Increased oil prices have renewed interest in the arctic especially in view of the large potential reserves expected to be found there. In fact, the National Geological Society estimates that approximately one-third of all remaining reserves are expected to be found in the arctic. The legacy of designs for offshore structures in conditions were they have had to contend with ice forces in addition to waves, wind and currents shows that the earliest designs are based on fixed platforms and were deployed in relatively shallow water. These include designs which are based on grounded barges mounted on a prepared seabed section. More recent designs are based ship shaped FPSO’s which have a disconnectable inboard weather vaning turret. Under the threat of ice forces, which the vessel is not designed to withstand, the hull is disconnected from the mooring turret.
During the last decade there have been a number of significant developments in deepwater floater technology increasing the production water depth from about 4,000 ft to 8,000 ft. Designers are now considering ways to adapt this deepwater floater technology to arctic conditions even in situations where the water is not considered, by definition, to be deep water.
The presentation is an overview of design considerations for offshore floaters in the arctic. It discusses how the added environment of ice affects these designs and discusses some engineering solutions.