The Vlaming Sub-basin Marine Survey GA-0334 was undertaken in March and April 2012 as part of the Commonwealth Government's National CO2 Infrastructure Plan (NCIP). The purpose was to acquire geophysical and biophysical data to help identify sites suitable for the long term storage of CO2 within reasonable distances of major sources of CO2 emissions. This dataset contains identifications of animals collected from 32 Van Veen grabs deployed during GA-0334. Sediment was elutriated for ~ 5 minutes over a 500um sieve. Retained sediments and animals were then preserved in 70% ethanol for later laboratory sorting and identification (see `lineage'). During sorting, all worms were separated and sent to Infaunal Data Pty Ltd (Lynda Avery) for identification to species or operational taxonomic unit (OTU). Lynda Avery completed identifications on 17 April 2013, and specimens were lodged at the Museum of Victoria. All other taxa were identified to morphospecies at GA by an ecologist. Gray shading indicates taxa identified to species level by Lynda Avery (Refer to GeoCat # 76463 for raw data of species identifications by taxonomist); all other taxa were identified to morphospecies. Data is presented here exactly as delivered by the taxonomist/ecologist, and Geoscience Australia is unable to verify the accuracy of the taxonomic identifications. Stations are named XXGRYY where XX indicates the station number, GR indicates Van Veen grabs, and YY indicates the sequence of grabs deployed (i.e. the YYth grab on the entire survey). H indicates heavy fraction animals and HS indicates animals found on a sponge. The dataset is current as of November 2014, but will be updated as taxonomic experts contribute. See GA Record 2013/09 for further details on survey methods and specimen acquisition.

Permeable, sandy sediments cover most of the continental shelf. The important role of pore-water advective flow on biogeochemical processes in these sediments has been highlighted in recent studies. Such flow can be driven by wave-action, water-density and interactions between topography and bottom currents, in addition to biological activity, and can create spatially complex and highly dynamic benthic environments in which processes vary on timescales ranging from minutes to months. It is well known that the patchiness of soft sediment (organic matter/bacteria, particle diversity, redox) is likely to be a major determinant of species diversity, but previous studies have not specifically defined patches based on a range of biologically-relevant physico-chemical variables, nor observed how patches change across time. This study, as part of the Surrogates Program in the Commonwealth Environmental Research Facilities Marine Biodiversity Hub, investigated temporal changes in the geochemistry, physical sediments and infauna of sandy sediments in Jervis Bay at two times.

Geoscience Australia carried out marine surveys in Jervis Bay (NSW) in 2007, 2008 and 2009 (GA303, GA305, GA309, GA312) to map seabed bathymetry and characterise benthic environments through co-located sampling of surface sediments (for textural and biogeochemical analysis) and infauna, observation of benthic habitats using underwater towed video and stills photography, and measurement of ocean tides and wave-generated currents. Data and samples were acquired using the Defence Science & Technology Organisation (DSTO) Research Vessel Kimbla. Bathymetric mapping, sampling and tide/wave measurement were concentrated in a 3x5 km survey grid (named Darling Road Grid, DRG) within the southern part of the Jervis Bay, incorporating the bay entrance. Additional sampling and stills photography plus bathymetric mapping along transits was undertaken at representative habitat types outside the DRG. This 42 sample data set comprises the mineraology of surface seabed sediment (~0-2 cm) in Jervis Bay. More information: Radke, L.C., Huang, Z., Przeslawski, R., Webster, I.T., McArthur, M.A., Anderson, T.J., P.J. Siwabessy, Brooke, B. 2011. Including biogeochemical factors and a temporal component in benthic habitat maps: influences on infaunal diversity in a temperate embayment. Marine and Freshwater Research 62 (12): 1432 - 1448. Huang, Z., McArthur, M., Radke, L., Anderson, T., Nichol, S., Siwabessy, J. and Brooke, B. 2012. Developing physical surrogates for benthic biodiversity using co-located samples and regression tree models: a conceptual synthesis for a sandy temperature embayment. International Journal of Geographical Information Science DOI:10.1080/13658816.2012.658808.

This resource contains geochemistry data for the Oceanic Shoals Commonwealth Marine Reserve (CMR) in the Timor Sea collected by Geoscience Australia during September and October 2012 on RV Solander (survey GA0339/SOL5650). This dataset comprises inorganic element data from the fine fraction (Mud: <63um) of the upper ~2cm of seabed sediment. The Oceanic Shoals Commonwealth Marine Reserve survey was undertaken as an activity within the Australian Government's National Environmental Research Program Marine Biodiversity Hub and was the key component of Research Theme 4 - Regional Biodiversity Discovery to Support Marine Bioregional Plans. Hub partners involved in the survey included the Australian Institute of Marine Science, Geoscience Australia, the University of Western Australia, Museum Victoria and the Museum and Art Gallery of the Northern Territory. Data acquired during the survey included: multibeam sonar bathymetry and acoustic backscatter; sub-bottom acoustic profiles; physical samples of seabed sediments, infauna and epibenthic biota; towed underwater video and still camera observations of seabed habitats; baited video observations of demersal and pelagic fish, and; oceanographic measurements of the water column from CTD (conductivity, temperature, depth) casts and from deployment of sea surface drifters. Further information on the survey is available in the post-survey report published as Geoscience Australia Record 2013/38 (Nichol et al. 2013).

Geoscience Australia carried out marine surveys in Jervis Bay (NSW) in 2007, 2008 and 2009 (GA303, GA305, GA309, GA312) to map seabed bathymetry and characterise benthic environments through co-located sampling of surface sediments (for textural and biogeochemical analysis) and infauna, observation of benthic habitats using underwater towed video and stills photography, and measurement of ocean tides and wave-generated currents. Data and samples were acquired using the Defence Science & Technology Organisation (DSTO) Research Vessel Kimbla. Bathymetric mapping, sampling and tide/wave measurement were concentrated in a 3x5 km survey grid (named Darling Road Grid, DRG) within the southern part of the Jervis Bay, incorporating the bay entrance. Additional sampling and stills photography plus bathymetric mapping along transits was undertaken at representative habitat types outside the DRG. This 128 sample data set comprises major, minor and trace elements derived from x-ray fluorescence analysis of surface seabed sediments (~0-2 cm). Sediment surface area data are also presented. More Information: Radke, L.C., Huang, Z., Przeslawski, R., Webster, I.T., McArthur, M.A., Anderson, T.J., P.J. Siwabessy, Brooke, B. 2011. Including biogeochemical factors and a temporal component in benthic habitat maps: influences on infaunal diversity in a temperate embayment. Marine and Freshwater Research 62 (12): 1432 - 1448. Huang, Z., McArthur, M., Radke, L., Anderson, T., Nichol, S., Siwabessy, J. and Brooke, B. 2012. Developing physical surrogates for benthic biodiversity using co-located samples and regression tree models: a conceptual synthesis for a sandy temperature embayment. International Journal of Geographical Information Science DOI:10.1080/13658816.2012.658808.

The extent to which low-frequency sound from marine seismic surveys impacts marine fauna is a subject of growing concern. The predominant frequency range of seismic airgun emissions is within the hearing range of cetaceans, reptiles, and fishes, and it can also elicit a neurological response in some invertebrates. Offshore seismic surveys have long been considered to be disruptive to fisheries, but comparatively few studies target commercially important species in realistic exposure scenarios. One of the main challenges in underwater sound impact studies is the meaningful translation of laboratory results to the field. Underwater sound properties are affected by the sound source, as well as characteristics of the water column, substrate, and biological communities. The experimental set-up is also critical in determining accurate response measurements, and design features of holding tanks can lead to misinterpretation of results, particularly related to behaviour. It may be tempting to simplify laboratory results to show effect or no effect, where results should instead be interpreted in the context of realistic exposure scenarios and field conditions. This project was developed in response to concerns raised by the fishing industry during stakeholder consultation in the lead up to a proposed seismic survey in the Gippsland Basin (Victoria, Australia), in addition to a broader need to acquire baseline data that may be used to quantify potential impacts of seismic operations on marine organisms. The project involves seven experimental components conducted before, during and after the seismic survey in both control and experimental areas of the Gippsland Basin: 1) Theoretical noise modelling, 2) Field-based noise monitoring and modelling, 3) Image acquisition by Autonomous Underwater Vehicle (AUV), 4) Bivalve sampling by dredging, 5) Fish movement analysis by tagging, 6) Catch rate analysis, and 7) Environmental modelling during the 2010 mortality event. In this presentation, we describe these components and critically review our current understanding of low-frequency sound impact on marine fish and invertebrates.

The value of integrated high-resolution data sets in understanding the marine environment has been demonstrated in numerous studies around the Australian margin, however this approach has rarely been applied to studies in East Antarctica. This integrated approach was applied to a survey in Antarctica which utilised a multibeam sonar system, underwater video and sediment sampling to aid the understanding of seabed character and benthic biotopes in the coastal waters of the Vestfold Hills, near the Australian station of Davis. The Vestfold Hills is one of the largest ice-free areas on the East Antarctic coast. The coastal area is a complex of small islands, embayments and fjords. High-resolution bathymetry and backscatter data were collected over 42km2 to depths of 215 m. Epibenthic community data and in situ observations of seafloor morphology, substrate composition and bedforms were obtained from towed underwater video. The new high resolution datasets reveal a mosaic of rocky outcrops and sediment-filled basins. Analysis of the datasets was used to identify statistically distinct benthic assemblages and describe the physical habitat characteristics related to each assemblage, with seven discrete benthic biotopes identified. The biotopes include a range of habitat types including shallow coastal embayments and rocky outcrops, which are dominated by dense macroalgae communities, and deep muddy basins which are dominated by mixed invertebrate communities. Transition zones comprising steep slopes provide habitat for sessile invertebrate communities. Flat to gently sloping plains with a thin sandy cover on shallow bedrock are relatively barren. The relationship between benthic community composition and environmental parameters is complex with many variables (e.g. depth, substrate type, longitude, latitude and slope) contributing to differences in community composition. Depth and substrate type were identified as the main controls of benthic community composition, however, depth is likely a proxy for other unmeasured depth-dependent parameters such as light availability, frequency of disturbance by ice, currents and/or food availability. Sea ice cover is an important driver of benthic community composition, with dense macroalgae communities only found where ice-free conditions persist for most of the summer. The bathymetry data shows iceberg scouring is common, however, scouring does not appear to impact benthic community composition in the study area. This is the first study that has used an integrated sampling approach to investigate benthic assemblages across a range of habitats in a coastal marine environment in East Antarctica. This study demonstrates the efficacy of using multibeam and towed video systems to survey large areas of the seafloor in Antarctica where marine sampling is often logistically difficult, and to collect non-destructive high-resolution data in the sensitive Antarctic marine environment. The multibeam data provide a physical framework for understanding benthic habitats and the distribution of benthic communities. This research provides a baseline for assessing natural variability and human-induced change across the coastal marine environment (Australian Antarctic Science Project AAS-2201), contributes to Geoscience Australia's Marine Environmental Baseline Program, and supports Australian Government objectives to manage and protect the Antarctic marine environment.

Submarine canyons have been recognised as areas of significant ecological and conservation value for their enhanced primary productivity, benthic biomass and biodiversity. In Australia, 753 submarine canyons were mapped on all margins of the continent by the Marine Biodiversity Hub through the Australian Government's National Environmental Research Program. An analysis of canyon geomorphic metrics provided the basis to objectively classify these canyons across a hierarchy of physical characteristics (e.g. volume, depth range, rugosity) separately for shelf-incising and slope-confined canyons (Huang et al., 2014). Here we extend this analysis to include oceanographic variables in presenting a first pass assessment of habitat quality for all canyons on the Australian margin, with a focus on their upper reaches. This study is based on the premise that habitat heterogeneity, productivity and disturbance are the three factors that potentially determine the quality of a canyon habitat. For each factor we derived a range of variables to inform the assessment of habitat quality (see Table). Habitat heterogeneity was measured using a selection of eight geomorphic metrics including canyon volume and rugosity that are considered likely to have a positive relationship with habitat heterogeneity. Canyon productivity was assessed from five variables including: distance to the shelf break as a proxy of nutrient inputs from land and the continental shelf; bottom current speed as an indicator of nutrient supply to benthic epifauna (derived from time-series re-analysis of the BLUElink oceanographic model and in-situ data), and; measures of the probability, frequency and intensity of upwelling (also from BLUElink data). The BLUElink variables have positive relationships with productivity whereas the relationship between distance to shelf and productivity is negative. Benthic disturbance was assessed from the maximum and range of bottom current speeds, and the frequency and intensity of tropical cyclones. According to these relationships, individual canyons were assigned habitat quality scores, first separately for each variable and then aggregated for the three habitat factors. The final scores were obtained by averaging the scores of the three habitat factors. The results show that many submarine canyons on the eastern Australian margin have high habitat quality scores (see Figure). This is interpreted to be mainly due to the influence of the upwelling-favourable East Australian Current which generates high productivity throughout the year. The Albany canyons on the south-western margin also offer high habitat quality for marine species due to complex geometrical and geophysical structures. They also benefit from the upwelling-favourable Flinders Current. In contrast, canyons on the northern and western margins have lower habitat quality. Many of these canyons receive little input from land and continental shelf. In addition, the downwelling- favourable Leeuwin Current, which flows along the western margin of the continent, hampers the supply of deep water nutrients from reaching the upper reaches of canyons, particularly canyon heads that intersect the euphotic zone. Overall, these results provide a framework for targeted studies of canyons aimed at testing and verifying the habitat potential identified here and for establishing monitoring priorities for the ongoing management of canyon ecosystems.

Geoscience Australia is investigating the suitability of offshore sedimentary basins as potential CO2 storage sites. In May 2012 a seabed survey (GA0335/SOL5463) was undertaken in collaboration with the Australian Institute of Marine Science to acquire baseline marine data in the Petrel Sub-basin, Joseph Bonaparte Gulf. The aim was to collect information on possible connections (faults and fluid pathways) between the seabed and key basin units, and to characterise seabed habitats and biota. Two areas were surveyed (Area 1: 471 km2, depth ~ 80-100 m; Area 2: 181 km2, depth ~ 30-70 m), chosen to investigate the seabed over the potential supercritical CO2 boundary (Area 1) and the basin margin (Area 2), with Area 2 located around Flat Top 1 Well. Data analysed include multibeam sonar bathymetry and backscatter, seabed samples and their geochemical and biological properties, video footage and still images of seabed habitats and biota, and acoustic sub-bottom profiles. Pockmarks, providing evidence for fluid release, are present at the seabed, and are particularly numerous in Area 1. Area 1 is part of a sediment-starved, low-relief section of shelf characterised by seabed plains, relict estuarine paleochannels, and low-lying ridges. Facies analysis and radiocarbon dating of relict coastal plain sediment indicates Area 1 was a mangrove-rich environment around 15,500 years ago, transgressed near the end of the Last Glacial period (Meltwater Pulse 1A). Modern seabed habitats have developed on these relict geomorphic features, which have been little modified by recent seabed processes. Seabed habitats include areas of barren and bioturbated sediments, and mixed patches of sponges and octocorals on hardgrounds. In the sub-surface, stacked sequences of northwest-dipping to flat-lying, well-stratified sediments, variably incised by palaeochannels characterise the shallow geology of Area 1. Some shallow faulting through these deposits was noted, but direct linkages between seabed features and deep-seated faults were not observed. Area 2 is dominated by carbonate banks and ridges. Low-lying ridges, terraces and plains are commonly overlain by hummocky sediment of uncertain origin. Pockmarks are present on the margins of banks, and on and adjacent to ridges. Despite the co-location of banks and ridges with major faults at depth, there is a lack of direct evidence for structural connectivity, particularly because of significant acoustic masking in the sub-surface profiles of Area 2. While no direct structural relationship was observed in the acoustic sub-bottom profiles between these banks, ridges and faults visible in the basin seismic profiles, some faults extend through the upper basin units towards the seabed on the margin of Area 2. No evidence was detected at the seabed for the presence of thermogenic hydrocarbons or other fluids sourced from the basin, including beneath the CO2 supercritical boundary. The source of fluids driving pockmark formation in Area 1 is most likely decomposing mangrove-rich organic matter within late Pleistocene estuarine sediments. The gas generated is dominated by CO2. Additional fluids are potentially derived from sediment compaction and dewatering. Conceptual models derived from this are being used to inform regional-scale assessments of CO2 storage prospectivity in the Petrel Sub-basin.

Seabed mapping studies are supporting the regulation and management of a range of competing industries in northern Australia. These industries include fishing and an expanding offshore energy sector, with new developments to include seabed pipelines and subsurface storage of CO2. Set in tropical waters, the northern Australian shelf is also recognised in marine management plans for its high-value marine biodiversity associated with a complex geomorphology. To reduce uncertainty and risk in the future development and management of this region, the Australian Government is supporting seabed mapping research under a series of programs aimed at delivering integrated information relevant to infrastructure development (Offshore Energy Security Program, 2007-2010), offshore storage of CO2 in deep sedimentary basins (National CO2 Infrastructure Program, 2011-2015) and biodiversity conservation of the marine estate (National Environmental Research Program, 2011-2014). In 2009 and 2010, Geoscience Australia undertook collaborative seabed mapping surveys to deliver to these programs, with an initial focus on the eastern Joseph Bonaparte Gulf (Timor Sea). Objectives were to: characterise the physical and biological properties of the seabed in representative areas; assess potential geohazards, and; identify unique or sensitive benthic habitats.