ICE ISSUES RELATING TO THE KASHAGAN PHASE II DEVELOPMENT, NORTH CASPIAN SEA

摘要

The Kashagan field in the North Caspian Sea was discovered in 2000. It is a world class deposit and is estimated to contain 9 billion to 16 billion barrels of recoverable oil equivalent and has been under development since its discovery. The ice conditions in the North Caspian Sea are not severe by comparison with the Arctic, however there are some unique challenges. At 80 km offshore, the water depth at Kashagan is only between 4 and 8 m. This can lead to significant grounded ice features which affect both platform access and escape, and sea floor facilities, such as pipelines. The shallow water favours the use of low freeboard islands which can then be susceptible to ice encroachment. Water ballasted drilling barges and ice barriers, which are also used, require determination of global and local loads for optimum design. Since its discovery, a considerable amount of research on data gathering on the ice environment and ice design criteria relating to the above issues has been conducted: most recently in the context of Phase 2 of the development. The intent of this paper is to give an overall summary of the ice environment as well as the ice issues for design and operations.