Development of a Weighting Procedure for the Geomechanical Parameters Involved in CO2 Storage

This research focuses on a methodological study of the fault activation mechanisms associated with carbon dioxide (CO2) storage, with a focus on determining the underlying geomechanical properties of the caprock. The study uses an analytic hierarchy process (AHP) to prioritize these parameters in order to improve the process for selecting the critical geomechanical design data that underpin the analysis of potential CO2 storage sites. By integrating expert knowledge through a structured questionnaire, this study extends the process and provides a weighting methodology to provide realistic parameters as input for advanced numerical simulations. The ratings achieved indicated that the injection pressure was the most significant parameter, while fault cohesion was found to be the least significant parameter, having minimal impact on fault displacement. To validate the weighting methodology, a sensitivity analysis was performed using numerical modeling based on these parameters. The results confirmed the accuracy of the weighting methodology, demonstrating that injection pressure is indeed the most critical factor, while fault cohesion has the least impact on displacement. Additionally, the study advances our understanding of key geomechanical parameters, facilitating the development of customized CO2 injection and containment strategies aimed at reducing risk and enhancing site integrity.