Numerical modeling of the geomechanical behavior of biyadh reservoir undergoing CO₂ injection

Sequestration of CO₂ in deep sedimentary reservoirs is one of the potential methods that can be used for reducing the level of CO₂ in the atmosphere. In this investigation, a geomechanical modeling study was performed for the deep Biyadh sandstone reservoir in Saudi Arabia. The results clearly demonstrate that the impermeable cap rock restricts the transport of CO₂ from the reservoir to the overburden layers. For a 10-year period of CO₂ injection, the simulation results show a ground surface upward displacement that spread over several kilometers around the injection site. It was also observed that the storage capacity of CO₂ increased exponentially as the injection pressure of CO₂ increased. The increase of the pore pressure with the passage of time, during CO₂ injection, altered the stress and displacement fields inside the reservoir. Moreover, the safe values of injection pressure for the reservoir were evaluated for the selected period of injection using Mohr-Coulomb failure criterion.