Ice management using icebreakers to reduce floe size ahead of a stationary drilling vessel will be a key component of offshore Arctic exploration and development drilling. Selection of the management vessels and fleet deployment configuration is critical to insure the ability to (1) maintain the drilling vessel within the managed ice channel as ice drift direction continuously changes, and (2) produce sufficiently small floe sizes during periods of high ice drift velocity. This paper describes the key considerations for accomplishing the complex task of ice management and demonstrates a field-calibrated, simulation-based means for testing the efficacy of various tactics against actual measured Beaufort Sea ice drift and thickness time histories collected by the Fisheries and Oceans Canada since 1990. The results provide valuable insight into ice management fleet composition and fleet deployment; for instance, it is shown more efficient to use a racetrack versus circular icebreaker track to maintain an ice channel for the stationary drillship.
With a flurry of recent exploration license awards and more on the horizon, the challenge of drilling deep water, high-Arctic exploration wells amid summer season sea ice cover stands immediately in front of our industry. Due to the unpredictable and often very short open water windows, the capability for floating drilling vessels to keep station in drifting ice is needed so that exploration wells can be confidently undertaken and completed in a practical number of seasons. Hence ice management has more of an economic driver as safety of the drillship is never in question. The challenge lies in designing an ice management fleet and deployment configuration that can maintain the drilling vessel within the managed ice channel as ice drift direction continuously changes, and simultaneously produce sufficiently small floe sizes during periods of high ice drift velocity.
