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  • Geoscience Australia (GA) conducted a marine survey (GA0345/GA0346/TAN1411) of the north-eastern Browse Basin (Caswell Sub-basin) between 9 October and 9 November 2014 to acquire seabed and shallow geological information to support an assessment of the CO2 storage potential of the basin. The survey, undertaken as part of the Department of Industry and Science's National CO2 Infrastructure Plan (NCIP), aimed to identify and characterise indicators of natural hydrocarbon or fluid seepage that may indicate compromised seal integrity in the region. The survey was conducted in three legs aboard the New Zealand research vessel RV Tangaroa, and included scientists and technical staff from GA, the NZ National Institute of Water and Atmospheric Research Ltd. (NIWA) and Fugro Survey Pty Ltd. Shipboard data (survey ID GA0345) collected included multibeam sonar bathymetry and backscatter over 12 areas (A1, A2, A3, A4, A6b, A7, A8, B1, C1, C2b, F1, M1) totalling 455 km2 in water depths ranging from 90 - 430 m, and 611 km of sub-bottom profile lines. Seabed samples were collected from 48 stations and included 99 Smith-McIntyre grabs and 41 piston cores. An Autonomous Underwater Vehicle (AUV) (survey ID GA0346) collected higher-resolution multibeam sonar bathymetry and backscatter data, totalling 7.7 km2, along with 71 line km of side scan sonar, underwater camera and sub-bottom profile data. Twenty two Remotely Operated Vehicle (ROV) missions collected 31 hours of underwater video, 657 still images, eight grabs and one core. This catalogue entry refers to the sub-bottom profiler data acquired by the Fugro supplied AUV system (survey GA-0346).

  • In May 2013, Geoscience Australia (GA) and the Australian Institute of Marine Science (AIMS) undertook a collaborative seabed mapping survey (GA0340/ SOL5754) on the Leveque Shelf, a distinct geological province within the Browse Basin, offshore Western Australia. The purpose of the survey was to acquire geophysical and biophysical data on seabed environments over a previously identified potential CO2 injection site to better understand the overlying seabed habitats and to assess potential for fluid migration to the seabed. Mapping and sampling was undertaken across six areas using multibeam and single beam echosounders, sub-bottom profilers, sidescan sonar, underwater towed-video, gas sensors, water column profiler, grab samplers, and vibrocorer. Over 1070 km2 of seabed and water column was mapped using the multibeam and single beam echosounder, in water depths ranging between 40 and 120 m. The sub-surface was investigated using the multichannel and the parametric sub-bottom profilers along lines totalling 730 km and 1547 km in length respectively. Specific seabed features were investigated over 44 line km using the sidescan sonar and physically and sampled at 58 stations. Integration of this newly acquired data with existing seismic data will provide new insights into the geology of the Leveque Shelf. This work will contribute to the Australian Government's National CO2 Infrastructure Plan (NCIP) by providing key seabed environmental and geological data to better inform the assessment of the CO2 storage potential in this area of the Browse Basin. This catalogue entry refers to an interpreted geomorphic map, mapped at 1:10 000 scale. Geomorphic mapping was completed using a combination of semi-automated feature extraction and hand digitisation from bathymetry and backscatter grids collected during the survey along with their derivatives and reference to broader scale geomorphic maps (Heap and Harris, 2008).

  • This report presents the results of seabed mapping and habitat classification surveys completed in Darwin Harbour during 2011 and 2013 as part of the Northern Territory Government's marine habitat mapping program. This research aims to provide baseline data on the existing marine habitats and characteristics of the Darwin Harbour region. It is a collaboration between Geoscience Australia (GA), the Australian Institute of Marine Science (AIMS), the Department of Land Resource Management (DLRM) and the Darwin Port Corporation. Key objectives are to: - Produce detailed maps of the bathymetry and derived parameters such as slope and rugosity, - Classify the seabed into areas of hard and soft substrate, and, - Produce seabed habitat maps (or seascapes). Data collection was completed in two stages comprising a multibeam survey, undertaken on the MV Matthew Flinders in 2011 by DLRMs predecessor, the Department of Natural Resources, Environment, the Arts and Sport (NRETAS), GA, AIMS and the Darwin Port Corporation; and, a seabed sampling survey undertaken in 2013 on the MV John Hickman, by DLRM and GA. Data acquired from the surveys included continuous high-resolution multibeam sonar bathymetry and acoustic backscatter, video and still camera observations of seabed habitats and biological communities, and physical samples of seabed sediments. Key outcomes from the surveys include: 1. Improved understanding of the seabed of Darwin Harbour. The main seabed geomorphic features identified in Darwin Harbour include banks, ridges, plains and scarps, and a deep central channel that divides into smaller and shallower channels. Acoustically hard substrates are found mostly on banks and are associated with rocky reef and sponge gardens, and are often overlain by a thin veneer of sandy sediment. In contrast, plains and channels are characterised by acoustically soft substrates and are associated with fine sediments (mud and sand). 2. Classification of physical seabed properties to produce a Seascape Map for Darwin Harbour. Six seascape classes (potential habitats) were derived using an Iterative Self Organising (ISO) unsupervised classification scheme. These six classes are related to statistically unique combinations of seabed substrate, relief, bedform and presence of sediment veneer (quite often inferred from presence of epibenthic biota). The results presented in this report demonstrate the utility of multibeam acoustic data to broadly and objectively characterise the seabed to describe the spatial distribution of key benthic habitats. This is particularly important technique in high-turbidity settings such as Darwin Harbour where the application of satellite and aerial remote sensing techniques can be limited. The results of this study will be used for the planning and analysis of data from upcoming benthic biodiversity studies as they: - Provide robust near-continuous physical variables that can be used to predictive modelling of biodiversity; - Provide high-resolution coverage of near-continuous variables that describe the key physical characteristic of the seabed of the harbour, and; - Enhance survey sample design by providing indicative locations of likely similar biology communities.

  • The Petrel Sub-basin Marine Environmental Survey GA-0335, (SOL5463) was undertaken by the RV Solander during May 2012 as part of the Commonwealth Government's National Low Emission Coal Initiative (NLECI). The survey was undertaken as a collaboration between the Australian Institute of Marine Science (AIMS) and GA. The purpose was to acquire geophysical and biophysical data on shallow (less then 100m water depth) seabed environments within two targeted areas in the Petrel Sub-basin to support investigation for CO2 storage potential in these areas. This dataset comprises TCO2 pools (0-2cm) and fluxes calculated from bottle incubation experiments (24 hours).

  • This dataset contains sediment and geochemistry information 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). Further information on the survey is available in 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).

  • Geoscience Australia marine reconnaissance survey GA2476 to the west Australian continental margin was undertaken as part of the Australian Government's Offshore Energy Program between 25 October 2008 and 19 January 2009 using the German research vessel RV Sonne. The survey acquired geological, geophysical, oceanographic and biological data over poorly known areas of Australia's western continental margin in order to improve knowledge of frontier sedimentary basins and marginal plateaus, and allow assessment of their petroleum prospectivity and environmental significance. Four key areas were targeted: the Zeewyck and Houtman sub-basins (Perth Basin), the Cuvier margin (northwest of the Southern Carnarvon Basin), and the Cuvier Plateau (a sub-feature of the Wallaby Plateau). These areas were mapped using multi-beam sonar, shallow seismic, magnetics and gravity. Over the duration of the survey a total of 229,000 km2 (26,500 line-km) of seabed was mapped with the multibeam sonar, 25,000 line-km of digital shallow seismic reflection data and 25,000 line-km of gravity and magnetic data. Sampling sites covering a range of seabed features were identified from the preliminary analysis of the multi-beam bathymetry grids and pre-existing geophysical data (seismic and gravity). A variety of sampling equipment was deployed over the duration of the survey, including ocean floor observation systems (OFOS), deep-sea TV controlled grab (BODO), boxcores, rock dredges, conductivity-temperature depth profilers (CTD), and epibenthic sleds. Different combinations of equipment were used at each station depending on the morphology of the seabed and objectives of each site. A total of 62 stations were examined throughout the survey, including 16 over the Houtman Sub-basin, 16 over the Zeewyck Subbasin, 13 in the Cuvier margin, 12 over the Cuvier Plateau and four in the Indian Ocean. This dataset comprises total sediment metabolism (measured as dissolved inorganic carbon (DIC) fluxes) from the upper 2 cm of seabed sediments. For more information: Daniell, J., Jorgensen, D.C., Anderson, T., Borissova, I., Burq, S., Heap, A.D., Hughes, M., Mantle, D., Nelson, G., Nichol, S., Nicholson, C., Payne, D., Przeslawski, R., Radke, L., Siwabessy, J., Smith, C., and Shipboard Party, (2010). Frontier Basins of the West Australian Continental Margin: Post-survey Report of Marine Reconnaissance and Geological Sampling Survey GA2476. Geoscience Australia, Record 2009/38, 229pp

  • Geoscience Australia (GA) conducted a marine survey (GA0345/GA0346/TAN1411) of the north-eastern Browse Basin (Caswell Sub-basin) between 9 October and 9 November 2014 to acquire seabed and shallow geological information to support an assessment of the CO2 storage potential of the basin. The survey, undertaken as part of the Department of Industry and Science's National CO2 Infrastructure Plan (NCIP), aimed to identify and characterise indicators of natural hydrocarbon or fluid seepage that may indicate compromised seal integrity in the region. The survey was conducted in three legs aboard the New Zealand research vessel RV Tangaroa, and included scientists and technical staff from GA, the NZ National Institute of Water and Atmospheric Research Ltd. (NIWA) and Fugro Survey Pty Ltd. Shipboard data (survey ID GA0345) collected included multibeam sonar bathymetry and backscatter over 12 areas (A1, A2, A3, A4, A6b, A7, A8, B1, C1, C2b, F1, M1) totalling 455 km2 in water depths ranging from 90 - 430 m, and 611 km of sub-bottom profile lines. Seabed samples were collected from 48 stations and included 99 Smith-McIntyre grabs and 41 piston cores. An Autonomous Underwater Vehicle (AUV) (survey ID GA0346) collected higher-resolution multibeam sonar bathymetry and backscatter data, totalling 7.7 km2, along with 71 line km of side scan sonar, underwater camera and sub-bottom profile data. Twenty two Remotely Operated Vehicle (ROV) missions collected 31 hours of underwater video, 657 still images, eight grabs and one core. This catalogue entry refers to chlorophyll a, b, c and phaeophytin a conentrations in the upper 2 cm of seabed sediments.

  • Marine organisms are exposed not only to natural environmental stressors, but also the additional effects of anthropogenic stressors, notably increasing temperatures and reduced pH. Early life stages of marine organisms have been recognised as potentially vulnerable to the stressors associated with climate change and ocean acidification, but identifying patterns across studies, species and a range of response variables is challenging. This study is supported by the Marine Biodiversity Hub through the National Environmental Research Program and identifies knowledge gaps in research on multiple abiotic stressors and early life stage (embryo to larvae), while quantifying interactions based on life history. Temperature was the most common stressor (91% of studies), while the most common combination of stressors was temperature and salinity (66%), followed by temperature and pH (17.5%). All studies were conducted in the laboratory although four studies also undertook field experiments. Synergistic interactions (68% of individual tests) were more common than additive (16%) or antagonistic (16%) interactions. The meta-analysis yielded several key results: 1) Embryos are not more vulnerable to stress than larvae in combined stressor treatments. 2) Sub-lethal responses are not more likely to be affected by stress than lethal responses. 3) Interaction types vary among stressors, phyla, ontogenetic stages, and biological responses. 4) Elevated temperature is generally a greater stressor than ocean acidification, but this depends on ontogenetic stage and phylum. 5) Ocean acidification is a greater stressor for calcifying than non-calcifying larvae. Our findings will assist in monitoring and predicting the health of marine populations and communities by identifying sensitive and robust taxa.

  • Geoscience Australia undertook a marine survey of the Vlaming Sub-basin in March and April 2012 to provide seabed and shallow geological information to support an assessment of the CO2 storage potential of this sedimentary basin. The survey was undertaken under the Australian Government's National CO2 Infrastructure Plan (NCIP) to help identify sites suitable for the long term storage of CO2 within reasonable distances of major sources of CO2 emissions. The Vlaming Sub-basin is located offshore from Perth, Western Australia, and was previously identified by the Carbon Storage Taskforce (2009) as potentially suitable for CO2 storage. The principal aim of the Vlaming Sub-basin marine survey (GA survey number GA0334) was to look for evidence of fault reactivation and of any past or current gas or fluid seepage at the seabed. The survey also mapped seabed habitats and biota in the areas of interest to provide information on communities and biophysical features that may be associated with seepage. This data package brings together the following datasets which describe biophysical aspects of seafloor sediments: GEOCAT#74276. Underwater video footage from the Vlaming Sub-basin (GA0334). GEOCAT#76463. GA0334 Vlaming sub-basin Species identification of worms from grab. GEOCAT#78540. Vlaming Sub-Basin Marine Environmental Survey (GA-0334/S. Supporter GP 1373) (NCIP Program) - High Resolution Bathymetry grids. GEOCAT# 78550. Seabed environments and shallow geology of the Vlaming sub-basin, Western Australia: Chlorin analyses of seabed sediments. GEOCAT#78551. Seabed environments and shallow geology of the Vlaming sub-basin, Western Australia: Inorganic elements of seabed sediments. GEOCAT#78552. Seabed environments and shallow geology of the Vlaming sub-basin, Western Australia: Bulk organic carbon and nitrogen isotopes and concentrations in seabed sediments. GEOCAT#78553. Seabed environments and shallow geology of the Vlaming sub-basin, Western Australia: Sediment oxygen demand of seabed sediments. GEOCAT#78564. Seabed environments and shallow geology of the Vlaming sub-basin, Western Australia: Chlorophyll a, b and c of seabed sediments. GEOCAT#78565. Seabed environments and shallow geology of the Vlaming sub-basin, Western Australia: %carbonate and specific surface area of seabed sediments. GEOCAT#79176. Seabed environments and shallow geology of the Vlaming sub-basin, Western Australia: Grain size and carbonate concentrations of seabed sediments. GEOCAT#79345. Ecology / Infaunal morphospecies identifications from the Vlaming Sub-basin (GA0334). An account of the field operations is published in: GEOCAT 74626. Nicholas, W. A., Borissova, I., Radke, L., Tran, M., Bernardel, G., Jorgensen, D M., Siwabessy, J., Carroll, A. and Whiteway, T., 2012. Seabed Environments and Shallow Geology of the Vlaming Sub-Basin, Western Australia - Marine data for the Investigation of the Geological Storage of CO2. GA0334 Post-Survey Report. Geoscience Australia, Record 2013/09. A preliminary interpretation of seabed data is provided in: GEOCAT 78846. Nicholas, W. A., Howard, F., Carroll, A., Siwabessy, J., Tran, M., Picard, K., Przeslawski, R. and Radke, L. 2014. Seabed Environments and shallow sub-surface geology of the Vlaming Sub-basin, offshore Perth Basin: summary report on observed and potential seepage, and habitats. Geoscience Australia, Record 2014/XXX. Information on the broader study, evaluating the Vlaming Sub-basin CO2 storage potential and providing details of the suitable storage sites, is available in: GEOCAT 79332. Borissova, I, Lech, M.E., Jorgensen, D.C, Southby, C., Wang, L., Bernardel, G., Nicholas, T., Lescinsky, D.L. and Johnston, S. An integrated study of the CO2 storage potential in the offshore Vlaming Sub-basin. Geoscience Australia, Record 2014/XXX.

  • Geoscience Australia (GA) conducted a marine survey (GA0345/GA0346/TAN1411) of the north-eastern Browse Basin (Caswell Sub-basin) between 9 October and 9 November 2014 to acquire seabed and shallow geological information to support an assessment of the CO2 storage potential of the basin. The survey, undertaken as part of the Department of Industry and Science's National CO2 Infrastructure Plan (NCIP), aimed to identify and characterise indicators of natural hydrocarbon or fluid seepage that may indicate compromised seal integrity in the region. The survey was conducted in three legs aboard the New Zealand research vessel RV Tangaroa, and included scientists and technical staff from GA, the NZ National Institute of Water and Atmospheric Research Ltd. (NIWA) and Fugro Survey Pty Ltd. Shipboard data (survey ID GA0345) collected included multibeam sonar bathymetry and backscatter over 12 areas (A1, A2, A3, A4, A6b, A7, A8, B1, C1, C2b, F1, M1) totalling 455 km2 in water depths ranging from 90 - 430 m, and 611 km of sub-bottom profile lines. Seabed samples were collected from 48 stations and included 99 Smith-McIntyre grabs and 41 piston cores. An Autonomous Underwater Vehicle (AUV) (survey ID GA0346) collected higher-resolution multibeam sonar bathymetry and backscatter data, totalling 7.7 km2, along with 71 line km of side scan sonar, underwater camera and sub-bottom profile data. Twenty two Remotely Operated Vehicle (ROV) missions collected 31 hours of underwater video, 657 still images, eight grabs and one core. This catalogue entry refers to the ship-based Sub-Bottom Profiler (SBP) SEGY-format line data (ie survey GA-0345) acquired within the survey areas.