The Further Development of the Ekofisk Field: "In-Fill" Drilling Taken One Step Further

This paper reviews the planning, preparation and initial implementation of drilling operations for the latest phase of development of Phillips Petroleum's Ekofisk Field in the Norwegian Sector of the North Sea. This development includes the addition of 32 new production and injection wells to the existing ± 80 well field. The unique aspect of the project was that, at the time of conception of the project, only 8 spare slots were available on existing structures, and preliminary economics proved the addition of a new structure unfavorable. The decision to utilize existing structures for the additional wells created many challenges for Phillips Petroleum Norway's engineers and this paper describes a number of the more interesting and unexpected of those challenges and their solutions.