The storage of CO2 under supercritical conditions in deep saline aquifers is presently the most studied option of CCS (CO2 Capture and Storage).Another option which is under serious consideration is the trapping of CO2 in deepsea sediments at low temperature,either as a liquid or as a gas hydrate,or both.The storage capacity as gas hydrates depends strongly on the local geothermal gradient as well as the quality of the CO2 stream after the capture process.