Institute of Geological Sciences

CO2 Sequestration

Modelling of CO2 Sequestration

Our literature study (Chevalier et al. 2010) has identified several deep saline aquifers in the Swiss Molasse Basin, which may potentially be used as reservoirs to store industrial CO2. One of the aquifers considered as a possible injection target is the Trigonodus Dolomite of the Upper Muschelkalk formation. To further evaluate its storage capacity, injectivity and long-term isolation performance, predictive numerical simulations are carried out, constrained by experimental and observational data.

Acidification of the aquifer
Acidification of the aquifer following the dissolution of CO2 into the brine, 5000 years after injection. The aquifer is assumed to have a homogeneous permeability of 1e-15 m2. Note the fingerlike downward movement of the acidic brine.
Regional-scale model of CO2 injection at industrial rates (1 Mio t for 1 year)
Regional-scale model of CO2 injection at industrial rates (1 Mio t for 1 year). This simulation investigates the influence of a 2° dip of the Muschelkalk aquifer on the movement of the CO2 plume. Panel A) The fluid pressure 1.5 years after shut in. Large-scale CO2 injection constitutes a major perturbation of pressure conditions in the aquifer. The induced pressure anomaly is still detectable after tens of years. Panel B) The CO2 plume (as CO2 saturation XCO2) after 2500 years. The plume migrates up-dip due to buoyancy forces and in the absence of groundwater flow. The plume moves at an estimated rate of 0.46 m/yr.