Abstract
Carbon dioxide is considered to be the greenhouse gas which most contributes to global warming on the earth. Sequestration of CO_2 to geological formations such as aquifers is considered as one of the possible options for the abatement of CO_2 emission to the atmosphere. One of the crucial problems about geological sequestration is the leakage of CO2 from reservoirs. This paper describes numerical research on the mechanism of leakage from the reservoir through the cap-rock. Not absolute permeability of cap-rock but the difference of capillary pressure characteristics between cap-rock and reservoir governs the saturation of sequestered CO_2.
