Western Australian marine ecosystems, based on an improved understanding of the relationship between marine habitats, biodiversity and our use of these values. Approximately 1,500 km2 of seafloor were mapped using hydroacoustics (Reson 8101 Multibeam), and expected benthic habitats "ground-truthed" using towed video transects and baited remote underwater video systems. Both sources of information were then combined in a spatial predictive modelling framework to produce fine-scale habitat maps showing the extent of substrate types, biotic formations, etc. Surveys took place across 9 study areas, including the Capes region of southwest Western Australia. The area is one of the most diverse temperate marine environments in Australia. Warm, tropical waters of the Leeuwin Current mingle with the cool waters of the Capes Current, resulting in high finfish diversity, including tropical and temperate species, as well as internationally significant seagrass diversity with meadows occurring at depths greater than 40 metres. The region's geomorphology is complex with an array of intertidal and subtidal reef environments. Many marine plants and animals are endemic to the southern coast of Australia due to its long geographical isolation, with seagrass, algae and estuarine habitats functioning as spawning, nursery and feeding grounds for a wide range of invertebrates and fish. Significant numbers of marine mammals also frequent the area, including the blue whale, the largest of all marine creatures.

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    Dataset collected during two field campaigns in the same Antarctic fast ice site (Cape Evans, November/December 2018-19) as part of the AGP and NZARI collaboration over the grant "On Thin Ice: An in situ surveillance system for sea-ice microbial communities". The fieldwork was designed to test the scientific potentials of the IMAS/AGP developed under-ice HI system for mapping temporally dynamic and spatially varying under-ice habitats. The dataset consists of 3 terabytes of HI data acquired both in-situ under a wide range of natural and manipulated light conditions, as well as ex-situ with data acquired using a newly developed ice core scanning approach. The in-situ data are in the form of scanned transects acquired with a HI system capturing transmitted natural sunlight while being deployed beneath sea-ice. The ex-situ data was collected using external light sources illuminating horizontal and vertical sections of extracted ice cores. The dataset includes auxiliary data such as RGB imagery, TriOS RAMSES under-ice irradiance, sky irradiance, and any other measurements or information required to process the data. Other auxiliary data collected include filtered samples of ice core sections for fluorometric Chlorophyll-a (Chl-a) extraction, pigment composition via HPLC (to be processed), and particulate absorption spectra. Media footage (e.g., under-ice ROV videography, under-ice 360 videos, campaign photography of the systems and science) is also included. The dataset includes pre-processed high-resolution under-ice imagery collected from the fast-ice zone using a Sony a6300 camera mounted on a custom under-ice sled system. The imagery was acquired to document the sea-ice underside and analyse spatial patterns associated with amphipod communities from a near-horizontal, grazer-level perspective (publications pending).

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    These datasets compile rock physical properties from outcrops across the Bunger Hills oasis, Wilkes Land, East Antarctica, observed during the 2023–24 austral summer. Records include magnetic susceptibility (κ), radiogenic element concentrations (K, U, Th), and dry bulk density (rho), with station/sample identifiers, WGS84 coordinates, and per-record uncertainties. The compilation is intended to support regional geophysical interpretation and modeling, e.g., gravity-magnetic integration, crustal property mapping, and geothermal assessment. Data are provided as point observations without spatial interpolation. Dataset 'Petro_chem.xlsx' contains all insitu measurements in the field including calibration measurements (Start of the day: SOD, and End of day: EOD). Dataset 'DTC34-24_Sus_Density_HP.xlsx' contains density measurements on selected rock samples together with re-measured susceptibility and insitu co-located heat production measurements.

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    The Oceanic Shoals survey (SOL5650, GA survey 339) was conducted on the R.V. Solander in collaboration with Geoscience Australia, the Australian Institute of Marine Science (AIMS), University of Western Australia and the Museum and Art Gallery of the Northern Territory between 12 September - 5 October, 2012. This dataset comprises an interpreted geomorphic map. Interpreted local-scale geomorphic maps were produced for each survey area in the Oceanic Shoals Commonwealth Marine Reserve (CMR) using multibeam bathymetry and backscatter grids at 2 m resolution and bathymetric derivatives (e.g. slope; 1-m contours). Six geomorphic units; bank, depression, mound, plain, scarp and terrace were identified and mapped using definitions suitable for interpretation at the local scale (nominally 1:10 000). Maps and polygons were manual digitised in ArcGIS using the spatial analyst and 3D analyst toolboxes. For further information on the geomorphic mapping methods please refer to Appendix N of the post-survey report, published as Geoscience Australia Record 2013/38: Nichol, S.L., Howard, F.J.F., Kool, J., Stowar, M., Bouchet, P., Radke, L., Siwabessy, J., Przeslawski, R., Picard, K., Alvarez de Glasby, B., Colquhoun, J., Letessier, T. & Heyward, A. 2013. Oceanic Shoals Commonwealth Marine Reserve (Timor Sea) Biodiversity Survey: GA0339/SOL5650 Post Survey Report. Record 2013/38. Geoscience Australia: Canberra. (GEOCAT #76658).