Geothermal energy is a renewable energy technology reported to have a large potential resource base. However, existing geothermal data for Australia (borehole temperatures and heat flow determinations), are limited and collection of additional data is both time consuming and restricted to accessing to wells drilled for other purposes. It is therefore important to develop "deposit" or resource models to aid exploration; improving the quality of subsurface thermal estimates, and helping to identify the distal footprints of geothermal systems. Conceptually, the fundamental requirements of a geothermal system are well understood. However, the complex interplay between the various elements makes it difficult to compare different geographical regions and to assess their relative prospectively. As such, the results of some 130,000 synthetic thermal-modelling runs have been used to calibrate a new tool called the 'Geothermal Calculator'. The Calculator acts as an emulator, or surrogate model, falling into a class of functions which seek to approximate the input / output behaviour of more-complex systems. This presentation will explore the mechanics of the Calculator, before examining some of its possible uses; from simple point-spot estimates to the broader continental scale. The functionality of the Geothermal Calculator presents a significant step forward in our ability to produce subsurface temperature estimates, and represents a notable milestone in the pathway to realising our subsurface geothermal energy potential.

The Frome airborne electromagnetic (AEM) survey is the largest of three regional AEM surveys flown under the 5-year Onshore Energy Security Program (OESP) by Geoscience Australia (GA). The aim of the survey is to reduce risk and stimulate exploration investment for uranium by providing reliable pre-competitive data. The Frome AEM survey was flown between 22 May and 2 November 2010, is approximately 95 450 km2 in area and collected 32 317 line km of new data at an average flying height of 100 m. The Frome AEM survey covers the Marree (pt), Callabonna (pt), Copley (pt), Frome (pt), Parachilna (pt), Curnamona, Olary and Chowilla (pt) 1:250 000 standard map sheets in South Australia and was flown largely at 2.5 km line spacing, with the northern portion flown at 5 km line spacing. GA partnered with, the Department of Primary Industries and Resources South Australia and an industry consortium. The survey results indicate a depth of investigation (DOI - depth of reliable signal penetration) of up to 400 m in areas of thin cover and resistive basement (e.g., Adelaidean rocks in the Olary Ranges). In Cenozoic - Mesozoic sediments in the Frome Embayment and the Murray Basin the DOI is up to 100-150 m. A range of under-cover features are revealed, including (but not limited to): extensions to known palaeovalley networks in the Frome Embayment; the under-cover extent of the Benagerie Ridge; regional faults in the Frome Embayment and Murray Basin; folded and faulted Neoproterozoic rocks in the Adelaide Fold Belt; Cenozoic - Mesozoic stratigraphy in the Frome Embayment; neotectonic offsets in the Lake Eyre Basin; conductive Neoproterozoic rocks associated with copper-gold mineralisation; and, coal-bearing structures in the Leigh Creek area, as well as groundwater features.

Aquifer characterisation and groundwater resources of Dili, East Timor

The formation of iron oxide copper-gold (IOCG) deposits requires the conjunction in time and space of four essential components of the ore-forming mineral system: (1) energy source(s) to motivate the flow of hydrothermal fluids; (2) sources of ore components (metals, sulphur) and fluids; (3) favourable 'architecture' of permeable pathways for fluids, and (4) physico-chemical gradient sites for ore deposition. These components have been identified for IOCG systems in northern Queensland and South Australia, focussing on uranium-bearing IOCG deposits, during multidisciplinary studies of the energy potential of these regions. Each of the four system components was mapped using existing and newly acquired geological, geophysical and geochemical data. Using mineral potential modelling based on established approaches, maps of potential for uranium-bearing IOCG deposits (and for other uranium mineral systems) were created for each of the two regions. In north Queensland the under-cover extensions of the IOCG province hosted by the Mt Isa Eastern Succession were identified as highly prospective for IOCG deposits, although the potential for uranium-bearing systems appears to be more limited due to the relatively deep crustal levels of exposure. Potential for Paleozoic IOCG systems was also identified in the Etheridge Province. In South Australia the well known early Mesoproterozoic Olympic IOCG Province in the eastern Gawler Craton is proposed to extend westwards via the Mt Woods Inlier into the Coober Pedy Ridge region. A key result is the identification of IOCG potential in the northern Curnamona Province, of equivalent age and setting to that in the Gawler Craton

The Broken Hill Managed Aquifer Recharge (BHMAR) project is part of a larger strategic effort aimed at securing Broken Hill's water supply and identifying significant water-saving measures for the Darling River system. In this study, airborne electromagnetics (AEM) mapping validated by drilling, field and laboratory measurements has identified significant volumes of fresh to acceptable quality groundwater stored beneath the Darling Floodplain. These potential resources were identified in 14 discrete targets within Pliocene aquifers (Calivil Formation and Loxton-Parilla Sands) at depths of 25-120m. The Calivil Formation occurs predominantly within structurally-controlled palaeovalleys. Aquifer quality is best where thick (30-50m), high-yielding zones (test flows > 25 L/s) occur in palaeochannels at the confluence of palaeo-river systems. Here, the hydraulic properties make the Calivil Formation aquifer best suited for groundwater extraction (and/or MAR injection), with excellent recovery efficiencies predicted where ambient salinities are low. The aquifer is sandwiched between variably thick clay aquitards, and is confined to semi-confined. Indicative groundwater volumes have been calculated using groundwater salinity and texture mapping derived for the AEM depth slices, combined with porosity statistics derived from laboratory measurements and borehole nuclear magnetic resonance (NMR) logging. In most of the targets, further investigation is required to quantify natural recharge and discharge processes, identify the negative impacts associated with groundwater pumping (particularly the potential for saline groundwater ingress), delineate the more transmissive parts of the formation, and assess the economics and logistics of borefield and water supply design. Calibrated, transient numerical groundwater flow and solute transport models are also needed to determine appropriate groundwater extraction rates. The multi-disciplinary systems-based methodology used in this project has enabled rapid identification and assessment of largely unknown potential groundwater resources and aquifer storage. These have the potential to provide drought security for regional communities and industries, and to assist with regional development.

Assessment of climate change impacts on groundwater in East Timor

Land cover data are an essential input into a wide array of models including land surface process models and weather/climate models. The Dynamic Land Cover Dataset is the first nationally consistent and thematically comprehensive land cover reference for Australia. It provides a basis for reporting on change and trends in vegetation cover and extent. The Dynamic Land Cover Dataset Version 2 is a suite of of ISO (ISO 19144-2) compliant land cover maps across the Australian landmass. The series of maps presents land cover information for every 250m by 250m area of the country for rolling two year intervals from 2001. Each map has been generated by applying a sophisticated time series analysis technique known as Dynamic Markov Chain modeling to two years of MODIS Enhanced Vegetation Index (EVI) data. The Dynamic Markov Chain modeling was used to classify each pixel based on the way that pixel has behaved over a two year period. The maps contain 33 land cover classes which reflect the structural character of vegetation, ranging from cultivated and managed land covers (crops and pastures) to natural land covers such as closed forest and open grasslands. The series of maps have been compared with over 30,000 independent ground data points provided by State, Territory and Federal Government agencies. The sequence of maps shows how Australian land cover is changing over time.

Volcanic ash represents a serious hazard to communities living in the vicinity of active volcanoes in developing countries like Indonesia. Geoscience Australia, the Australia-Indonesia Facility for Disaster Reduction (AIFDR) and the Indonesian Centre for Volcanology and Geohazard Mitigation (CVGHM) have adapted an existing open source volcanic ash dispersion model for use in Indonesia. The core model is the widely used volcanic ash dispersion model FALL3D. A python wrapper has been developed, which simplifies the use of FALL3D for those with little or no background in computational modelling. An application example is described here for Gunung Ciremai in West Java, Indonesia. Scenarios were run using eruptive parameters within the acceptable range of possible future events for this volcano, granulometry as determined through field studies and a meteorological dataset that represented a complete range of possible wind conditions expected during the dry and rainy seasons for the region. Implications for varying degrees of hazard associated with volcanic ash ground loading on nearby communities for dry versus rainy season wind conditions is discussed. Communities located on the western side of Gunung Ciremai are highly susceptible to volcanic ash ground loading regardless of the season whereas communities on the eastern side are found to be more susceptible during the rainy season months than during the dry. This is attributed to prevailing wind conditions during the rainy season that include a strong easterly component. These hazard maps can be used for hazard and impact analysis and can help focus mitigation efforts on communities most at risk.

Severe wind has major impacts on exposed human settlements and infrastructure, while climate change is expected to increase the severe wind hazard in many regions of Australia. The Risk and Impact Analysis Group (RIAG) in Geoscience Australia (GA) has developed a series of techniques to analyse the impact of severe wind imposed on the residential buildings under current and future climate. The process includes four components: hazard, exposure, vulnerability and risk. Severe wind hazard represents site specific wind speed values for different return periods (e.g. 500-year, 2000-year return periods), which may be derived by the wind loading standard (AS/NZS 1170.2), or be a result of modelling for current or future climates. GA has developed a National Exposure Information System (NEXIS), a repository of spatial and structural information of infrastructure exposed and vulnerable to natural hazards. NEXIS has also been extended to consider the number of future residential structures by utilising simple spatial relationships. Using an expert evaluation process, GA has developed a series of fragility curves which relate wind speed to the expected level of damage to residential buildings (measured as a percentage of the total replacement cost) in specific regions in Australia. These curves include consideration of factors such as building location, age, roof material, wall material, and so on. Given a certain intensity of severe wind imposed on a certain type of residential building in a specific region, the physical impact to a community can be determined in terms of the economic loss and casualties. By applying above concepts and procedures, based on sample data from the selected cities, we have integrated these three components (hazard, residential buildings exposure and vulnerability) within a computational framework to derive severe wind risk under both current climate and for a range of climate scenarios. These processes will be utilised for the assessment of climate change adaptation strategies concerning structural wind loading.

One of the important inputs to a probabilistic seismic hazard assessment is the expected rate at which earthquakes within the study region. The rate of earthquakes is a function of the rate at which the crust is being deformed, mostly by tectonic stresses. This paper will present two contrasting methods of estimating the strain rate at the scale of the Australian continent. The first method is based on statistically analysing the recently updated national earthquake catalogue, while the second uses a geodynamic model of the Australian plate and the forces that act upon it. For the first method, we show a couple of examples of the strain rates predicted across Australia using different statistical techniques. However no matter what method is used, the measurable seismic strain rates are typically in the range of 10-16s-1 to around 10-18s-1 depending on location. By contrast, the geodynamic model predicts a much more uniform strain rate of around 10-17s-1 across the continent. The level of uniformity of the true distribution of long term strain rate in Australia is likely to be somewhere between these two extremes. Neither estimate is consistent with the Australian plate being completely rigid and free from internal deformation (i.e. a strain rate of exactly zero). This paper will also give an overview of how this kind of work affects the national earthquake hazard map and how future high precision geodetic estimates of strain rate should help to reduce the uncertainty in this important parameter for probabilistic seismic hazard assessments.