The northern Australian continental shelf is the focus for an expanding offshore energy industry and is also recognised for its high-value marine biodiversity in regional marine management plans. To reduce uncertainty and risk in the future development and management of the region, Geoscience Australia has an ongoing program to provide integrated marine environmental information to support both activities. The program includes collation of existing marine data and acquisition of new high resolution datasets. In 2009 and 2010, marine surveys in eastern Joseph Bonaparte Gulf were completed to characterise the seabed in representative areas, assess potential for geohazards and identify unique or sensitive benthic habitats. Data acquired included multibeam sonar bathymetry (~1900 km2), shallow (<120 m) sub-bottom profiles, sediment grabs and shallow (2-5 m) cores, towed video and epibenthic sleds. Geomorphic features mapped range from expansive soft-sediment plains, to isolated carbonate banks that rise tens of metres and incised valleys up to 200 m deep. Each feature is characterised by a distinctive biota, ranging from coral and sponge gardens on banks to diverse infaunal communities across plains. Geohazards include potential for localised slumping in valleys and escape of subsurface fluid/gas from plains and valley floors. To facilitate uptake of this information, results are integrated as generalised graphical models representing key spatial patterns of shelf ecosystems. This work has led to further work in targeted areas of the Gulf as part of a new four-year Australian Government program to inform geological and environmental assessments of offshore basins for CO2 storage.

Cool-water carbonate environments may be responsible for up to one third of the carbonate sediment produced on continental shelves, and are useful modern analogues for many geologically ancient deposits. The extensive southern margin of the Australian continent is recognised as the world's largest modern example of a high energy, cool-water carbonate depositional realm. A number of studies have suggested that Quaternary sediment production here is largely influenced by oceanography, and that wave abrasion strongly limits sediment accumulation. Therefore, in this region the outer-shelf, below the storm wave base, is thought to be the focus of sediment accumulation. The inner shelf is considered a zone of active sediment production due to the proliferation of carbonate secreting organisms, although few studies have investigated sediment production or accumulation in this energetic and dynamic environment. The Recherche Archipelago, which sits at the western margin of the Great Australian Bight (GAB), was examined to better understand Quaternary shelf evolution and the importance of this type of inner shelf as a carbonate 'factory'. Surficial sediments, video, multibeam sonar data, cores and shallow seismics were collected. The present seabed of the archipelago features extensive areas where flat-lying limestones sit over the often irregular granite basement. The Pleistocene erosional surface is overlain by a coarse bivalve and rhodolith dominated gravel lag. Significantly, there are extensive Holocene deposits, up to 7 m thick, throughout the archipelago, particularly in association with granite islands. These deposits comprise cross-bedded gravelly carbonate sands dominated by fragments of calcareous algae (rhodoliths), molluscs and bryozoans. In contrast, the inshore and coast is dominated by terrigenous sediment. Seismic profiles and preserved palaeo-shoreline features suggest that slow but episodic aggradation of marine sediment has occurred on the inner shelf over successive Quaternary sea level cycles, although there are also extensive areas of non-deposition. This accumulation is partly attributable to the sheltering effect of high-relief granitic outcrops and cementation of subaerially exposed carbonate sediments.

This dataset contains species identifications of macro-benthic worms collected during survey GA2476 (R.V. Solander, 12 August - 15 September 2008). Animals were collected from the Western Australian Margin with a BODO sediment grab or rock dredge. Specimens were lodged at Museum of Victoria on the 10 March 2009. Species-level identifications were undertaken by Robin Wilson at the Museum of Victoria and were delivered to Geoscience Australia on the 7 May 2009. See GA Record 2009/02 for further details on survey methods and specimen acquisition. Data is presented here exactly as delivered by the taxonomist, and Geoscience Australia is unable to verify the accuracy of the taxonomic identifications.

Much of the deep sea encompasses soft-sediment plains, with very few hard substrates for invertebrates to colonise. At first glance, these habitats seem barren, but they are actually teeming with life. Compared to organisms from shallow water, many animals here are quite small. In addition, most of the animals are infaunal, meaning they live within the sediment. During feeding and burrowing, these animals form a range of features called lebensspuren, defined as any type of sedimentary structure produced by a living organism. Sampling deep sea animals can be a challenge, and traditional methods of grabs and boxcores provide only a single snapshot of a small area to characterise broad regions. Underwater imagery facilitates the characterisation of biological communities over a larger area, but the quantification of biodiversity from video is often restricted to larger epifauna, thus reducing its utility to measure biodiversity in deep sea soft sediments where animals are often small or infaunal. High resolution still images provide an interesting avenue with which to quantify biological activity based on lebensspuren. In this study, we used thousands of still images taken along the edge of the Eastern and Western margins of Australia to identify and characterise deep-sea lebensppuren. The features identified were compiled into a Lebensspuren Directory (Section 7), and the data was used to correlate abiotic factors to lebensspuren and to valuate whether the quantification of lebensspuren from still photographs is an appropriate technique for broadly quantifying biological activity and diversity in the deep sea (Sections 2 - 6).

Processes across the grounding zone are important in understanding the retreat behaviour of ice streams but are poorly understood because of the difficulty of accessing the region. The Antarctic Shelf preserves geomorphic features and sedimentary structures left by ice retreat which can provide insights into processes in and close to the grounding zone. Sidescan sonar records from Prydz Bay image a range of features that reflect changes in processes across the Amery Ice Shelf grounding zone during retreat after the Last Glacial Maximum. The presence of fluted and mega-scale glacial lineations indicates that the ice moved over an unfrozen, deforming bed in the zone up stream of the grounding zone. For most of the Amery Ice Shelf, the inter-flute dunes reflect strong thermohaline circulation in the ice shelf cavity. Sand and gravel recovered in cores from beneath the Amery Ice Shelf indicate significant current speeds, possibly enhanced by tidal pumping. The sea floor in the Lambert Deep on the western edge of the Amery Ice Shelf lacks inter-flute dunes and has a sea floor covered in subglacial features. Transverse steps cutting across flutes indicate the presence of subglacial cavities at the bed between patches of grounded ice as the ice approached the grounding zone. The presence of an esker indicates water flowing in a subglacial tunnel. The polygonal ridges are similar to those formed where surging glaciers have stagnated. This at least implies periods of stagnation before the ice flowing into the Lambert Deep retreated from successive grounding line positions.

Geoscience Australia undertook a marine survey of the Leveque Shelf (survey number SOL5754/GA0340), a sub-basin of the Browse Basin, in May 2013. This survey provides seabed and shallow geological information to support an assessment of the CO2 storage potential of the Browse sedimentary basin. The basin, located on the Northwest Shelf, Western Australia, was previously identified by the Carbon Storage Taskforce (2009) as potentially suitable for CO2 storage. 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 principal aim of the Leveque Shelf marine survey was to look for evidence of any past or current gas or fluid seepage at the seabed, and to determine whether these features are related to structures (e.g. faults) in the Leveque Shelf area that may extend to the seabed. The survey also mapped seabed habitats and biota to provide information on communities and biophysical features that may be associated with seepage. This research, combined with deeper geological studies undertaken concurrently, addresses key questions on the potential for containment of CO2 in the basin's proposed CO2 storage unit, i.e. the basal sedimentary section (Late Jurassic and Early Cretaceous), and the regional integrity of the Jamieson Formation (the seal unit overlying the main reservoir). This dataset comprises total chlorin concentrations and chlorin indices from the upper 2cm of seabed sediments.

Geoscience Australia undertook a marine survey of the Leveque Shelf (survey number SOL5754/GA0340), a sub-basin of the Browse Basin, in May 2013. This survey provides seabed and shallow geological information to support an assessment of the CO2 storage potential of the Browse sedimentary basin. The basin, located on the Northwest Shelf, Western Australia, was previously identified by the Carbon Storage Taskforce (2009) as potentially suitable for CO2 storage. 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 principal aim of the Leveque Shelf marine survey was to look for evidence of any past or current gas or fluid seepage at the seabed, and to determine whether these features are related to structures (e.g. faults) in the Leveque Shelf area that may extend to the seabed. The survey also mapped seabed habitats and biota to provide information on communities and biophysical features that may be associated with seepage. This research, combined with deeper geological studies undertaken concurrently, addresses key questions on the potential for containment of CO2 in the basin's proposed CO2 storage unit, i.e. the basal sedimentary section (Late Jurassic and Early Cretaceous), and the regional integrity of the Jamieson Formation (the seal unit overlying the main reservoir). This dataset comprises total chlorin concentrations and chlorin indices from the upper 2cm of seabed sediments.

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 total sediment metabolism, bulk carbonate and mineral specific surface area measurements, and major and minor trace elements and carbon and nitrogen concentrations and isotopes in the upper 2 cm of seabed sediments.

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 chlorin concentrations and chlorin indices measured on 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

The Rowley Shoals/Offshore Canning and Roebuck basins survey was conducted on the RV Southern Surveyor survey SS06/2006 (GA-2408) between the 29th May and 22 June 2006. The primary aim of the survey was to identify any sites of natural hydrocarbon seepage, that may provide direct evidence for an active petroleum system within the sub‐surface. A secondary objective was to contribute to the understanding of the modern sedimentary and oceanographic processes influencing this part of the shelf, and to assess the nature of the benthic habitats. Underwater video was captured at 12 sites, with a minimum of 10 minutes to 60 minutes at each site, which totalled approximately 5.5 hours of footage. Video was recorded to mini DV tapes and copied to digital format. Descriptions of footage acquired during the underwater video tows are provided in the post-survey report (GA Record 2007/21 - Geocat # 65453). Please note that the underwater video is unclipped, contains descent and ascent through the water column, laser points in the video are reported to be spaced at 25 cm, and start locations of the underwater video camera stations are found in the Post-survey report.