https://nova.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41879 Tue 15 Nov 2022 15:01:54 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:43768 2 geological storage involves injection of supercritical CO₂ into a suitable reservoir with a structural trap from an overlying seal. Unconventional and conventional reservoirs provide opportunities for beneficial use such as enhanced recovery, supercritical CO₂ fracturing, and storage of gases such as CO₂ and ancillary gases, or potentially hydrogen. The purpose of this study is to use Australian examples of unconventional rock packages to understand the controls on CO₂ reactivity and mineral trapping (the most secure form of storage) and to demonstrate if there is potential for storage in unconventional reservoirs. Characterization of core from the Surat, Eromanga, and Cooper basins, is used to populate geochemical models and compare the potential for mineral trapping of CO₂. Interburden from a coal seam gas reservoir ranged from clay rich mudstones to interlaminated and calcite cemented sandstones. The interburden samples contained high plagioclase and chlorite mineral content and these were predicted in geochemical dissolved CO₂-production water-rock reactivity models to alter to calcite, ankerite, siderite and dawsonite mineral trapping 4 - 12 kg CO₂ per m3. CO₂ mineral trapping as siderite and ankerite in quartz rich oil sandstone was predicted to be lower than in interburden. Gas shale samples and black oil shales also contained a high mica, chlorite and feldspar content that can be converted to carbonate minerals, mineral trapping CO₂. Unconventional rock packages have strong potential for mineral trapping during CO₂ storage. In future a combination of characterization, CO₂ experiments and models should be performed for reservoirs and seals from sites of interest to understand initial changes to poro-perm. Several sandstones characterized here showed indicators of natural CO₂ or acidic fluid alteration with carbonates and clays filling natural fractures. Characterizing regions, where gases have been stored naturally and carbonates precipitated are valuable to validate long term predictions. Understanding the CO₂ storage potential of different reservoirs will also have applicability to future hydrogen storage.]]> Tue 14 Nov 2023 14:51:44 AEDT ]]>