Geoscience Australia carried out a marine survey on Carnarvon shelf (WA) in 2008 (SOL4769) to map seabed bathymetry and characterise benthic environments through colocated sampling of surface sediments and infauna, observation of benthic habitats using underwater towed video and stills photography, and measurement of ocean tides and wavegenerated currents. Data and samples were acquired using the Australian Institute of Marine Science (AIMS) Research Vessel Solander. Bathymetric mapping, sampling and video transects were completed in three survey areas that extended seaward from Ningaloo Reef to the shelf edge, including: Mandu Creek (80 sq km); Point Cloates (281 sq km), and; Gnaraloo (321 sq km). Additional bathymetric mapping (but no sampling or video) was completed between Mandu creek and Point Cloates, covering 277 sq km and north of Mandu Creek, covering 79 sq km. Two oceanographic moorings were deployed in the Point Cloates survey area. The survey also mapped and sampled an area to the northeast of the Muiron Islands covering 52 sq km. cloates_3m is an ArcINFO grid of Point Cloates of Carnarvon Shelf survey area produced from the processed EM3002 bathymetry data using the CARIS HIPS and SIPS software

GIS package for the Wilkinkarra region of Western Australia for the Palaeovalley Groundwater Project.

Understanding the distribution and abundance of sponges and their associated benthic habitats is of paramount importance for the establishment and monitoring of marine reserves. Benthic sleds or trawls can collect specimens for taxonomic and genetic research, but these sampling methods can be too qualititative for many ecological analyses and too destructive for monitoring purposes. Advances in the use of underwater videography and still imagery for biodiversity habitat mapping and modelling have been used within Geoscience Australia to extract data related to sponge biodiversity patterns across three regions. In the new Oceanic Shoals Commonwealth Marine Reserve, sponge morphologies were characterized from still images to locate areas in which biodiversity may be high due to habitat-forming taxa. In the Carnarvon Shelf abundance of a target sponge (Cinachyrella sp.) was quantified from video to investigate relationships between biology and sediment characteristics. Around Lord Howe Island, benthic habitats are being analysed to the national standard of classification using both video and still images. Importantly specialists within ecology, geophysics and spatial statistics work together to integrate biological and physical data to provide unique and meaningful maps of predicted distributions and habitat suitability for key ecological benthic habitats.

Geoscience Australia has collaboratively developed a number of open source software models and tools to estimate hazard, impact and risk to communities for a range of natural hazards to support disaster risk reduction in Australia and the region. These models and tools include: - ANUGA - a collaboration between the Australian National University (ANU) and GA to develop hydrodynamic software; - EQRM - earthquake risk model; - TCRM - tropical cyclone risk model; - PythonFall3D - python wrapper for an existing volcanic ash model; - TsuDAT - a collaboration between GA, the Australia-Indonesia Facility for Disaster Reduction, the ANU National Computing Infrastructure (NCI), OpenGeo and the World Bank to develop the tsunami data access tool; - RICS - rapid inventory collection system; - FiDAT - field data analysis tool. This presentation will discuss the drivers for developing these models in open source software and the benefits to the end-users in the emergency management and planning community as well as the broader research community. Key challenges in the risk modelling process will be discussed and how these may be addressed through the enhancement of existing models and the development of new models and workflows. Example challenges include image analysis for the development of building information from high resolution photography, project of future communities and reducing uncertainty in the frequency of natural hazard events. These challenges can be progressed through collaboration in the mathematical community.

Many countries in the Pacific rely heavily on their groundwater resources for drinking water, and for quite a few islands it is the only reliable source of water throughout the year. Changes in rainfall patterns and sea-level rise due to climate change are likely to threaten the availability and quality of groundwater in the future. Despite this threat, there is limited knowledge of the vulnerability of Pacific-Island aquifers to climate change at a regional scale. Currently, the sustainability of groundwater in the South Pacific is understood primarily through specific local-scale assessments of varying detail, with many locations unsurveyed. As the South Pacific is comprised of 1000s of small islands, it is not feasible to individually assess the groundwater resources of each island. Based on their geological makeup, South-Pacific Islands can be broadly classified as carbonate, continental, volcanic or composite (mixture of volcanic and carbonate) types. Previous hydrogeological investigations are generally biased towards carbonate-island types such as coral atolls and raised limestone islands and their associated fresh groundwater resources. However, in many of the South-Pacific Island countries volcanic-rock aquifers are also an important source of freshwater. This study aims to develop a systematic regional-scale typology for the Pacific Islands that considers all island situations, based primarily on hydrogeological characteristics. This will contribute to a hydrogeological framework in order to describe and understand how groundwater vulnerability to climate change differs between different hydrogeological settings and in different parts of the region. This will assist policy makers in the allocation of climate-change funding and monitoring, management and adaptation assistance.

The subsidence histories of most, but not all, basins can be elegantly explained by extension of the lithosphere followed by thermal rethickening of the lithospheric mantle to its pre-rift thickness. Although this model underpins most basin analysis, it is unclear whether subsidence of rift basins developed over thick lithosphere follows the same trend. Here the subsidence history of the Caning rift basin of Western Australia is modelled which putatively overlies lithosphere - 180 km thick, imaged using shear wave tomography. The entire subsidence history of the, < 300 km wide and <6 km thick, western Canning Basin is adequately explained by Ordovician rifting of ~120 km thick lithosphere followed by post-rift thermal subsidence as described by the established model. In contrast, the < 150 km wide and 15 km thick Fitzroy Trough of the eastern Canning Basin, reveals an almost continuous phase of normal faulting between Ordovician and Carboniferous Periods followed by negligible post-rift thermal subsidence which cannot be accounted for by the established model. This difference in basin architecture is attributed to rifting of thick lithosphere constrained by the presence of diamond bearing lamproites intruded into the basin depocentre at ~20 Ma. In order to account for the observed subsidence, at standard crustal densities, the lithospheric mantle is required to be depleted by 50-70 kg m-3. The actual depletion of the lowermost lithospheric mantle was assessed by modelling REE concentrations of the ~20 Ma lamproites along with other ultrapotassic rocks from the Kimberley, Yilgarn and Pilbara blocks which reveal a depletion of 40-70 kg m-3. Together these results suggest that thinning of thick lithosphere to thicknesses > 120 km is thermally stable and is not accompanied by post-rift thermal subsidence driven by thermal rethickening of the lithospheric mantle. The discrepancy between estimates of lithospheric thickness derived from subsidence data in the Western Canning and that derived from shear wave tomography suggests that the latter technique cannot resolve lithospheric thickness variations on < 300 km half wavelengths.

Since the 1989 Newcastle earthquake, the city of Newcastle, Australia, has become an extensive focus for earthquake hazard and risk assessment. The surficial geology varies between deeper alluvial deposits near the Hunter River, to shallower soils overlying weathered rock on the valley margins. Ambient vibration techniques, based on the dispersion property of surface waves in layered media, is one promising method for assessing the subsurface geophysical structure, in particular the shear-wave velocity (Vs). Using one such technique, the Spatial Auto-Correlation (SPAC) method, we characterise soil deposits at 23 sites in and around the city of Newcastle. Results show that values for soil overlying bedrock ranges from 200 m/s to 1000 m/s, with the higher velocity values observed in shallow soils which are relatively consolidated and far from river deposits. Bedrock depth varies from 6 to 56 m, but an accurate quantification is hampered by the low frequency picks (< 2 Hz) which are either unavailable or of dubious quality. Some shear-wave velocity profiles show two abrupt changes in Vs, the first ~ 4-15 m and the second ~19-56 m. Low Vs values are of particular interest as they may indicate areas of higher seismic hazard.

This report gives an overview of the activities of the Geoscience Australia IVS Analysis Center during 2012

2013 Acreage Release Areas W13-19 and W13-20 in the offshore northern Perth Basin, Western Australia, cover more than 19,000 km2 in parts of the Houtman, Abrolhos, Zeewyck and Gascoyne sub-basins. The Release Areas are located adjacent to WA-481-P, the only offshore exploration permit active in the Perth Basin, granted to joint venture partners Murphy Australia Oil Pty Ltd, Kufpec Australia Pty Ltd and Samsung Oil and Gas Australia Pty Ltd in September 2012. Geoscience Australia recently undertook a regional prospectivity study in the area as part of the Australian Government's Offshore Energy Security Program. A revised sequence stratigraphic framework, based on new biostratigraphic sampling and interpretation, and an updated tectonostratigraphic model, using multiple 1D burial history models for Permian to Cenozoic sequences, give fresh insights into basin evolution and prospectivity. Geochemical studies of key offshore wells demonstrated that the late Permian's Lower Triassic Hovea Member oil-prone source interval is regionally extensive offshore in the Abrolhos and potentially Houtman sub-basins. This is supported by fluid inclusion data that provides evidence for palaeo-oil columns within Permian reservoirs in wells from the Abrolhos Sub-basin. Additionally, oil trapped in fluid inclusions in Houtman-1 can be linked to Jurassic source rocks suggesting that multiple petroleum systems are effective in the Release Areas. A trap integrity analysis was undertaken to mitigate exploration risks associated with trap breach during Early Cretaceous breakup and provides a predictive approach to prospect assessment. Potential seepage sites on the seafloor over recently reactivated faults correlate with hydroacoustic flares, pockmarks and dark colored viscous fluid observed over the areas. These observations may indicate an active modern-day petroleum system in the Houtman Sub-basin. The presence of a Jurassic petroleum system combined with the extension of the Hovea Member source rock offshore, the potential presence of seeps and results from trap integrity studies provide a platform to revitalize exploration in the offshore northern Perth Basin. The APPEA Journal

This use of this data should be carried out with the knowledge of the contained metadata and with reference to the associated report provided by Geoscience Australia with this data (Reforming Planning Processes Trial: Rockhampton 2050). A copy of this report is available from the the Geoscience Australia website (http://www.ga.gov.au/sales) or the Geoscience Australia sales office (sales@ga.gov.au, 1800 800 173). The wind hazard outputs are a series of rasters, one for each average recurrence interval considered, presenting peak wind hazard (peak from all directions) as measure in km/h. This file presents the future climate wind hazard. The file name indicates the hazard being presented, e.g. wspd_rp_1000_max.tif is the 1000 year Return Period (RP - equivalent to Average Reccurrence Interval (ARI)) and is the maximum wind speed from all directions. The local wind multipliers adjust the 3-second gust regional RP wind speed from 10 m above ground level to ground level with the consideration of topography and shielding effects. Eight cardinal directions are calculated for every raster cell and the maximum of these values is then derived and presented here.