Interaction of CO2 and Cap Rock

Current proposals to reduce atmospheric emissions of anthropogenic greenhouse gases often include the capture of carbon dioxide and subsequent injection into deep subsurface formations. Prior to large-scale deployment of the technique, there are several issues that should be addressed. Leakage into the atmosphere is considered the most crucial concern for geological storage of CO2. Leakage routes could develop through existing wells and pipelines but also by natural migration of CO2 rich pore-fluid through the cap rock and in fault zones. Chemical interaction between the pore fluid and the cap rock may change the material properties of the cap rock. In our study a new experimental setup is tested in order to increase our understanding of the interaction of CO2 with cap rock, with focus on changes in geomechanical and acoustic properties of the rock.