Petroleum exploration in northern Canada's marine areas will rely on unique new methods to cope with the ice-clad seas. An adaptation of an air cushion vehicle to an offshore drilling vessel capable of moving across the ice is currently being developed. The Arctic Drilling System under development incorporates two specific features; the ability to move the entire drill system to the desired position in either an ice or water environment and the ability to remain in that position during the drilling operation as the surrounding ice sheet moves.
A test program has been conducted on the fresh water ice of the Great Slave Lake, N.W.T. during the winter of 1971 – 1972 with a 178-ton air cushion transporter to evaluate the behavior of the ice and the transporter during traverse of the surface. Instrumentation of the transporter was developed to measure and record all forces and motions of the system to permit numeric simulation for design of a much larger drill system. In support of the testing of the transporter, studies of ice properties at the test site and in the Arctic are being conducted. Other tests in the program include the evaluation of an ice-melt system and propulsion systems.
The test program and evaluation of the data is currently in progress for economic analysis of the Arctic Drilling System. Results of these tests demonstrate the physical ability of an air cushion transporter to move large loads over ice in both the failure and non-failure load condition.
Two prime geologic basins in northern Canada present a major opportunity and challenge to those who choose to explore for hydrocarbons to meet North America's ever increasing energy requirements. The Sverdrup Basin in the eastern Arctic Islands and the Beaufort Sea off the MacKenzie River Delta present a particular challenge to the conduct of exploration activities as both of these remote marine areas are covered by ice several months of each year. Ice conditions vary locally, regionally and seasonally. The characteristics of the ice cover important to the development of an operational system for offshore petroleum exploration are:
With the exception of some ice locked embayments, the ice sheet moves.
Thickness and strength vary throughout the. seasons from open water conditions through "first-year", 6 to 7 feet growth, with ‘multi-year’ thickness of 12 to 15 feet. Ridges, rafting and ‘bergs’ add variety to the conditions.
The polar regions seasonal darkness, severe cold and restricted access contribute to the overall problem of support, manpower and operational safety.
To develop system capable of efficient operation in this environment, Arctic Engineers and Constructors began a program to develop large non-self-propelled air cushion platforms which have the capability of a moveable foundation for well drilling and related equipment. The initial phase of the program was the construction of a 100-ton payload Air Cushion Transporter (ACT-100) in 1971 at Edmonton. Alberta.
