Assessing the geomechanical modelling of underground reservoir for CO₂ storage trapping mechanisms

Effective carbon dioxide (CO₂) storage is essential for mitigating climate change amid increasing global greenhouse gas emissions. This study investigates the influence of geomechanics on CO₂ storage performance within carbon capture and storage (CCS), focusing on structural, residual, and solubility trapping mechanisms using a fully coupled modeling framework. Two numerical models, with and without geomechanical effects, are developed to evaluate impacts on reservoir behavior, CO₂ migration, and trapping efficiency. Each mechanism is analyzed separately and within an integrated framework to assess their combined contributions. Results indicate that geomechanical coupling increases reservoir pressure, reduces CO₂ flow velocity, enhances migration control, and produces slightly higher relative permeability with a slower temporal decline. After 500 years, residual trapping accounts for 46.63% of stored CO₂ with geomechanics compared to 49.39% without, while solubility trapping contributes 18.20% and 18.28%, respectively. Structural trapping represents 35.17% of mobile CO₂ with geomechanics versus 32.33% without. Residual trapping remains the dominant mechanism in both scenarios. Overall, the findings highlight the important role of geomechanics in controlling reservoir properties, CO₂ migration, and long-term storage security, supporting its inclusion in CCS design to optimize storage efficiency and reliability.