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  • Total contribution of six recently discovered submerged coral reefs in northern Australia to Holocene neritic CaCO3, CO2, and C is assessed to address a gap in global budgets. CaCO3 production for the reef framework and inter-reefal deposits is 0.26-0.28 Mt which yields 2.36-2.72 x105 mol yr-1 over the mid- to late-Holocene (<10.5 kyr BP); the period in which the reefs have been active. Holocene CO2 and C production is 0.14-0.16 Mt and 0.06-0.07 Mt, yielding 3.23-3.71 and 5.32-6.12 x105 mol yr-1, respectively. Coral and coralline algae are the dominant sources of Holocene CaCO3 although foraminifers and molluscs are the dominant constituents of inter-reefal deposits. The total amount of Holocene neritic CaCO3 produced by the six submerged coral reefs is several orders of magnitude smaller than that calculated using accepted CaCO3 production values because of very low production, a 'give-up' growth history, and presumed significant dissolution and exports. Total global contribution of submerged reefs to Holocene neritic CaCO3 is estimated to be 0.26-0.62 Gt or 2.55-6.17 x108 mol yr-1, which yields 0.15-0.37 Gt CO2 (3.48-8.42 x108 mol yr-1) and 0.07-0.17 Gt C (5.74-13.99 x108 mol yr-1). Contributions from submerged coral reefs in Australia are estimated to be 0.05 Gt CaCO3 (0.48 x108 mol yr-1), 0.03 Gt CO2 (0.65 x108 mol yr-1), and 0.01 Gt C (1.08 x108 mol yr-1) for an emergent reef area of 47.9 x103 km2. The dilemma remains that the global area and CaCO3 mass of submerged coral reefs are currently unknown. It is inevitable that many more submerged coral reefs will be found. Our findings imply that submerged coral reefs are a small but fundamental source of Holocene neritic CaCO3, CO2, and C that is poorly-quantified for global budgets.

  • Groundwater monitoring around the CO2CRC Otway Project CO2 injection site aims to (1) establish baseline aquifer conditions prior to CO2 injection, and (2) enable detection monitoring for CO2 leakage, in the unlikely event any should occur in the future. The groundwater composition was monitored at 24 bores around the site for nearly 2 years before injection started. The water samples were analysed for standard bulk properties, and inorganic chemical and isotopic compositions. In addition to sampling, standing water levels were monitored continuously in 6 of the bores using barometric loggers. The shallow groundwaters have compositions typical of carbonate aquifer-hosted waters, being fresh (EC 800-4000 S/cm), dominated by Ca2+, Na+, HCO3- and Cl-, cool (T 12-23°C), and near-neutral (pH 6.6-7.5). Most of the deep groundwater samples are fresher (EC 400-1600 S/cm), also dominated by Ca2+, Na+, HCO3- and Cl-, cool (T 15-21°C), but are more alkaline (pH 7.5-9.5). Time-series reveal that most parameters measured have been relatively stable over the sampling period, although some bores display changes that appear to be non-seasonal. Groundwater levels in some of the shallow bores show a seasonal variation with longer term trends evident in both aquifers.

  • 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 of 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 and geological studies to assess storage potential. Four offshore sedimentary basins (Bonaparte, Browse, Perth and Gippsland basins) and several onshore basins have been identified for pre-competitive data acquisition and study.

  • Geoscience Australia and CO2CRC have constructed a greenhouse gas controlled release facility to simulate surface emissions of CO2 (and other greenhouse gases) from the soil into the atmosphere under controlled conditions. The facility is located at an experimental agricultural station maintained by CSIRO Plant Industry at Ginninderra, Canberra. The design of the facility is modelled on the ZERT controlled release facility in Montana. The facility is equipped with a 2.5 tonne liquid CO2 storage vessel, vaporiser and mass flow controller unit with a capacity for 6 individual metered CO2 gas streams (up to 600 kg/d capacity in total). Injection of CO2 into the soil is via a 120m long slotted HDPE pipe installed horizontally 2m underground. This is equipped with a packer system to partition the well into six CO2 injection chambers. The site is characterised by the presence of deep red and yellow podsolic soils with the subsoil containing mainly kaolinite and subdominant illite. Injection is above the water table. The choice of well orientation based upon the effects of various factors such as topography, wind direction, soil properties and ground water depth will be discussed. An above ground release experiment was conducted from July - October 2010 leading to the development of an atmospheric tomography technique for quantifying and locating CO2 emissions1. An overview of monitoring experiments conducted during the first subsurface release (January-March 2012), including application of the atmospheric tomography technique, soil flux surveys, microbiological surveys, and tracer studies, will be presented. Additional CO2 release experiments are planned for late 2012 and 2013. Poster presented at 11th Annual Conference on Carbon Capture Utilization & Sequestration, April 30 - May 3, 2012, Pittsburgh, Pennsylvania

  • Geoscience Australia and CO2CRC have constructed a greenhouse gas controlled release reference facility to simulate surface emissions of CO2 (and other GHG gases) from an underground slotted horizontal well into the atmosphere under controlled conditions. The facility is located at an experimental agricultural station maintained by CSIRO Plant Industry at Ginninderra, Canberra. The design of the facility is modelled on the ZERT controlled release facility in Montana. The facility is equipped with a 2.5 tonne liquid CO2 storage vessel, vaporiser and mass flow controller unit with a capacity for 6 individual metered CO2 gas streams (up to 600 kg/d capacity). Injection of CO2 into soil is via a shallow (2m depth) underground 120m horizontally drilled slotted HDPE pipe. This is equipped with a packer system to partition the well into six CO2 injection chambers. The site is characterised by the presence of deep red and yellow podsolic soils with the subsoil containing mainly kaolinite and subdominant illite. Injection is above the water table. The choice of well orientation based upon the effects of various factors such as topography, wind direction, soil properties and ground water depth will be discussed. An above ground release experiment was conducted from July - October 2010 leading to the development of an atmospheric tomography technique for quantifying and locating CO2 emissions1. This technique will be applied to the first sub-surface experiment held in January-March 2012 in addition to soil flux surveys, microbiological surveys, and tracer studies. An overview of monitoring experiments conducted during the subsurface release and preliminary results will be presented. Additional CO2 releases are planned for late 2012 and 2013. Abstract for "11th Annual Conference on Carbon Capture Utilization & Sequestration" April 30 - May 3, 2012, Pittsburgh, Pennsylvania

  • The Australian Government, through the Department of Resources, Energy and Tourism, has supported Geoscience Australia in undertaking a series of regional-scale, geological studies to assess the CO2 storage potential of sedimentary basins, including the Petrel Sub-basin. The studies form part of the National Low Emissions Coal Initiative designed to accelerate the development of CO2 transport and storage infrastructure near the sources of major energy and industrial emissions. The Petrel Sub-basin was identified as a high-priority region for a future pre-competitive work program by the national Carbon Storage Taskforce. The Carbon Storage Taskforce also recommended the release of greenhouse gas assessment permits, which were released within the Petrel Sub-basin in 2009. As a component of the studies at Geoscience Australia, the numerical simulation was hypothetically designed to dynamically model the reservoir behavior and CO2 migration during the injection and post-injection stages using an in-house built 3D geological model of a represented injection site. 14 million tonnes per annum (MTPA) of CO2 was injected into the lower Frigate/Elang/Plover reservoir over 30 years and CO2 plume migration was simulated up to 2,000 years from the initial injection. The injection rate of 14 MTPA of CO2 used in this study was based on the predicted 2020 CO2 emissions of the Darwin Hub, a figure defined by the Carbon Storage Taskforce (2009). The poster highlights the simulation results including CO2 plume migration distance, CO2 trapping mechanisms and reservoir pressure behavior.

  • Abstract for submission to 11th IEA GHG International Conference on Greenhouse Gas Control Technologies. Conference paper to follow pending selection for oral or poster presentation. Abstract covers the GA-ACCA21 China Australia Geological Storage of CO2 (CAGS) Project run through PMD/ED 2009-2012.

  • Australia has become the first country to offer commercial offshore acreage for the purpose of storing greenhouse gases in geological formations. Ten offshore areas in five basins/sub-basins are open for applications for Assessment Permits, which will allow exploration in those areas for suitable geological formations and conditions for storage of greenhouse gases (predominantly CO2). The acreage was released on the 27th March 2009 under the Offshore Petroleum and Greenhouse Gas Storage Act 2006. The acreage release is modelled on Australia's annual Offshore Petroleum Acreage Release; applicants can apply for an Assessment Permit for any of the ten areas, which is approximately equivalent to an exploration permit in petroleum terms. Applications will be assessed on a work-bid basis and other selection criteria outlined in the Regulations and Guidance Notes for Applicants. Following the assessment period, project proponents may apply for an injection license (equivalent to a production license in the petroleum industry) to inject and store greenhouse gas substances in the permit area. The areas offered in this first round of Acreage Release include five areas located within the Gippsland and Otway basins, offshore Victoria and South Australia, and the other five areas are located in the Vlaming and Petrel sub-basins, offshore Western Australia and the Northern Territory. The offshore areas offered for GHG geological storage assessment are significantly larger than their offshore petroleum counterparts to account for, and fully contain, the expected migration pathways of the injected GHG substances.

  • 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.

  • Accurate seismic velocity model is essential for depth conversion and rock property determination in the context of fluid flow modelling to support site selection for secure storage of carbon dioxide. The Bonaparte CO2 Storage project funded by the Australian Government will assess the carbon dioxide geological storage potential of two blocks in the Petrel Sub-basin on the Australian NW Margin. These blocks were offered as part of the 2009 release of offshore areas for greenhouse gas (GHG) storage assessment. The Petrel Sub-basin is a northwest-trending Paleozoic rift within the southern Bonaparte Basin. The geological reservoirs of interest include the Jurassic Plover Formation and the Early Cretaceous Sandpiper Sandstone. Primary and secondary seals of interest include the Late Jurassic Frigate Formation and the Cretaceous Bathurst Island Group (regional seal). Trapping mechanisms for injected CO2 may include faulted anticlines, stratigraphic traps, salt diapirs and/or migration dissolution and residual trapping. Water depths are generally less than 100m and depths to reservoir/seal pairs range between 800-2500m below the sea surface. All three main types of seismic velocity measurements are available within the area of our study: velocities derived from stacking of multi-channel reflection seismic data; velocities determined in the process of ray tracing modelling of large offset refraction data acquired by the ocean bottom seismographs (OBS) along the coincident reflection/refraction transect, and velocities from well log (sonic, vertical seismic profiling and check shot) measurements.