Review Of Canadian Arctic Resource Activities (1987)

Abstract Exploratory activities in the Canadian Arctic regions started in the early 1960s. Major emphasis had been on exploratory drilling in the Mackenzie Delta/Beaufort Sea area, while there were some modest activities in the Labrador Coast, Hudson's Bay and the Arctic Islands. This paper gives an overview of the past activities in the Canadian Arctic in the resource sector. It describes the major drilling technology developments undertaken by Canadian industry in order to operate under harsh Arctic environments. Two development examples are described to illustrate the innovations in production concepts required to bring the potential reserves onstream from the Arctic region. Introduction Canada's Arctic encompasses the four major geographic areas (Fig. 1): the Labrador Coast, the Arctic Islands, the Hudson's Bayand the Beaufort/Mackenzie Delta. For the past two decades, the search for hydrocarbons has been concentrated in the Arctic Islands and Beaufort region, with some drilling in the Hudson's Bay and the Labrador Coast. The two areas that have seen substantial exploratory activity have indicated high potential accumulations of both oil and gas. Drilling Technology Development The harsh physical environment in the high Arctic has necessitated the development of new and innovative technology. A proliferation of new drilling techniques and hardware attest to industry's continuing efforts to cope with this unique environment. The Arctic Islands are ice-covered for most of the year. Some thawing may occur, but there is rarely an ice-free period. Due to the presence of numerous islands, the ice sheets are anchored and relatively stable. This has permitted the use of a unique drilling system, the "Ice Platform Rig ". The concept was initiated in 1974, when the first offshore well was drilled from a platform with a land rig in 421 feet of water. Subsequently, two prototype rigs were designed and constructed by Panarctic Oils Ltd. to drill in deeper water and to greater depths. The basic concept is simple and it s based on the premise of utilizing nature's creation, ice cover. To support the weight of a drilling rig, an ice pad is designed and built by flooding the ice with water until a predetermined ice thickness is achieved. A purpose-built rig, having the derrick capacity to handle a full-sized BOP stack, is then installed, and drilling is carried out through a moonpool system (an arrangement for drilling several wells from the same site). The concept was improved by devising ways of extending the drilling season – such as by using foam insulation to reduce the thickness of the ice pad and therefore the construction time. The technology improvements achieved in the Beaufort Sea have been dramatic. The first exploratory well in this region was drilled from a man-made gravel island in shallow water. The island was constructed using gravel dumped through an opening in the ice — a technique possible only in the land-fast ice zone near to shore. As exploration moved further offshore into deeper water and into areas where ice is constantly moving, drilling technology required became more complex.