Deepwater technology. Part 1. Stationkeeping now reliable to 7000 ft plus

Today's drillship mooring and positioning systems can reliably keep the vessel within the necessary positioning limits down to water depths of 6000 ft. Conventional mooring systems are practical to 2000 ft; beyond this depth, dynamic positioning techniques are generally preferred. A technical overview of these two alternatives points out their limitations and the improvements required for operating in water depths over 6000 ft.