4D Feasibility Study of a Carbon Storage Project in Bredasdorp Basin, South Africa

Summary A 4D feasibility of a carbon storage project was performed in the Bredasdorp Basin. A 4D geomechanical model was carried out by integrating geophysical logs, a 1D geomechanical model, and 3D seismic lines. A 3D static model was first developed using 3D seismic lines and geophysical logs from eight exploration wells. Following the static model, the relative permeability, gas-water contact (GWC), and PVT were imported into the static model to create the dynamic model. A 3D geomechanical grid was constructed and populated with the 1D geomechanical model created from geophysical logs. A 3D model of elastic properties was generated. A stress gradient of 0.016 MPa/m for the minimum stress and 0.018 MPa/m for the maximum stress estimated from drilling data was used as boundary conditions in the 3D geomechanical model. A couple of dynamic and geomechanics simulations were developed to investigate the risk posed by 40 years of carbon injection. It was found that the reservoir remains stable.