## 7 Conclusions  
This study demonstrates the technical feasibility of using a comprehensive numerical simulation framework that combines fluid flow and geomechanics to model ground deformation caused by CO2 injection for storage. Although the study employed a specific geological model, the conducted sensitivity analysis enables the extension and generalization of the key findings, offering important insights into geomechanical considerations. These findings serve as valuable information for guiding future research and experimentation in this area. The main conclusions derived from this study are outlined below. * Pressure diffusion into adjacent rocks can occur even without significant CO2 migration due to the nature of pressure transmission through pore fluids. This precedes the physical movement of CO2. * The presence of small amounts of CO2 detectable in the surrounding rocks, mainly through diffusion, does not pose a leakage concern in this model, assuming the absence of fractures or other flow localization features. The limited movement of CO2 into the surrounding rocks demonstrates the combined effect of the caprock's low permeability and the high capillary entry pressure, which serve as a robust containment mechanism ensuring the long-term integrity of the geological storage. Further investigation using fine-scale models is recommended to delve deeper into the mechanisms of CO2 entrapment due to diffusion. The use of finer gridblocks in this model can provide a more detailed and accurate representation of the dissolution and diffusion processes. * The study findings indicate that there is persistent ground movement resulting from pressure dissipation, which continues even after the injection period. This validates the use of high-precision instruments, such as floor tiltmeters, for monitoring CCS operations, as they are capable of accurately measuring the displacement rates associated with these activities. * The sensitivity analysis highlights the importance of comprehensive monitoring and robust calibration of these models to effectively manage geomechanical risks associated with CO\({}_{2}\) injection. The findings suggest that rocks with higher Poisson ratios and lower Young's modulus values experience increased vertical displacements. Additionally, higher CO\({}_{2}\) injection rates and reduced shale permeabilities are associated with greater displacement magnitudes. This interplay between rock mechanical properties and operational parameters provides a basis for future research aimed at optimizing CO\({}_{2}\) storage strategies and ensuring the integrity of geological storage sites. Conceptualization, G.S.S., M.V.B.M., M.D., D.V., F.C.V. and K.S. ; methodology, G.S.S. and M.V.B.M. ; software, G.S.S. and M.V.B.M. ; validation, M.D., D.V., F.C.V. and K.S. ; formal analysis, G.S.S., M.V.B.M., M.D., D.V., F.C.V. and K.S. ; investigation, G.S.S., M.V.B.M., M.D., D.V., F.C.V. and K.S. ; resources, M.D., D.V., F.C.V. and K.S. ; data curation, G.S.S. and M.V.B.M. ; writing--original draft preparation, G.S.S., M.V.B.M., M.D., D.V., F.C.V. and K.S. ; writing--review and editing, M.D., D.V., F.C.V. and K.S. ; visualization, G.S.S., M.V.B.M., M.D., D.V., F.C.V. and K.S. ; supervision, M.D., D.V., F.C.V. and K.S. ; project administration, M.D., D.V., F.C.V. and K.S. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable. The data used in this study are provided within the article, and the UNISIM-I geological model is openly available at [[https://www.unisim.cepetro.unicamp.br/benchmarks/en/](https://www.unisim.cepetro.unicamp.br/benchmarks/en/)]([https://www.unisim.cepetro.unicamp.br/benchmarks/en/](https://www.unisim.cepetro.unicamp.br/benchmarks/en/)) (accessed on 12 December 2023). The authors express their gratitude to PETROBRAS for granting permission to use the data and models in this study. The authors [PERSON] and [PERSON] are employed by the company PETROBRAS.