Geomechanical and Geochemical Considerations for Geologic Storage of Carbon Dioxide in the Utsira Formation, Sleipner

Summary The Sleipner project, located in the Norwegian North Sea, represents the world’s first large-scale CO2 sequestration initiative in a deep saline aquifer. Since its inception in 1996, Sleipner has served as a global benchmark for CCS research, demonstrating the feasibility of safely storing CO2 in high-permeability sandstone formations. In this study, a fully coupled fluid flow and geomechanical approach is used to construct a high-resolution and heterogeneous saline aquifer model, the Utsira Formation. Four main trapping mechanisms are modeled, which are structural/ stratigraphic, residual, solubility, and mineral trappings. An integrated workflow is constructed to create multi-realization models by incorporating uncertainty in geology, geomechanics, and reservoir rock and fluid properties. The objective is to assess how spatial variations in reservoir quality, geochemical interactions, and geomechanical responses influence CO2 migration and trapping mechanisms.