This map is part of a series which comprises 50 maps which covers the whole of Australia at a scale of 1:1 000 000 (1cm on a map represents 10km on the ground). Each standard map covers an area of 6 degrees longitude by 4 degrees latitude or about 590 kilometres east to west and about 440 kilometres from north to south. These maps depict natural and constructed features including transport infrastructure (roads, railway airports), hydrography, contours, hypsometric and bathymetric layers, localities and some administrative boundaries, making this a useful general reference map.

This study brings together a wide range of datasets to provide a comprehensive assessment of the Pandurra Formation sedimentology and geochemistry in 3D. Sedimentology and geochemistry datasets generated this study are combined with pre-existing data to generate a 3D interpretation of the Pandurra Formation and improve understanding of how the Pandurra formation as we see it to today was deposited and subsequently post-depositionally mineralised.

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2012 Acreage Release information pack

Geomorphic landscape features and associated surface materials are fundamental to groundwater recharge processes as they form the first layer through which surface water passes before it becomes groundwater. Different surface materials exhibit different water-holding capacity and hence permeability characteristics. In the Broken Hill Managed Aquifer Recharge project, surface-materials mapping in conjunction with geomorphic mapping, has assisted hydrogeological investigations, including recharge predictions, salinity hazard and the identification of potential infiltration basins. Prior to landform identification, LiDAR DEM data was levelled using trend surfaces to eliminate regional slope (~20m). As a consequence of this, an ArcGIS interactive contour tool could be used to identify specific breaks in elevation associated with landform features. Multivariate image analysis of elevation, high resolution SPOT and Landsat-derived wetness further enhanced the contrast between geomorphic elements to confirm mapping boundaries. While specific landforms can be characterised by particular surface materials, these sediments can vary within a single geomorphic feature. Consequently, SPOT multispectral satellite imagery was used to identify surface materials using principal component analysis and unsupervised classification. This approach generated 20 classes; each assigned a preliminary cover/landform attribute using SPOT imagery. Field data (surface and borehole sample, and observations at shallow pits) were used to refine the classification approach. Interactive mapping using a de-trended DEM provided a rapid, effective and accurate alternative to time consuming manual landform digitisation. The combination of these two new products - surface-materials and geomorphic maps - has assisted in the identification of potential recharge sites and naturally occurring infiltration sites.

Seawater intrusion (SWI) is a problem globally due to changes in catchment water balances and rising sea levels. The northern coastline of Australia is an area of incipient SWI hazard; however, there is limited understanding of the characteristics of SWI. This study undertook a regional TEMPEST AEM survey of the Darwin coastal plains over the Koolpinyah Dolostone (KD) aquifer, to inform understanding of SWI in this important urban and peri-urban water source. Calibration and validation of AEM data involved sonic and rotary mud drilling, borehole geophysical and geological logging, and laboratory analysis of lithologies, pore fluids and groundwater samples. The AEM data provide greater spatial detail of critical elements of the hydrostratigraphy, and map a complex SWI interface in 3D. A potential SWI hazard to the main producing aquifer has been identified, with SWI ingress through preferential flow paths mapped along structural corridors. There is also extensive leakage of saline groundwater beneath the tidal Adelaide and Mary River floodplains. The existing regional hydrogeological model requires major revision to incorporate the significant weathered zones and salt stores, more restricted extent of dolostone in the aquifer,, and preferential recharge zones and groundwater flow paths to the KD aquifer identified through this study. Assessment of SWI risk to the groundwater resource requires additional hydrodynamic data targeted using the AEM data, and incorporation of results within a predictive groundwater model. The study demonstrates the value of regional, AEM surveys in understanding SWI proceses in karstic aquifers, particularly in data-poor, inaccessible or environmentally sensitive areas.

Map showing Australia's Maritime Jurisdiction in the Torres Strait. This map in an A4 simplified version of the Torres Strait map which is part of the 27 constituent maps of the "Australia's Maritime Jurisdiction Map Series" (Refer to GeoCat 73983 for original A4 map). Depicting various maritime zones. No background image on this map A4 sized JPG (stored within project - initially produced for Border Protection - GAMSA publication)

Traditional aquifer tests are an expensive and time-consuming method for obtaining hydraulic information. Furthermore, in many environments, it is becoming increasingly difficult to obtain environmental clearances to dispose produced waters. In this study, the Nuclear Magnetic Resonance (NMR) method was evaluated to provide data on hydraulic conductivities (K) and transmissivities (T) of sediments within the Darling River Floodplain, Australia. NMR data were acquired every 0.5 m using a slim-hole logging system in 26 sonic cored wells to a depth of ~70 m. KNMR can be estimated from the NMR measurements using the Schlumberger-Doll Research Equation: KNMR = C x ?2 x T2ML2, where is the NMR effective porosity, T2ML is the logarithmic mean of the T2 distributions, and C is a formation factor related to tortuosity. Prior to the calculation of the KNMR, the NMR data were classified into five hydraulic classes ranging from clay to gravely-coarse sand using the core, geophysical, mineralogical, and hyperspectral logs. In selected zones aquifer tests were conducted to provide constraints on the K and T of the formations. Least-squares inversion was used to solve for the optimum C values for each of the hydraulic classes versus the aquifer test obtained T. Comparisons between laboratory permeameter measurements and KNMR indicated correspondence within two orders of magnitude. The borehole NMR method provides a rapid way of estimating the near continuous variations in K through a sedimentary sequence, while also providing useful estimates of K at a scale not achievable using traditional aquifer testing methods.

During 2009-10 Geoscience Australia completed a petroleum prospectivity study in the offshore northern Perth Basin, 200 km northwest of Perth. In some parts of this basin acoustic basement is deep and not resolved in the reflection seismic data. Improvements to the magnetic ship-track database and magnetic anomaly grid produced during the study allowed for assessment of depth to magnetic sources, and estimation of sediment thickness, and provided new insight into basement trends. 2.5D models along several transects, and analysis using spectral methods indicate penetration of the lower sediments by high-susceptibility bodies is necessary to approximate the observed magnetic anomaly. The reflection seismic evidence for these bodies is not obvious, though in some cases they may be associated with interpreted faults. Where the modelled bodies penetrate the sediments, they are mostly below or within the Permian section, except in the west of the study area where sediments thin over oceanic crust. On the northern-most profiles a large positive magnetic anomaly (the Batavia Ridge) is modelled by massive bodies whose tops are 5-10 km below sea floor. On these and other profiles to the south other dyke-like bodies rarely penetrate to shallower than 5 km below the sea floor.

This framework is a reference for individuals and agencies involved in bushfire risk assessment in Australia who seek to improve information on bushfire risk from quantitative methods compared to qualitative methods. It is aimed at bushfire researchers and risk managers in fire, planning and related agencies. Computational bushfire risk assessment is in an early stage of development in Australia. It is an opportune time to establish a framework sufficiently broad that it will accommodate pre-existing and new methods to assess bushfire risk while encouraging innovation. Current methods for assessing bushfire risk in Australia use different terminologies and approaches, and application of an overarching framework improves the potential to compare methods and confidence in comparing results between studies.