This research was carried out with the aim of providing a better understanding of the multiphase fluid flow characteristics of fluid-rock systems during the geo-sequestration process. The ultimate goal of this research was to experimentally evaluate the change in a number of multiphase flow characteristics of the system over time caused by the potential chemical and physical/mechanical processes occurring during deep CO2 disposal. In order to achieve this goal the effects of cyclic/alternating CO2-brine flooding, flow direction, existence of residual hydrocarbon (natural gas) and change in the reservoir stress field on the system’s multiphase flow behaviour were investigated.