Development Program for Ekofisk Field - Offshore Norway

Abstract The Phillips Group discovered the Ekofisk field on the Norwegian Continental Shelf of the North Sea with the drilling of the Ekofisk IAX late 1969. Three step out wells were drilled for confirmation and further geophysical, geological and reservoir information. Concurrent with the drilling of the later wells, plans were formulated and augmented for the development of the field. The development program consists of a series of phases, each one being a continuation of the previous one, but with each phase having a definitive purpose in itself. Phase I is the test phase wherein the four original Ekofisk wells are produced by sub-sea wellhead equipment, temporary. producing facilities and S.P.M. tanker loading facilities. Its primary purpose is to obtain longer term production history, additional reservoir information and early operational experience. Phase II is the fabrication, erection and installation of permanent drilling and producing facilities. It consists of three drilling platforms, a production platform, compressor equipment for reservoir pressure maintenance, underwater storage and the repiping of loading facilities. Its purpose is the initiation and fulfilment of permanent producing facilities for the early and rapid build-up of production to the fields potential of 300,000 barrels of oil per day. Subsequent phases consist of a gas pipeline, a possible crude oil pipeline, onshore facilities, and the tying in of other fields in the vicinity of the Ekofisk field. A number of problems have been encountered to date with respect to timing and scheduling. The most serious problem has been the weather. Introduction The Phillips Group, comprised of Phillips Petroleum Company Norway, Norske Fina, Norske AGIP and Elf Norge Group, discovered the Ekofisk field in September 1969. The Ekofisk No. lAX topped the Danian Limestone at about 10,000 feet. Continual drilling and accompanying excellent shows revealed an oil saturated section of about 700 feet. Definitive tests were incomplete because of the limited capacity of the test equipment on the rig. Also the weather was so adverse at the time that it would have been extremely hazardous to conduct the extensive testing that was necessary. However, enough information was obtained to indicate that the Phillips Group had an excellent discovery. After this first well, three step out wells were drilled for additional reservoir, geological and geophysical information. These wells confirmed that the first important oil discovery in the North Sea had been made. Figure No.1 was taken during one of the early tests. Present indications are that it is the largest oil field found in Western Europe to date. The Ekofisk field is located on the Norwegian Continental Shelf adjacent to the median line separating Norwegian and U.K. waters.