Matching of CO2 emission sources with storage opportunities or source/sink matching (SSM), involves the integration of a number of technical, social and economic issues. It 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 will not rest solely on the best technical site for storage, but will require a detailed assessment of source issues, transport links and integration with economic and environmental factors. Transport is one of the major costs in CO2 sequestration and in many instances it will strongly influence how locations are chosen, but itself will be dependent on what type of facilities are to be built, be they either onshore or offshore or a combination of both. Comparison of theoretical studies, and the numerous criteria they utilise in their assessments, with current or planned commercial operations indicates that it is only a few of the major criteria that determine site locations.

Geoscience Australia is conducting a study under the National Carbon Infrastructure Plan (NCIP) to assess the suitability of the Vlaming Sub-basin for CO2 storage. It involves characterisation of the Valanginian reservoir (Gage Sandstone) and the Early Cretaceous seal (South Perth Shale) by integrating seismic interpretation and well log analysis in a detailed sequence stratigraphic investigation. The Gage Sandstone, comprised of channelised turbidites and mass flows, was the first unit deposited after breakup between India and Australia. Deposited during a sea level lowstand in the palaeo-topographic lows of the breakup unconformity, it is overlain by a thick deltaic to shallow marine succession of the South Perth Shale. The Gage Sandstone is considered one of the best reservoirs in the sub-basin with porosities of 23-30% and permeabilities of 200-1800 mD. It occurs at depths between 1000 and 3000 m below the seafloor, which makes, it an attractive target for the injection and long-term storage of supercritical CO2. The new extent of the Gage Sandstone, based on seismic interpretation and well log correlation, shows that in some of the wells the sandstone unit overlying the Valanginian unconformity belongs to the South Perth Shale and not to the Gage Sandstone. The G. Mutabilis palynological zone used in the past for identifying Gage Sandstone interval appears to be facies controlled and time transgressive. Detailed analysis of the reservoir properties at the wells in conjunction with systematic seismic facies mapping will serve as a basis for a regional reservoir model and storage potential estimation of the Gage Sandstone reservoir.

A question and answer style brochure on geological storage of carbon dioxide. Questions addressed include: - What is geological storage? - Why do we need to store carbon dioxide? - How can you store anything in solid rock? - Could the carbon dioxide contaminate the fresh water supply? - Could a hydrocarbon seal leak? - Are there any geological storage projects in Australia?

The Petrel Sub-basin Marine Survey GA-0335 (SOL5463) was undertaken by the RV Solander during May 2012 as part of the Commonwealth Government's National Low Emission Coal Initiative (NLECI). The survey was a collaboration between the Australian Institute of Marine Science (AIMS) and GA. The purpose was to acquire geophysical and biophysical data on shallow (less then 100m water depth) seabed environments within two targeted areas in the Petrel Sub-basin to support investigation for CO2 storage potential in these areas. This dataset contains identifications of animals collected from 21 Smith-McIntyre grabs deployed during GA-334. Biological specimens were collected from Smith-McIntyre grabs. Sediment was elutriated for ~ 5 minutes over a 500um sieve. Retained sediments and animals were then preserved in 70% ethanol for later laboratory sorting and identification (see 'lineage'). The dataset is current as of November 2012, but will be updated as taxonomic experts contribute. Stations are named XXGRYY where XX indicates the station number, GR indicates Smith-Mac grab, and YY indicates the sequence of grabs deployed (i.e. the YYth grab on the entire survey).

The CO2CRC has been leading the international development and application of atmospheric techniques for CO2 leak detection and quantification for CCS. CSIRO's atmospheric monitoring program at the CO2CRC Otway Project demonstrated world's leading practice for atmospheric monitoring at geological storage sites. The GA-CO2CRC Ginninderra controlled release facility has enabled development and testing of a new atmospheric tomography approach for accurately quantifying CO2 emissions using atmospheric techniques. A scaled-up version of the technique using an array of more cost effective (but less accurate) sensors was applied at a larger scale at the Otway Stage 2B controlled release. Additional techniques have been developed including data filtering to optimize the detection of emitted gases against the ecosystem background and Bayesian inverse modeling to locate and quantify a source. GA and CSIRO operate a joint baseline atmospheric station in the Bowen Basin and have been independently investigating the sensitivity of CO2 leak detection through coupling of measurements taken in a sub-tropical environment with simulated leakage events. An outcome from this body of work is the importance of good quality, calibrated measurements, a long baseline record and the development and application of techniques using atmospheric models for quantifying gaseous emissions from the ground to the atmosphere. These same measurement requirements and quantification techniques have direct application to fugitive methane emissions from open cut coal mines, coal seam gas, tight gas, and conventional gas emissions. Application is easier for methane: the background signal is lower, sensors are available at affordable cost, and the emissions are measureable now. The Bowen Basin site, for example, is detecting fugitive methane emitted from open cut coal mining activities tens of kilometres away. An example of the sensitivity of atmospheric techniques for the detection of fugitive emissions from a simulated methane source will be presented.

The survey was undertaken as a collaboration between Geoscience Australia and the Australian Institute of Marine Science (AIMS). The purpose was to acquire geophysical and biophysical data on shallow (less than 100 m water depth) seabed environments within two targeted areas in the Petrel Sub-basin to support investigation for CO2 storage potential in these areas. Sub bottom profiler data were acquired using a sparker source and a 24 channel streamer, and processed as shallow, high resolution, multi-channel seismic reflection data.

The Petrel Sub-basin Marine Survey GA-0335 (SOL5463) was undertaken on RV Solander during May 2012 as part of the Commonwealth Government's National Low Emission Coal Initiative (NLECI). The survey was a collaboration between the Australian Institute of Marine Science (AIMS) and GA. The purpose was to acquire geophysical and biophysical data on shallow (less than 100 m water depth) seabed environments within two targeted areas in the Petrel Sub-basin to support the investigation of CO2 storage potential in these areas. Unconsolidated surface (seabed) sediments were collected at 11 sampling stations using a Smith_McIntyre grab (10L volume). Sediment samples were collected to provide data on a) sedimentology, b) infauna and c) the geochemical composition of the sediments. For the sedimentology (this dataset) up to 250 g of sediment was sub-sampled from the surface (0-2 cm) of the sediment recovered in the Smith_McIntyre grabs. Sub-samples were described from visual inspection, noting grain size, sorting and composition and these were stored in plastic bags and refrigerated. These were subsequently analysed at the GA laboratories to provide information on the texture and composition of the sediments at the sampling locations. Grain size measurement was undertaken by wet sieving to determine mud (<63 microns), sand (63-2000 microns) and gravel (>2000 microns) fractions as percentage of dry weight. A separate sub-sample (~1g) was used for laser diffraction measurement of the mud and sand fractions using a Malvern Mastersizer 2000, with results expressed as percentage of the total particle volume based on an average of three measurements on each sample. Particle size distributions including mean, median, and standard deviation, together with skewness and kurtosis indices were calculated. Separate sample splits were taken for measurement of the carbonate content using the carbonate bomb method following Muller and Gastner (1979).

Questions often asked by the public in regard to the concept of CO2 storage include; "But won?t it leak?", and "How long will it stay down there?". The natural environment of petroleum systems documents many of the processes which will influence CO2 storage outcomes, and the likely long (geological) timeframes that will operate. Thousand of billions of barrels of hydrocarbons have been trapped and stored in geological formations in sedimentary basins for 10s to 100s of millions of years, as has substantial volumes of CO2 that has been generated through natural processes. Examples from Australia and major hydrocarbon provinces of the world are documented, including those basins with major accumulations that are currently trapped in their primary reservoir, those that have accumulated hydrocarbons in the primary reservoir and then through tectonic activity spilled them to other secondary traps or released the hydrocarbons to the atmosphere, and those that generated hydrocarbons but for which no effective traps were in place for hydrocarbons to accumulate. Some theoretical modelling of the likelihood of meeting stabilisation targets using geological storage are based on leakage rates which are implausibly high when compared to observations from viable storage locations in the natural environment, and do not necessarily account for the likelihood of delay times for leakage to the atmosphere or the timeframe in which geological events will occur. Without appropriate caveats, they potentially place at risk the public perception of how efficient and effective appropriately selected geological reservoirs could be for storage of CO2. If the same rigorous methods, technology and skills that are used to explore for, find and produce hydrocarbon accumulations are now used for finding safe and secure storage sites for CO2, the traps so identified can be expected to contain the CO2 after injection for similar periods of time as that in which hydrocarbons and CO2 have been stored in the natural environment.

Identification of major hydrocarbon provinces from existing world assessments for hydrocarbon potential can be used to identify those sedimentary basins at a global level that will be highly prospective for CO2 storage. Most sedimentary basins which are minor petroleum provinces and many non-petroliferous sedimentary basins will also be prospective for CO2 storage. Accurate storage potential estimates will require that each basin be assessed individually, but many of the prospective basins may have ranges from high to low prospectivity. The degree to which geological storage of CO2 will be implemented in the future will depend on the geographical and technical relationships between emission sites and storage locations, and the economic drivers that affect the implementation for each source to sink match. CO2 storage potential is a naturally occurring resource, and like any other natural resource there will be a need to provide regional access to the better sites if the full potential of the technology is to be realized. Whilst some regions of the world have a paucity of opportunities in their immediate geographic confines, others are well endowed. Some areas whilst having good storage potential in their local region may be challenged by the enormous volume of CO2 emissions that are locally generated. Hubs which centralize the collection and transport of CO2 in a region could encourage the building of longer and larger pipelines to larger and technically more viable storage sites and so reduce costs due to economies of scale.

A study of the geological prospectivity for carbon dioxide subsurface storage in selected member economies of the APEC (Asia-Pacific Economic Cooperation) region was recently completed. The study is part of a multi-phase program of the APEC Energy Working Group to promote sustainable energy development within the APEC community. APEC economies considered in this study including the Republic of Korea, China, Indonesia, Malaysia, Philippines, Chinese Taipei and Thailand. The objective of the study is to establish a sound understanding of the relationship between the key emission sources and the prospective basins that may contain potential storage sites, and to derive a qualitative assessment of whether the storage potential available in a specific country will meet its storage requirements through the foreseeable future. China has very high emissions and moderate to high prospectivity for storage and Indonesia, Malaysia and Thailand have moderate emissions and moderate storage prospectivity. The Philippines have low emissions and low storage prospectivity, whereas the Republic of Korea and Chinese Taipei both have high emissions and low storage prospectivity.