Coupled Reservoir-Geomechanical Modeling and Stability Analysis during CO₂ Injection into Minjur Sandstone Reservoir

The continuous emission of carbon dioxide to the environment has caused major climatic changes and is the main cause of the global warming. In order to mitigate the level of carbon dioxide in the atmosphere, the excess amount of carbon dioxide needs to be permanently stored in the deep sedimentary rocks. The pore pressure buildup during carbon dioxide injection process needs to be monitored in order to prevent the failure of the reservoir and hence the leakage of the stored carbon dioxide. In this paper, coupled geomechanical modeling and stability analysis are performed for the Minjur Sandstone reservoir in Saudi Arabia. The pore pressure buildup and ground uplift was calculated during carbon dioxide injection into the reservoir. The Mohr-Coulomb failure criterion was utilized to perform the stability analysis of the reservoir. The stability analysis was performed for the reservoir which suggested safe carbon dioxide injection parameters based on the changes in the pore pressure and horizontal stresses in the reservoir.