The Ninian field is a giant oilfield located in the UK Sector of the North Sea. The field, which had an initial oil in place (STOOIP) of some 2,588 MMSTB, has been on production since 1978. Waterflooding commenced early in the life of the field because, like other Brent Formation fields in the North Sea, Ninian has a highly undersaturated oil and limited aquifer support. In October 1994, the field's cumulative oil production reached the one billion barrel milestone. The projected ultimate oil recovery ranges from 1,120–1,255 MMSTB.
This paper presents the reservoir management philosophy and operating practices at Ninian. It discusses the geology and production history of Ninian. The performance of the waterflood is reviewed. The field development strategy, the effect of reservoir heterogeneity and the steps that are and have been taken to improve areal and vertical sweep efficiency are discussed. The paper then discusses the current and future reservoir management challenges facing a mature oilfield like Ninian and how they will be met A recent re-processing and re-interpretation of the 3D seismic has resulted in new maps for the field and improved definition of the severely eroded and highly faulted East Flank of the field. The paper describes the steps being taken to further develop the East Flank based on the new data.