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• Effective CO 2 injection modeling and monitoring are vital for comprehending storage mechanisms and ensuring successful implementation. • Distinctive surface heave results from complex subsurface responses and disconnected damaged zones near KB502 and KB503. • Simulating uplift patterns involves integrating anisotropic permeability and assigning orthotropic materials to damaged zones. This study investigates the ground surface deformation above three injection wells throughout CO 2 injection between mid-2004 to early-2011 in the In Salah CO 2 storage project at Krechba, Algeria. A coupled three-dimensional finite element model of three wells (KB501, KB502, and KB503) was developed. The model accounts for the CO 2 diffusion in the reservoir and structural features including permeable fractures and faults, as well as the poroelastic deformation of the reservoir and overburden layers which result in the ground surface deformations during CO 2 injection. The character of the ground surface deformation above each injection well was different, suggesting a different CO 2 plume shape in the subsurface. An ellipse-shaped heave above KB501 indicates that the CO 2 plume shape followed the anisotropic permeability in the reservoir, KB502's double-lobe surface heave pattern is associated with the activation and pressurization of a vertical fault and finally, the elongated surface uplift pattern above KB503 is linked to the presence of permeable fractured zone in vicinity of the well, as indicated by seismic surveys. The two distinctive structural features in the vicinity of KB502 and KB503 were included in the numerical model, accounting for a hydraulically conductive fault in the caprock and a fractured zone in the reservoir, respectively. The observed surface deformation was utilised to tune the orthotropic mechanical properties of the fault and the fractured zones. The simulation results are in good agreement with the measured InSAR data. In addition, assigning anisotropic permeability to the reservoir plays a significant role in successfully simulating surface uplift patterns. [ABSTRACT FROM AUTHOR]