Carbon capture and storage operations (CCS), also known as sequestration, is now a widespread practice and a viable path for reducing atmospheric carbon dioxide (CO2) concentrations with implication on climate change and global warming. Successful sequestration of CO2 in deep formations (called sinks) 800 metres or more below ground provides a permanent storage solution for anthropogenic CO2 emitted from large industrial sources (e.g. cement factories, waste incinerators or coal-fired plants, see figure 1). CO2 sequestration is vital for ensuring environmental sustainability by cutting down on greenhouse gas emissions. Potential subsurface storage targets for CO2 sequestration encompass depleted hydrocarbon reservoirs, aquifers (saline formations), un-mineable coal seams, organic-rich shales and basaltic formations.
In Switzerland, despite the promising theoretical storage capacity potential of 2670 million tons of CO2 for the Swiss Molasse Basin (Chevalier et al., 2010), the possibility for suitable large-scale underground storage for CO2 still needs to be assessed accurately. A major challenge is an accurate regional screening leading to the identification of candidate sites suitable for pilot-scale or commercial-scale storage of CO2 in Switzerland. Especially, the scarcity or lack of available or reliable geological data hamper this challenge even more. Another challenging issue is the vertical and lateral subsurface geological complexity and heterogeneity. Despite those challenges, the scientists will carry out a site screening activity under the context of the ELEGANCY project to identify potential areas suitable for underground CO2 storage in Switzerland.