Sub-glacial geothermal heat flow is acknowledged to be a critical, yet poorly constrained, boundary parameter influencing ice sheet behaviour (Winsborrow et al 2010). Geothermal heat flow is the sum of residual heat from the formation of the Earth and the natural heat generated within the Earth from the radiogenic decay of the major heat producing elements (HPEs), U, Th and K. Estimates of the sub-glacial geothermal heat flow in Antarctica are largely deduced from remotely-sensed low-resolution datasets such as seismic tomography or satellite-based geomagnetics. These methods provide broad regional estimates of geothermal heat flow reflecting variations in the mantle contribution as a function of thickness of a thermally homogeneous crust. These estimates of sub-glacial geothermal heat flow, although widely utilised in ice sheet modelling studies, fail to account for lateral and vertical heterogeneity of heat production within the crust where HPEs are concentrated and that are known to significantly impact regional geothermal heat flow values. Significant variations in regional geothermal heat flow due to heterogeneous crustal distribution of HPEs have been recognised within southern Australia (e.g. McLaren et al., 2006), a region that was connected to east Antarctica along the George V, Adélie and Wilkes Lands coastline prior to breakup of Gondwana. The South Australian Heat Flow Anomaly (SAHFA; e.g. Neumann et al., 2000) is characterized by surface heat flows as high as 126 mWm-2, some '2-3 times' that of typical continental values, due to local enrichment of HPEs. The SAHFA forms part of a once contiguous continental block called the Mawson Continent, a now dismembered crustal block that is known, from geological and geophysical evidence, to extend deep into the sub-glacial interior of the Antarctic. It is highly probable that the high geothermal heat flow characteristics of the SAHFA also extend into the sub-glacial hinterland of Terra Adélie and George V lands, a possibility that has not been previously considered in ice sheet studies. In order to account for the occurrence of several sub-glacial lakes in Adélie Land, Siegert & Dowdeswell (1996) concluded that 'a further 25-50 mWm-2 of equivalent geothermal heat' was required over the assumed local geothermal heat flow of ca. 54 mWm-2. Although that study concluded that the additional heat required for basal melting was derived from internal ice deformation, they also acknowledged the possible role of variations in geothermal heat flow, and now that the SAHFA is well characterised, this is a possibility that appears very likely.

Exploration models for Rot Rock geothermal energy plays in Australia are based primarily on high-heat producing granites (HHPG) in combination with overlying low-conductivity sedimentary rocks providing the insulator necessary to accumulate elevated temperatures at unusually shallow (therefore accessible) depths. Unknowns in this style of geothermal play include the composition and geometry of the HHPG and thermal properties, and the thickness of the overlying sediments. A series of 3D geological models have been constructed to investigate the range of geometries and compositions that may give rise to prospective Hot Rock geothermal energy plays. A 3D geological map of the Cooper Basin region which contains known HHPG beneath thick sedimentary sequences, has been constructed from gravity inversions and constrained by geological data. The inversion models delineate regions of low density within the basement that are inferred to be granitic bodies. Thermal forward modelling was carried out by incorporating measured and estimated thermal properties to the mapped lithologies. An enhancement of the GeoModeller software is to allow the input thermal properties to be specified as distribution functions. Multiple thermal simulations using Monte-Carlo methods would be carried out from the supplied distributions. Statistical methods will be used to yield the probability estimates of the in-situ heat resource, reducing the risk of exploring for heat. The two thermal modelling techniques can be used as a predictive tool in regions where little or no temperature and geological data are available.

Energy drives the modern world and underpins our current way of life. The industrial age was fuelled by access to reliable high grade energy sources, such as coal and oil, which drove global economic expansion and modernisation. There is a strong correlation between energy consumption levels and GDP. Australia is a large consumer of energy (5.87 Tonnes of oil equivalent per person annually), ranking twentieth on total consumption, and 16th on a per-capita basis. Australia is well endowed with traditional energy resources, e.g., coal, gas, uranium, and is a large energy producer (8th in the world). Australia also benefits from energy exports. Energy, therefore, strongly contributes to the nation's wealth and living standards, but increasingly it is recognised that these are dependent on access to cheap energy. Environmental concerns and the for the need energy security will drive a switch to other more sustainable energy types, preferably from indigenous energy sources. Although the Australia continent is ideally situated to make use of many alternate energies, e.g., our hot and arid nature makes solar an ideal potential renewable energy source, such sources will not provide all of our needs and will not contribute to peak energy loads. Fortuitously, Australia is endowed with above average concentrations of the radioactive elements (K, U and Th) in many of our rocks. Australia has ~38% of the world's current uranium reserves. The energy generated by the naturally-occurring break down of radioactive elements is immense, and this energy can be captured either by fission of U (and Th?) in nuclear reactors, or by the use of geothermal energy. Combined, both sources have the ability to meet base and peak load power requirements, and the potential to underpin Australia's energy requirements well into the future.

This is a 3 minute movie (with production music), to be played in the background during the October 28th 2010 Geoscience Australia Parlimentary Breakfast. The video shows a wide range of the types of activities that GA is involved in. These images include GA people doing GA activities as well as some of the results of offshore surveys; continental mapping; eath monitoring etc. The movie will be played as a background before and after GA's CEO (Chris Pigram) presentation.

Like many of the basins along Australia's eastern seaboard, there is currently only a limited understanding of the geothermal energy potential of the New South Wales extent of the Clarence-Moreton Basin. To date, no study has examined the existing geological information available to produce an estimate of subsurface temperatures throughout the region. Forward modelling of basin structure using its expected thermal properties is the process generally used in geothermal studies to estimate temperatures at depth in the Earth's crust. The process has seen increasing use in complex three-dimensional (3D) models, including in areas of sparse data. The overall uncertainties of 3D models, including the influence of the broad assumptions required to undertake them, are generally only poorly examined by their authors and sometimes completely ignored. New methods are presented in this study which will allow estimates and uncertainties to be addressed in a quantitative and justifiable way. Specifically, this study applies Monte Carlo Analysis to constrain uncertainties through random sampling of statistically congruent populations. Particular focus has been placed on the uncertainty in assigning thermal conductivity values to complex and spatially extensive geological formations using only limited data. As a case study these new methods are then applied to the New South Wales extent of the Clarence-Moreton Basin. The geological structure of the basin has been modelled using data from existing petroleum drill holes, surface mapping and information derived from previous studies. A range of possible lithological compositions was determined for each of the major geological layers through application of compositional data analysis. In turn, a range of possible thermal conductivity values was determined for the major lithology groups using rock samples held by the NSW Department of Primary Industries (DPI). These two populations of values were then randomly sampled to establish 120 different forward models, the results of which have been interpreted to present the best estimate of expected subsurface temperatures, and their uncertainties. These results suggest that the Clarence-Moreton Basin has a moderate geothermal energy potential within an economic drilling depth. This potential however, displays significant variability between different modelling runs, which is likely due to the limited data available for the region. While further work could improve these methods, it can be seen from this study that uncertainties can provide a means by which to add confidence to results, rather than undermine it.

Synthetic thermal modelling, constrained by available geological and geophysical datasets, is used to aid in geothermal target identi9fication and prioritization

Educational factsheet discussing geothermal induced seismicity, what it is, why it happens, potential risks and mitigation strategies. Short abstract from factsheet header below: Hot Rock geothermal power production relies on using buried hot rocks to heat water and generate electricity. Australia is thought to have an enormous geothermal resource, capable of providing low-emission, cost-competitive energy for centuries to come. The nature of most Hot Rock resources in Australia necessitates artificial enhancement of the resources to make them viable for geothermal power production. One possible hazard associated with developing geothermal resources is induced seismicity. Induced seismicity is the term used to describe earthquakes generated by human activities. Induced earthquakes are associated with the movement of material into or out of the earth, for example during water reservoir filling, underground mining, and development of Hot Rock reservoirs. Exploration for geothermal energy in Australia has rapidly increased over the last five years, and geothermal exploration leases have been taken out around Melbourne, Adelaide, Hobart and Geelong. If shown to have viable geothermal resources, geological enhancement of these areas for Hot Rock power production may generate induced seismicity. However, experience in Australia to date suggests that the risks associated with geothermal induced seismicity are very low compared to that of natural earthquakes, and can be reduced by careful management and monitoring.

This volume is a compilation of Extended Abstracts presented at the 2008 Australian Geothermal Energy Conference, 19-22 August 2008, Rydges Hotel, Melbourne, organised by the Australian Geothermal Energy Association and the Australian Geothermal Energy Group. This Conference is the first dedicated conference organised by the geothermal energy community in Australia and has been made possible by the seed funding from the Australian Government under the Sir Mark Oliphant Conference funding scheme with additional sponsorship of the companies acknowledged earlier and paying delegates. This Conference is being held at a time of rapid growth in all sectors of the geothermal community. The number of companies engaged in exploration stands at 33, the number of leases held or applied for is 320, and the value of the work program for these companies exceeds $850 million between 2002-2013. The Australian Geothermal Energy Association has been incorporated to serve as the peak industry representative body. The Universities of Queensland, West Australia, Adelaide and Newcastle have new funding specifically for geothermal research programs. The Australian Government has continued its strong support of the sector through the Geothermal Industry Development Framework and Technology Roadmap, the Geothermal Drilling Program, and the Onshore Energy Security Program. All of the States now have legislation regulating geothermal exploration activity in place, and the Northern Territory has drafted legislation for presentation to parliament. This volume of Extended Abstracts starts with a summary snapshot of the global and national geothermal energy sectors. The rest of the volume is organised under three headings: Underground Science and Technology Power Conversion Technologies Legislation, Policy and Infrastructure

As part of the Onshore Energy and Security Program Geoscience Australia are producing regional geothermal energy assessments. The initial assessment (Huston, 2010) was conducted in the North Queensland region with a further assessment to be completed in the Gawler-Curnamona region, South Australia. The assessments, which incorporate geological, geophysical, geochemical and rock property data, identify geographic regions of high prospectivity for Hot Rock (HR) and Hot Sedimentary Aquifer (HSA) systems. The North Queensland assessment, consisting of a map of HR and HSA potential ranked from high to low was produced using GIS techniques. A heat production layer of polygons ranked from high to low was generated from solid geology maps and geochemical data. Heat production values for the lithologies were calculated using concentrations of radiogenic elements (U, K and Th). A thermal resistance ranking layer was produced by integrating thermal conductivity data with sediment thickness data. A temperature availability ranking layer was also generated based on the predicted temperature at 5 km using AUSTHERM07 database. The ranked layers were weighted based on their prospectivity potential and in conjunction with data uncertainty rankings,combined in the GIS to produce the final HR prospectivity map. To produce the HSA prospectivity map, aquifer thickness and water temperature ranking layers were added to the HR assessment.

The development of the Australian geothermal industry over the last decade owes much to compilations of drill hole temperature data undertaken in the early 1990s in Canberra. The portrayal of this data on maps of predicted temperature at five kilometres depth, and contained heat resource calculations from this data, have shifted the perception that because Australia does not have significant current magmatic activity there is no geothermal potential. The Australian geothermal industry arguably now leads the world in terms of development of amagmatic geothermal systems for electricity generation.