This project will compile relevant properties from national and international reservoirs with highly variable lithologies, formation water compositions, temperatures and rock/water-ratios (porosity), which are currently assessed for their CO2 storage prospectivity. The data will be used to determine the evolution of fluid-rock reactions and the respective formation water composition over time through reaction path modelling. We expect to identify characteristic trends and water quality indicators for particular reservoir conditions. The latter could be used for the development of monitoring plans. Our studies will also estimate the capacity to permanently immobilise CO2 through mineral (carbonate) precipitation.