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  • The deep waters within the Gascoyne Marine Park have been largely unexplored for their seafloor biodiversity. Survey FK200308 on the RV Falkor targeted two canyons within the Gascoyne Marine Park to understand and map the distribution and diversity of marine habitats and biota within the Cape Range and Cloates Canyons. These canyons were targeted to better understand their ecological significance as a conduit between shelf environments adjacent to the Ningaloo Reef and the abyssal plain. They occur within the habitat protection and multiple use zones of the Gascoyne Marine Park off north-western Australia. Survey FK200308 was led by researchers at the Western Australian Museum, and included scientists from Geoscience Australia, Curtin University, Macquarie University and Scripps Institute of Oceanography. Multibeam sonar was used to map parts of the marine park, while a Remotely Operated Vehicle (ROV) was deployed to undertake a comprehensive taxon inventory of the North-West canyon fauna based on underwater imagery and sampling. Additional biological samples were collected via plankton sampling, as well as fish and crustacean traps on a lander, and stand-alone fish trap deployments. Autonomous Reef Monitoring Structures (ARMS) were deployed at select sites to capture cryptic benthic organisms over several years. DNA samples from the water column (eDNA) were collected to enable a broader understanding of the biodiversity of the region, and to provide a methodological comparison to the organisms present at the time of sampling. The key drivers for this survey were to collect Information to enhance our understanding of the Gascoyne Marine Park and deep-sea environments throughout Western Australia, and to facilitate comparisons between the north-west and eastern and southern Australian deep-sea waters. This information can be applied to inform management plans, scientific research and industry activities for the North-West. Specifically, this survey provided: • A faunal inventory as a baseline information for monitoring deep water WA environments. A total of 2570 seafloor images were annotated from quantitative transects, more than 1000 specimens were collected and up to 30 new species discovered. • High resolution mapping of the seafloor across an area of 11,250 km2 revealed a detailed understanding of seabed habitats and environments in the Gascoyne Marine Park, and a regional context in which to interpret the faunal inventory. • Repeat multibeam mapping of the Cape Range and Cloates Canyons informed our understanding of seabed stability in the canyons of the Gascoyne Marine park, illustrating a rare case of true monitoring using multibeam in Australian waters. • The use of a state-of-the-art ROV across 20 deployments helped inform a new ROV field manual (Monk et al. 2020), adding to the existing suite of standard operating procedures supported by Parks Australia (https://marine-sampling-field-manual.github.io/). This survey confirmed that canyons within the Gascoyne Marine Park are important ecological systems, supporting numerous deep-sea species, many of which were discovered to be new to science. The advanced capabilities of the ROV SuBastian to navigate and image complex near vertical walls and overhangs within the canyons revealed patterns in the distribution of the seafloor taxa consistent with small-scale environmental variability. Repeat multibeam mapping revealed a dynamic canyon system that continues to be shaped by turbidity events. The occurrence of reworked seagrass blades within the canyons provided new understanding of these canyon systems as an active conduit between shallow shelf and abyssal environments. The distribution of the seabed biota revealed through quantitative ROV transects emphasised the importance of disturbance patterns in shaping the canyon ecosystems.

  • Here we present the surficial geology map for the Vestfold Hills, East Antarctica. On the coast of Prydz Bay, the region is one of the largest ice-free areas in Antarctica. Surficial geology mapping at 1:2000 was undertaken with field observations in the 2018/19 and 2019/20 summer seasons as well as aerial photography and satellite imagery interpretation. Units are based on the Geological Survey of Canada Surficial Data Model Version 2.4.0 (Deblonde et al 2019).

  • This unique, interactive map shows how crowdsourced photographs can help to highlight some of Australia's great geological features. The interactive map, built using the ESRI Storymap functionality, combines geolocation information with superb imagery gathered by amateur and professional photographers. The map features the best 68 images selected from over 300 entries in the 2015 Top GeoShot photographic competition.

  • This report presents key results from hydrogeological investigations in the Tennant Creek region, completed as part of Exploring for the Future (EFTF)—an eight year, $225 million Australian Government funded geoscience data and information acquisition program focused on better understanding the potential mineral, energy and groundwater resources across Australia. The EFTF Southern Stuart Corridor (SSC) Project area is located in the Northern Territory and extends in a north–south corridor from Tennant Creek to Alice Springs, encompassing four water control districts and a number of remote communities. Water allocation planning and agricultural expansion in the SSC is limited by a paucity of data and information regarding the volume and extent of groundwater resources and groundwater systems more generally. Geoscience Australia, in partnership with the Northern Territory Department of Environment and Natural Resources and Power and Water Corporation, undertook an extensive program of hydrogeological investigations in the SSC Project area between 2017 and 2019. Data acquisition included; helicopter airborne electromagnetic (AEM) and magnetic data; water bore drilling; ground-based and downhole geophysical data for mapping water content and defining geological formations; hydrochemistry for characterising groundwater systems; and landscape assessment to identify potential managed aquifer recharge (MAR) targets. This report focuses on the Tennant Creek region—part of the Barkly region of the Northern Territory. Investigations in this region utilised existing geological and geophysical data and information, which were applied in the interpretation and integration of AEM and ground-based geophysical data, as well as existing and newly acquired groundwater hydrochemical and isotope data. The AEM and borehole lithological data reveal the highly weathered (decomposed) nature of the geology, which is reflected in the hydrochemistry. These data offer revised parameters, such as lower bulk electrical conductivity values and increased potential aquifer volumes, for improved modelling of local groundwater systems. In many instances the groundwater is shown to be young and of relatively good quality (salinity generally <1000 mg/L total dissolved solids), with evidence that parts of the system are rapidly recharged by large rainfall events. The exception to this is in the Wiso Basin to the west of Tennant Creek. Here lower quality groundwater occurs extensively in the upper 100 m below ground level, but this may sit above potentially potable groundwater and that possibility should be investigated further. Faults are demonstrated to have significantly influenced the occurrence and distribution of weathered rocks and of groundwater, with implications for groundwater storage and movement. Previously unrecognised faults in the existing borefield areas should be investigated for their potential role in compartmentalising groundwater. Additionally a previously unrecognised sub-basin proximal to Tennant Creek may have potential as a groundwater resource or a target for MAR. This study has improved understanding of the quantity and character of existing groundwater resources in the region and identified a managed aquifer recharge target and potential new groundwater resources. The outcomes of the study support informed water management decisions and improved water security for communities; providing a basis for future economic investment and protection of environmental and cultural values in the Tennant Creek and broader Barkly region. Data and information related to the project are summarised in the conclusions of this report and are accessible via the EFTF portal (https://portal.ga.gov.au/).

  • This flythrough shows the seafloor bathymetry, cores and canyon names for the Sabrina slope region of East Antarctica. Indigenous names for canyons were proposed following consultation with the Noongar people in Western Australia, the region of Western Australia that was formerly conjugate to the Sabrina margin. Canyon names are as follows: 1. Boongorang Canyon (Blowing in the wind) 2. Manang Canyon (Pool of Water Canyon) 3. Maadjit Canyon (Water Serpent Canyon) 4. Jeffrey Canyon (after Shirley Jeffrey, diatom researcher) 5. Morka Canyon (Winter Canyon) 6. Minang-a Canyon (Whale Canyon)

  • The East Antarctic slope on the Sabrina margin has been shaped by diverse processes related to repeated glaciation. Differences in slope along this margin have driven variations in sedimentation that explain the gully morphology. Areas of lower slope angles have led to rapid sediment deposition during glacial expansion to the shelf edge, and subsequent sediment failure. Gullies in these areas are typically extremely U-shaped, initiate well below the shelf break, are relatively straight and long, and have low incision depths. Areas of higher slope angles enhance the flow of erosive turbidity currents during glaciations associated with the release of sediment-laden basal meltwaters. The meltwater flows create gullies that typically initiate at or near the shelf break, are V-shaped in profiles, have high sinuosity, deep incision depths and a relatively short down slope extent. The short down slope extent reflects a reduced sediment load associated with increased seawater entrainment as the slope becomes more concave in profile. These differences in gully morphology have important habitat implications, associated with differences in the structure and beta-diversity of the seafloor communities. This upper slope region also supports seafloor communities that are distinct from those on the adjacent shelf, highlighting the uniqueness of this environment for biodiversity. <b>Citation:</b> A.L. Post, P.E. O'Brien, S. Edwards, A.G. Carroll, K. Malakoff, L.K. Armand, Upper slope processes and seafloor ecosystems on the Sabrina continental slope, East Antarctica, <i>Marine Geology</i>, Volume 422, 2020, 106091, ISSN 0025-3227, https://doi.org/10.1016/j.margeo.2019.106091.

  • Repeat multibeam mapping of two slope-confined canyons on the northwest Australian margin provides new understanding of the processes that are active in shaping these environments. The Cape Range and Cloates Canyons initiate on the mid- to lower continental slope, but are connected to the shelf via small channels and gullies. These canyons were first mapped systematically with multibeam sonar in 2008 and were remapped in 2020 during a biodiversity survey that also collected high-resolution imagery and biological samples from a deep-water Remotely Operated Vehicle. Comparison of features between the two surveys indicates active sliding, minor headwall retreat and continued excavation of deep floor depressions, reflecting the action of high energy turbidity currents. Significantly, intact blades of displaced seagrass imaged throughout both canyons at depths up to 4200 m indicates that sediment sourced from the adjacent continental shelf is being channelled through these canyon systems. Sedimentation likely regulates benthic communities in these canyons, with imagery showing highest densities of sessile invertebrates in habitats protected from sedimentation (e.g. rock overhangs). Repeat mapping provides an understanding of the dynamics of these canyons and a context for assessing and monitoring the stability of the seabed habitats within a marine reserve. <b>Citation:</b> Alexandra L. Post, Rachel Przeslawski, Rachel Nanson, Justy Siwabessy, Deborah Smith, Lisa A. Kirkendale, Nerida G. Wilson, Modern dynamics, morphology and habitats of slope-confined canyons on the northwest Australian margin, <i>Marine Geology</i>, 2022, 106694, ISSN 0025-3227, https://doi.org/10.1016/j.margeo.2021.106694.

  • Remotely sensed data and updated DEM and radiometric datasets, combined with existing surface material and landform mapping were used to map regolith landform units for the Alice Springs study area of the SSC project. This report describes the methods used and outlines the new mapping.

  • <div>This data package contains interpretations of airborne electromagnetic (AEM) conductivity sections in the Exploring for the Future (EFTF) program’s Eastern Resources Corridor (ERC) study area, in south eastern Australia. Conductivity sections from 3 AEM surveys were interpreted to provide a continuous interpretation across the study area – the EFTF AusAEM ERC (Ley-Cooper, 2021), the Frome Embayment TEMPEST (Costelloe et al., 2012) and the MinEx CRC Mundi (Brodie, 2021) AEM surveys. Selected lines from the Frome Embayment TEMPEST and MinEx CRC Mundi surveys were chosen for interpretation to align with the 20&nbsp;km line-spaced EFTF AusAEM ERC survey (Figure 1).</div><div>The aim of this study was to interpret the AEM conductivity sections to develop a regional understanding of the near-surface stratigraphy and structural architecture. To ensure that the interpretations took into account the local geological features, the AEM conductivity sections were integrated and interpreted with other geological and geophysical datasets, such as boreholes, potential fields, surface and basement geology maps, and seismic interpretations. This approach provides a near-surface fundamental regional geological framework to support more detailed investigations. </div><div>This study interpreted between the ground surface and 500&nbsp;m depth along almost 30,000 line kilometres of nominally 20&nbsp;km line-spaced AEM conductivity sections, across an area of approximately 550,000&nbsp;km2. These interpretations delineate the geo-electrical features that correspond to major chronostratigraphic boundaries, and capture detailed stratigraphic information associated with these boundaries. These interpretations produced approximately 170,000 depth estimate points or approximately 9,100 3D line segments, each attributed with high-quality geometric, stratigraphic, and ancillary data. The depth estimate points are formatted for compliance with Geoscience Australia’s (GA) Estimates of Geological and Geophysical Surfaces (EGGS) database, the national repository for standardised depth estimate points. </div><div>Results from these interpretations provided support to stratigraphic drillhole targeting, as part of the Delamerian Margins NSW National Drilling Initiative campaign, a collaboration between GA’s EFTF program, the MinEx CRC National Drilling Initiative and the Geological Survey of New South Wales. The interpretations have applications in a wide range of disciplines, such as mineral, energy and groundwater resource exploration, environmental management, subsurface mapping, tectonic evolution studies, and cover thickness, prospectivity, and economic modelling. It is anticipated that these interpretations will benefit government, industry and academia with interest in the geology of the ERC region.</div>

  • <div><em>Seabed geomorphology</em> describes the shape and evolution of underwater landscapes. These landscapes interact with ocean currents to create diverse marine habitats. Similar to geological maps on land, maps of seabed geomorphology are vital for making informed decisions to support the sustainable growth of our Ocean Economy.</div><div><br></div><div>As we gather more detailed seabed data and face increasing ocean pressures, there's a need for new, standardised maps that support consistent decision making at multiple scales and between administrative jurisdictions. Dr Rachel Nanson and an international team have developed a new seabed geomorphology classification system that is designed to simplify complex seabed interpretations into a map format that is accessible to a broad range of end users.</div><div><br></div><div>This approach is being adopted internationally and is currently being implemented by Geoscience Australia. We are using the method to map parts of Australia’s extensive Marine Park network and to support government to make informed decisions regarding Australia’s rapidly expanding Offshore Renewable Energy sector</div>