From 1 - 10 / 91
  • Groundwater has been sampled from 21 shallow (Port Campbell Limestone) and 3 deep (Dilwyn Formation) groundwater bores within a radius of 10 km around well CRC-1 between June 2006 and March 2008. The objectives of the study are (1) to establish baseline aquifer conditions prior to CO2 injection at CRC-1, which started in April 2008, and (2) to enable detection monitoring for CO2 leakage, should any occur in the future. In addition to sampling, standing water levels have been monitored continuously in 6 of the bores using barometric loggers. The water samples were analysed for pH, electrical conductivity (EC), temperature (T), dissolved oxygen (DO), redox potential (Eh), reduced iron (Fe2+) and alkalinity (dissolved inorganic carbon, DIC, as HCO3-) in the field, and for a suite of major, minor and trace inorganic species in the laboratory. Stable isotopes of O and H in water, of S in sulfate and of C and O in DIC were also determined. The shallow groundwaters have compositions typical of carbonate aquifer hosted waters, being fresh (EC 800-4000 uS/cm), dominated by Ca, Na, HCO3- and Cl-, cool (T 12-23°C), and near-neutral (pH 6.6-7.5). Most deep groundwater samples are similarly fresh or fresher (EC 400-1600 uS/cm), also dominated by Ca, Na, HCO3- and Cl-, cool (T 15-21°C), but are more alkaline (pH 7.5-9.5). Time-series reveal that parameters measured have been relatively stable over the sampling period, although some shallow bores display increasing EC and T, some show decreasing then increasing alkalinity while others show steadily increasing alkalinity (with or without increasing Cl- and Na, and decreasing Ca). Alkalinity of the deep groundwater tends to decrease slightly over the period. Groundwater levels in some of the shallow bores show a seasonal variation with longer term trends evident in both aquifers.

  • The critical success factors which control hydrocarbon prospectivity in the Otway Basin have been investigated using petroleum systems approaches. Greater than 99% of the hydrocarbon inventory within the Victorian Otway Basin has been sourced from Austral 2 (Albian-Aptian) source rocks and these accumulations are typically located either within, or within approximately 3,000 m of source rock kitchens which are at peak thermal maturity at present day. Importantly, the zones of greatest prospectivity are located where these source rocks have been actively generating and expelling hydrocarbons throughout the Late Tertiary, primarily as a result of sediment loading associated with progradation of the Heytesbury shelfal carbonates. This peak generation window occurs at an average depth of approximately 2,500-3,500 m 'sub-mud' across much of the basin, which has allowed prospective hydrocarbon fairways to be mapped out, thereby highlighting areas of greatest prospectivity. It is believed that the spatial proximity of the actively generating source rocks to the accumulations is due to several factors, which includes overall poor fault seal in the basin (success cases occur where charge rate exceeds leakage rate) and relatively complex and tortuous migration fairways (which means that large volumes of hydrocarbons are only focussed and migrate for relatively short distances). etc

  • In mid 2011 the Australian Government announced funding of a new four year National CO2 Infrastructure Plan (NCIP) to accelerate the identification and development of sites suitable for the long term storage of CO2 in Australia that are within reasonable distances of major energy and industrial CO2 emission sources. The NCIP program promotes pre-competitive storage exploration and provides a basis for the development of transport and storage infrastructure. The Plan follows on from recommendations from the Carbon Storage Taskforce and the National CCS Council (formerly, the National Low Emissions Coal Council). It builds on the work funded under the National Low Emissions Coal Initiative and the need for adequate storage to be identified as a national priority. Geoscience Australia is providing strategic advice in delivering the plan and will lead in the acquisition of pre-competitive data. Four offshore sedimentary basins (Bonaparte, Browse, Perth and Gippsland basins) and several onshore basins have been identified for pre-competitive data acquisition and study. The offshore Petrel Sub-basin is located in Bonaparte Basin, in NW Australia, has been identified as a potential carbon storage hub for CO2 produced as a by-product from future LNG processing associated with the development of major gas accumulations on the NW Shelf. The aim of the project is to determine if the sub-basin is suitable for long-term storage, and has the potential capacity to be a major storage site. The project began in June 2011 and will be completed by July 2013. As part of the project, new 2D seismic data will be acquired in an area of poor existing seismic coverage along the boundary of the two Greenhouse Gas Assessment Areas, which were released in 2009.

  • Quantification of leakage into the atmosphere from geologically stored CO2 is achievable by means of atmospheric monitoring techniques if the position of the leak can be located and the perturbation above the background concentration is sufficiently large for discrimination. Geoscience Australia and the CO2CRC have recently constructed a site in northern Canberra for the controlled release of greenhouse gases. This facility enables the simulation of leak events and provides an opportunity to investigate techniques for the detection and quantification of emissions of CO2 (and other greenhouse gases) into the atmosphere under controlled conditions. The facility is modelled on the ZERT controlled release facility in Montana. The first phase of the installation is complete and has supported an above ground, point source, release experiment (e.g. simulating leakage from a compromised well). Phase 2 involves the installation of a shallow underground horizontal well for line source CO2 release experiments and this will be installed during the first half of 2011. A release experiment was conducted at the site to explore the application of a technique, termed atmospheric tomography, to simultaneously determine the location and emission rate of a leak when both are unknown. The technique was applied to the release of two gas species, N2O and CO2, with continuous sampling of atmospheric trace gas concentrations from 8 locations 20m distant from a central release point and measurement of atmospheric turbulence and dispersive conditions. The release rate was 1.10 ± 0.02 g min-1 for N2O and 58.5 ± 0.4 g min-1 for CO2 (equivalent to 30.7 ± 0.2 tonnes CO2 yr-1). Localisation using both release species occurred within 0.5 m (2% error) of the known location. Determination of emission rate was possible to within 7% for CO2 and 5% for N2O.

  • Geological Storage Potential of CO2 & Source to Sink Matching Matching of CO2 sources with CO2 storage opportunities (known as source to sink matching), requires identification of the optimal locations for both the emission source and storage site for CO2 emissions. The choice of optimal sites is a complex process and can not be solely based on the best technical site for storage, but requires a detailed assessment of source issues, transport links and integration with economic and environmental factors. Many assessments of storage capacity of CO2 in geological formations have been made at a regional or global level. The level of detail and assessment methods vary substantially, from detailed attempts to count the actual storage volume at a basinal or prospect level, to more simplistic and ?broad brush? approaches that try to estimate the potential worldwide (Bradshaw et al, 2003). At the worldwide level, estimates of the CO2 storage potential are often quoted as ?very large? with ranges for the estimates in the order of 100?s to 10,000?s Gt of CO2 (Beecy and Kuuskra, 2001; Bruant et al, 2002; Bradshaw et al 2003). Identifying a large global capacity to store CO2 is only a part of the solution to the CO2 storage problem. If the large storage capacity can not be accessed because it is too distant from the source, or is associated with large technical uncertainty, then it may not be possible to reliably predict that it would ever be of value when making assessments. To ascertain whether any potential storage capacity could ever be actually utilised requires analysis of numerous other factors. Within the GEODISC program of the Australian Petroleum Cooperative Research Centre (APCRC), Geoscience Australia (GA) and the University of New South Wales (UNSW) completed an analysis of the potential for the geological storage of CO2. Over 100 potential Environmentally Sustainable Sites for CO2 Injection (ESSCIs) were assessed by applying a deterministic risk assessment (Bradshaw et al, 2002). At a regional scale Australia has a risked capacity for CO2 storage potential in excess of 1600 years of current annual total net emissions. However, this estimate does not incorporate the various factors that are required in source to sink matching. If these factors are included, and an assumption is made that some economic imperative will apply to encourage geological storage of CO2, then a more realistic analysis can be derived. In such a case, Australia may have the potential to store a maximum of 25% of our total annual net emissions, or approximately 100 - 115 Mt CO2 per year.

  • In July 2010 Geoscience Australia and CSIRO Marine & Atmospheric Research jointly commissioned a new atmospheric composition monitoring station (' Arcturus') in central Queensland. The facility is designed as a proto-type remotely operated `baseline monitoring station' such as could be deployed in areas that are likely targets for commercial scale carbon capture and geological storage (CCS). It is envisaged that such a station could act as a high quality reference point for later in-fill, site based, atmospheric monitoring associated with geological storage of CO2. The station uses two wavelength scanned cavity ringdown instruments to measure concentrations of carbon dioxide (CO2), methane (CH4), water vapour and the isotopic signature (?13C) of CO2. Meteorological parameters such as wind speed and wind direction are also measured. In combination with CSIRO's TAPM (The Air Pollution Model), data will be used to understand the local variations in CO2 and CH4 and the contributions of natural and anthropogenic sources in the area to this variability. The site is located in a region that supports cropping, grazing, cattle feedlotting, coal mining and gas production activities, which may be associated with fluxes of CO2 and CH4. We present in this paper some of the challenges found during the installation and operation of the station in a remote, sub-tropical environment and how these were resolved. We will also present the first results from the site coupled with preliminary modelling of the relative contribution of large point source anthropogenic emissions and their contribution to the background.

  • Within the GEODISC program of the Australian Petroleum Cooperative Research Centre (APCRC), Geoscience Australia (GA) and the University of New South Wales (UNSW) completed an analysis of the potential for the geological storage of CO2. The geological analysis produced an assessment from over 100 potential Environmentally Sustainable Sites for CO2 Injection (ESSCI) by applying a deterministic risk assessment. Out of 100 potential sites, 65 proved to be valid sites for further study. This assessment examined predominantly saline reservoirs which is where we believe Australia?s greatest storage potential exists. However, many of these basins also contain coal seams that may be capable of storing CO2. Several of these coal basins occur close to coal-fired power plants and oil and gas fields where high levels of CO2 are emitted. CO2 storage in coal beds is intrinsically different to storage in saline formations, and different approaches need to be applied when assessing them. Whilst potentially having economic benefit, enhanced coal bed methane (ECBM) production through CO2 injection does raise an issue of how much greenhouse gas mitigation might occur. Even if only small percentages of the total methane are liberated to the atmosphere in the process, then a worse outcome could be achieved in terms of greenhouse gas mitigation. The most suitable coal basins in Australia for CO2 storage include the Galilee, Cooper and Bowen-Surat basins in Queensland, and the Sydney, Gunnedah, and Clarence-Moreton Basins in New South Wales. Brief examples of geological storage within saline aquifers and coal seams in the Bowen and Surat basins, Queensland Australia, are described in this paper to compare and contrast each storage option.

  • This GHGT-12 conference paper hightlights some results of GA's work on "Regional assessment of the CO2 storage potential of the Mesozoic sucession in the Petrel Sub-basin, Northern Territory, Australia. Record 2014/11".

  • A Bayesian inversion technique to determine the location and strength of trace gas emissions from a point source in open air is presented. It was tested using atmospheric measurements of nitrous oxide (N2O) and carbon dioxide (CO2) released at known rates from a source located within an array of eight evenly spaced sampling points on a 20 m radius circle. The analysis requires knowledge of concentration enhancement downwind of the source and the normalized, three-dimensional distribution (shape) of concentration in the dispersion plume. The influence of varying background concentrations of ~1% for N2O and ~10% for CO2 was removed by subtracting upwind concentrations from those downwind of the source to yield only concentration enhancements. Continuous measurements of turbulent wind and temperature statistics were used to model the dispersion plume. The analysis localized the source to within 0.8 m of the true position and the emission rates were determined to better than 3% accuracy. This technique will be useful in assurance monitoring for geological storage of CO2 and for applications requiring knowledge of the location and rate of fugitive emissions.