Integrated Petrophysical and Geomechanical Assessment of Reservoir for CO2 Storage in the Bredasdorp Basin, South Africa

Summary South Africa’s total CO2 emissions in 2023 amounted to over 400 million tons, with global warming and climate change already a major concern worldwide. Hence, CO2 emitters such as South Africa have pledged to achieve net-zero carbon emissions by 2050. However, given South Africa’s reliance on coal, the push to establish a low-carbon economy must be carried out sustainably. In the pursuit of a low-carbon economy, this opens up the possibility of developing carbon capture and storage (CCS) systems that can provide dependable remedial actions. This study evaluates the AF Reservoir as a potential long-term CO2 storage formation in South Africa’s Bredasdorp Basin, using petrophysical and geomechanical methods. This was accomplished through a thorough review of wireline and core data available from a depleted hydrocarbon field. Based on reservoir parameters and geomechanical features, the findings of this study imply that the AF reservoir has a promising potential for CO2 storage, leading to a more comprehensive assessment of CO2 storage in the Bredasdorp Basin. However, additional studies, including coupled dynamic reservoir modelling and geomechanical modelling of the reservoir sand-AF and caprock, will allow for the optimisation of the CO2 injection approach to predict/avoid any potential reservoir and overburden deformation.