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  • Monitoring is a regulatory requirement for all carbon dioxide capture and geological storage (CCS) projects to verify containment of injected carbon dioxide (CO2) within a licensed geological storage complex. Carbon markets require CO2 storage to be verified. The public wants assurances CCS projects will not cause any harm to themselves, the environment or other natural resources. In the unlikely event that CO2 leaks from a storage complex, and into groundwater, to the surface, atmosphere or ocean, then monitoring methods will be required to locate, assess and quantify the leak, and to inform the community about the risks and impacts on health, safety and the environment. This paper considers strategies to improve the efficiency of monitoring the large surface area overlying onshore storage complexes. We provide a synthesis of findings from monitoring for CO2 leakage at geological storage sites both natural and engineered, and from monitoring controlled releases of CO2 at four shallow release facilities - ZERT (USA), Ginninderra (Australia), Ressacada (Brazil) and CO2 field lab (Norway).

  • This dataset provides the spatially continuous data of seabed gravel (sediment fraction >2000 µm), mud (sediment fraction < 63 µm) and sand content (sediment fraction 63-2000 µm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.0025 decimal degree (dd) resolution raster grids format and ascii text file. The dataset covers the Petrel sub-basin in the Australian continental EEZ. This dataset supersedes previous predictions of sediment gravel, mud and sand content for the basin with demonstrated improvements in accuracy. Accuracy of predictions varies based on density of underlying data and level of seabed complexity. Artefacts occur in this dataset as a result of insufficient samples in relevant regions. This dataset is intended for use at the basin scale. The dataset may not be appropriate for use at smaller scales in areas where sample density is insufficient to detect local variation in sediment properties. To obtain the most accurate interpretation of sediment distribution in these areas, it is recommended that additional samples be collected and interpolations updated.

  • As part of the controlled release experiments at the Ginninderra test site, geophysical surveys have been acquired using electromagnetic techniques at a range of frequencies. The primary objective was to assess whether these could provide insight into the soil structure at the site, give guidance as to where to monitor for leakage, and provide additional information that may explain the observed sub-surface and surface CO2 migration behavior. A secondary objective was to assess whether CO2 leaks could be located based on secondary impacts such as drying of the soil profile. Ground penetrating radar surveys were taken during the second release experiment (October - December 2012). Different frequency shielded antennas were trialled in order to optimize the signal. Two surveys were conducted: one baseline survey prior to CO2 release and another during the release experiment. The GPR results show a reduction in range and clear reflections to the west indicating that clay was present. To the east we see clearer reflections from sand layers and the water table. These observations corresponded with larger scale sub-surface soil features determined from EM31 and EM38 electromagnetic surveys. Application of these geophysical surveys for CO2 leak detection and monitoring design are discussed. Paper for CO2CRC Research Symposium 2013

  • Poster for IAH 2013 A major concern for regulators and the public with geological storage of CO2 is the potential for the migration of CO2 via a leaky fault or well into potable groundwater supplies. Given sufficient CO2, an immediate effect on groundwater would be a decrease in pH which could lead to accelerated weathering, an increase in alkalinity and the release of major and minor ions. Laboratory and core studies have demonstrated that on contact with CO2 heavy metals can be released under low pH and high CO2 conditions (particularly Pd, Ni and Cr). There is also a concern that trace organic contaminants could be mobilised due to the high solubility of many organics in supercritical CO2. These scenarios potentially occur in a high CO2 leakage event, therefore detection of a small leak although barely perceptible could provide an important early warning for a subsequent and more substantial impact.

  • Geoscience Australia produces optimized statistical predictions of seabed sediment distribution for the Australian continental Exclusive Economic Zone. These products are broadly relevant to the work of government policy and research organizations and the offshore oil and gas industry. To better promote the features and relevance of these products, we need to produce 1-3 posters. These will provide graphic examples of the spatial predictions, comparisons between previous and recent versions of this dataset to demonstrate the increase in accuracy and resolution achieved, and provide information about how to access the data. These posters will be used to promote this work at relevant external workshops and conferences. We also need to produce some simple A4 size pamphlets/flyers based on the posters, which can be easily carried and distributed to various audiences. This would increase the awareness of GA's products in marine environmental geosciences, boost the usage of the products by both internal and external clients and promote GA's profile in generating quality geoscience information.

  • CO2CRC Symposium 2013: Oral presentation as part of a tag-team Ginninderra presentation As part of the controlled release experiments at the Ginninderra test site, a total of 14 soil flux surveys were conducted; 12 during the first experiment (March 2012 - June 2012), and 2 during the second experiment (October - December 2012). The aim was to determine what proportion of the known CO2 that was released could be measured using the soil flux method as a quantification tool. The results of this study enabled us to use the soil flux measurements as a proxy for other CO2 quantification methods and to gain an understanding of how the CO2 migrated within the sub-surface. For experiment one; baseline surveys were conducted pre-release, followed by surveys several times a week during the first stages of the release. The CO2 'breakthrough' was detected only 1 day after the release began. Surveys were then conducted weekly to monitor the flux rate over time. The soil CO2 flux gradually increased in magnitude until almost reaching the expected release rate (128 kg/day measured while the release rate was 144 kg/day) after approximately 4 weeks, and then receded quickly once the controlled release was stopped. Soil gas wells confirm that there is significant lateral migration of the CO2 in the sub-surface, suggesting that there was a degree of accumulation of CO2 in the sub-surface during the experiment.

  • The dry-tropics of central Queensland has an annual bushfire threat season that generally extends from September to November. Fire weather hazard is quantified using either the Forest Fire Danger Index (FFDI) or the Grassland Fire Danger Index (GFDI) (Luke and McArthur, 1978). Weather observations (temperature, relative humidity and wind speed) are combined with an estimate of the fuel state to predict likely fire behaviour if an ignition eventuates. A high resolution numerical weather model (dynamic downscaling) was utilised to provide spatial texture over the Rockhampton region for a range of historical days where bushfire hazard (as measured at the Rockhampton Airport meteorological station) was known to be severe to extreme. From the temperature, relative humidity and wind speeds generated by the model, the maximum FFDI for each simulated day was calculated using a maximum drought factor. Each of these FFDI maps was then normalised to the value of the FFDI at the grid point corresponding to Rockhampton Airport (ensemble produced). The annual recurrance interval (ARI) of FFDI at Rockhampton Airport for the current climate was calculated from observations by fitting Generalised Extreme Value (GEV) distributions. For future climate, we considered three downscaled General Circulation Models (GCM's) forced by the A2 emission scenario for atmospheric greenhouse gas emissions. The spatial pattern of the 50 and 100 year ARI fire danger rating for the Rockhampton region (current and future climate) was determined. In general, a small spatial increase in the fire danger rating is reflected in the ensemble model average for the 2090 climate. This is reflected throughout the Rockhampton region in both magnitude and extent through 2050 to 2090. Cluster areas of higher (future climate) bushfire hazard were mapped for planning applications. Handbook MODSIM2013 Conference

  • This dataset contains seascape classification layer derived from bathymetry and backscatter, and their derivative from seabed mapping surveys in Darwin Harbour. The survey was undertaken during the period 24 June to 20 August 2011 by iXSurvey Australia Pty Ltd for the Department of Natural Resources, Environment, The Arts and Sport (NRETAS) in collaboration with Geoscience Australia (GA), the Darwin Port Corporation (DPC) and the Australian Institute of Marine Science (AIMS) using GA's Kongsberg EM3002D multibeam sonar system and DPC's vessel Matthew Flinders. The survey obtained detailed bathymetric map of Darwin Harbour. Refer to the GA record ' Mapping and Classification of Darwin Harbour Seabed' for further information on processing techniques applied (GeoCat: 79212; GA Record: 2015/xx)

  • Monitoring is a regulatory requirement for all carbon dioxide capture and geological storage (CCS) projects to verify containment of injected carbon dioxide (CO2) within a licensed geological storage complex. Carbon markets require CO2 storage to be verified. The public wants assurances CCS projects will not cause any harm to themselves, the environment or other natural resources. In the unlikely event that CO2 leaks from a storage complex, and into groundwater, to the surface, atmosphere or ocean, then monitoring methods will be required to locate, assess and quantify the leak, and to inform the community about the risks and impacts on health, safety and the environment. This paper considers strategies to improve the efficiency of monitoring the large surface area overlying onshore storage complexes. We provide a synthesis of findings from monitoring for CO2 leakage at geological storage sites both natural and engineered, and from monitoring controlled releases of CO2 at four shallow release facilities - ZERT (USA), Ginninderra (Australia), Ressacada (Brazil) and CO2 field lab (Norway).

  • Changes in microbial diversity and population structure occur as a result of increased nutrient loads and knowledge of microbial community composition may be a useful tool for assessing water quality in coastal ecosystems. However, the ability to understand how microbial communities and individual species respond to increased nutrient loads is limited by the paucity of community-level microbial data. The microbial community composition in the water column and sediments was measured across tropical tidal creeks and the relationship with increased nutrient loads assessed by comparing sewage-impacted and non-impacted sites. Diversity-function relationships were examined with a focus on denitrification and the presence of pathogens typically associated with sewage effluent tested. Significant relationships were found between the microbial community composition and nutrient loads. Species richness, diversity and evenness in the water column all increased in response to increased nutrient loads, but there was no clear pattern in microbial community diversity in the sediments. Water column bacteria also reflected lower levels of denitrification at the sewage-impacted sites. The genetic diversity of pathogens indicated that more analysis would be required to verify their status as pathogens, and to develop tests for monitoring. This study highlights how microbial communities respond to sewage nutrients in a tropical estuary. Estuarine, Coastal and Shelf Science