This dataset is a Gocad sgrid format of The Cooper Basin 3D Map Version 2: Thermal Modelling and Temperature Uncertainty released in August 2012 (Meixner et al., 2012). The Cooper Basin 3D Map Version 2 was produced from 3D inversions of Bouguer gravity data using geological data to constrain the inversions. The 3D map delineates regions of low density within the basement of the Cooper/Eromanga Basins that are inferred to be granitic bodies. The 3D map was originally released in two Gocad formats: surfaces and a voxet. Here it is presented as an sgrid. References: Meixner, A.J., Kirkby, A.L., Lescinsky, D.T., and Horspool, N.H., 2012. The Cooper Basin 3D map Version 2: Thermal Modelling and Temperature Uncertainty. Geoscience Australia Record 2012/60.

An extension of previously developed methods to calculate in-situ 3D temperature directly from 3D geology models in 3D GeoModeller software now allows for quantification of the uncertainty associated with those calculations. This work is being collaboratively undertaken by Intrepid Geophysics and Geoscience Australia, and will offer Australia's geothermal industry both: i) a new predictive tool helping to reduce the risk of Enhanced Geothermal System (EGS) exploration and heat resource estimation, and ii) stochastic temperature and heat flow maps of Australia.

Current understanding of the temperature distribution in the Australian continent is based on sparse and unevenly distributed borehole temperature measurements, and even fewer heat flow determinations. To address this, the Geothermal Project at Geoscience Australia (GA), initiated under the $58.9M Onshore Energy Security Program, has established a capability for determining surface heat flow across the country through temperature logging and thermal conductivity measurement. This abstract describes the GA heat flow data collection programme, its current status, and potential applications for the new data that is being collected.

Extended abstract describing metallogenic significance of georgina-Arunta seismic line. The abstract discusses mainly the Neoproterozoic and Phanerozoic mineral potential, including implications to U, Cu-Co, Au, Cu-U and energy.

The hot rock geothermal model in the Australian context comprises high-heat producing granites overlain by thick accumulations of low-thermal conductivity sediments. The granites have low concentrations of radiogenic elements, and over hundreds of millions of years, these elements decay and produce heat. The passage of this heat to the Earth's surface via upwards conduction is slowed by layers of sediments that have low thermal conductivity, creating 'hot spots' beneath the blankets. This thematic map shows granites attributed by heat production and basin depth. The majority of the granites depicted are of surface outcrop. The presence of high-heat producing granites adjacent to deep sedimentary basins may be used as a first-order indicator of where to further investigate the possibility of hot rock geothermal plays. The main frame of the map shows all granites (attributed by calculated heat production - where available), sedimentary basins (and their order e.g. where one basin is overlapped by another) and geothermal licences and applications. The top right inset map shows only those granites with a calculated radiogenic heat generation of >5 uW -3, with the depth of the sedimentary basins. This map provides a rapid view of areas that may be expected to have the greatest hot rock potential. The second-from-top inset map shows all suitable geochemical analyses from OZCHEM, attributed by calculated radiogenic heat generation. This shows both the distribution of data that goes into attributing the granite polygons, and also analyses of granites (and other rocks) that fall outside the mapped granite polygons that are otherwise excluded from the main map. The third-from-top inset map shows the distribution of drillholes with temperature measurements. The bottom inset map shows an image of the Austherm07 database, which is derived from the drillhole temperature information. The image shows the projected temperature of the crust at a depth of 5 kilometres, interpolated between the drillholes. Overlain on this image is the small number of publicly-available heat flow data.

The hot rock geothermal model in the Australian context comprises high-heat producing granites overlain by thick accumulations of low-thermal conductivity sediments. The granites have low concentrations of radiogenic elements, and over hundreds of millions of years, these elements decay and produce heat. The passage of this heat to the Earth's surface via upwards conduction is slowed by layers of sediments that have low thermal conductivity, creating "hot spots" beneath the blankets. This thematic map shows granites attributed by heat production and basin depth. The majority of the granites depicted are of surface outcrop. The presence of high-heat producing granites adjacent to deep sedimentary basins may be used as a first-order indicator of where to further investigate the possibility of hot rock geothermal plays. The main frame of the map shows all granites (attributed by calculated heat production where available), sedimentary basins and their order (e.g. where one basin is overlapped by another) and geothermal licenses and applications. The top right inset map shows only those granites with a calculated radiogenic heat generation of >5 Wm-3, and the depths of the sedimentary basins. This map provides a rapid view of areas that may be expected to have the greatest hot rock potential. The second-from-top inset map shows all suitable geochemical analyses from OZCHEM, attributed by calculated radiogenic heat generation. This shows both the distribution of data that goes into attributing the granite polygons, and also analyses of granites (and other rocks) that fall outside the mapped granite polygons and are otherwise excluded from the main map. The third-from-top inset map shows the distribution of drillholes that have temperature measurements. The bottom inset map shows an image of the Austherm07 database, which is derived from the drillhole temperature information. The image shows the projected temperature of the crust at a depth of 5km, interpolated between the drillholes. Overlain on this image is the small number of publicly-available heat flow data. This map is GA GeoCat record 65306. ISBN (print): 978-1-921236-44-0; ISBN (web): 978-1-921236-45-7. Webpage: http://www.ga.gov.au/minerals/research/national/geothermal/index.jsp.

The economic viability of geothermal energy depends on the depth that must be drilled to reach the required temperature. This depends on the geothermal gradient, which varies vertically and horizontally in the Earth's crust. Traditionally these variations in geothermal gradient have been interpreted in terms of thermal conduction. However, advection and convection influence the temperature distribution in some sedimentary basins. Convection can cause the temperature gradient to vary significantly with depth, such that temperature estimates derived from extrapolation of shallow temperature gradients could be misleading. We use borehole temperature measurements in the Perth Basin (Western Australia) and the Cooper Basin (South Australia and Queensland) to reveal spatial variations in the geothermal gradient, and consider whether these patterns are indicative of convection.

The Habanero Engineered Geothermal System (EGS) in central Australia has been under development since 2002, with several deep (more than 4000 m) wells drilled into the high-heat-producing granites of the Big Lake Suite to date. Multiple hydraulic stimulations have been performed to improve the existing fracture permeability in the granite. The stimulation of the newly-drilled Habanero-4 well (H-4) was completed in late 2012, and micro-seismic data indicated an increase in total stimulated reservoir area to approximately 4 km². Two well doublets have been tested, initially between Habanero-1 (H-1) and Habanero-3 (H-3), and more recently, between H-1 and H-4. Both doublets effectively operated as closed systems and excluding short-term flow tests, all production fluids were re-injected into the reservoir at depth. Two inter-well tracer tests have been conducted since 2008, to evaluate the fluid residence time in the reservoir alongside other hydraulic properties, and to provide comparative information to assess the effectiveness of the hydraulic stimulations. The closed-system and discrete nature of this engineered geothermal reservoir provides a unique opportunity to explore the relationships between the micro-seismic, rock property, production and tracer data. The most recent inter-well tracer test occurred in June 2013, which involved injecting 100 kg of 2,6 naphthalene-disulfonate (NDS) into H-1 to evaluate the hydraulic characteristics of the newly-created H-1/H-4 doublet. Sampling of the production fluids from H-4 occurred throughout the duration of the 3-month closed-circulation test. After correcting for flow hiatuses (i.e. interruptions in injection and production) and non-steady-state flow conditions, tracer breakthrough in H-4 was observed after 6 days (compared to ~4 days for the previous H-1/H-3 doublet), with peak breakthrough occurring after 17 days. Applying moment analysis to the data indicated that approximately 56% of the tracer was returned during the circulation test (vs. approximately 70% from the 2008 H-1/H-3 tracer test). This suggests that a considerable proportion of the tracer may lie trapped in the opposite end of the reservoir from H-4 and/or may have been lost to the far field. Flow capacity:storage capacity plots derived from the H-1/H-4 tracer test indicate that the Habanero reservoir is moderately heterogeneous, with approximately half of the flow travelling via around 25% of the pore volume. The calculated inter-well swept pore volume was approximately 31,000 m³, which is larger than that calculated for the H-1/H-3 doublet (~20,000 m³). This is consistent with the inferred increase in reservoir volume following hydraulic stimulation of H-4.

This volume is a compilation of Extended Abstracts presented at the 2010 Australian Geothermal Energy Conference, 17-19 November 2010, Adelaide Convention Centre, Adelaide, organised by the Australian Geothermal Energy Association and the Australian Geothermal Energy Group.

Australia's emergent geothermal energy industry is growing rapidly. So far, 29 companies have applied for geothermal exploration licenses. The majority of these companies are prospecting for Hot Rock geothermal resources for electricity generation, with some companies targeting hydrothermal resources. The Hot Rock model in the Australian context comprises a thick sequence (>3km) of low-thermal conductivity sediments overlying deeper high-heat-producing granites. Until now, the key dataset available to industry to guide their geothermal exploration has been a map of crustal temperature at 5km depth1. Compiled from temperature measurements made in 5,722 petroleum wells across Australia, the map indicates a vast geothermal resource. Additional national-scale geothermal datasets are either incomplete, not publicly accessible, or have not been collected. In August 2006, the Australian Government announced an Energy Security Initiative. It provides $58.9M to Geoscience Australia (the national geoscience and spatial information agency) over five years for an Onshore Energy Security Program (OESP). The OESP aims to better understand Australia's geological potential for onshore energy resources such as petroleum, uranium and geothermal, and includes the acquisition of new seismic, radiometric, heat-flow, magneto-telluric, gravity, magnetic, geochemical and drill-hole data. Providing new data will help attract company exploration in new areas by enhancing the chances of discovery and reducing the risks to investors. Established as part of the OESP, a new Geothermal Energy Project will generate precompetitive geoscientific information for geothermal explorers through two major activities: creating maps of heat distribution across Australia, and developing a geothermal information system. Heat distribution will be mapped in three ways: (1) new heat flow measurements in existing and new drill-holes; (2) a granite source-sediment heat trap map to identify Hot Rock systems; and (3) enhancements to the 5km-temperature-map method of Chopra and Holgate1. The geothermal information system will include thermal conductivity, thermal gradient, geochemistry, density, and heat production amongst other data types. The Australian Government is also facilitating and funding the preparation of a Geothermal Industry Development Framework, which is being lead by the Department of Industry, Tourism and Resources. The Development Framework aims to support the growth of Australia's geothermal industry by identifying opportunities and impediments to the industry's growth, and developing strategies to ensure that technical, economic and regulatory obstacles are tackled in a coordinated way. 1 Chopra, P. and Holgate, F., (2005) A GIS analysis of temperature in the Australian crust, Proceedings of the World Geothermal Congress 2005, Antalya, Turkey, 24-29 April 2005.