The Central Brae Field, Blocks 16/07a, 16/07b, UK North Sea
The Central Brae Oilfield is the smallest of three Upper Jurassic fields being developed in UK, Block 16/07a. The field was discovered in 1976 and commenced production in September 1989 through a sub-sea template tied back to the Brae ‘A’ platform in the South Brae Oilfield. The field STOOIP is 244 MMBBLs, and by May 1999 cumulative exports of oil and NGL reached 44 MMBBLs.
The Central Brae reservoir is a proximal submarine fan sequence, comprising dominantly sand-matrix conglomerate and sandstone with minor mudstone units. The sediments were shed eastwards off the Fladen Ground Spur and were deposited as a relatively small and steep fan at the margin of the South Viking Graben. Mudstone facies border the submarine fan deposits to the north and south, forming stratigraphic seals. The structure is a faulted anticline developed during the latest Jurassic and early Cretaceous, initially formed as a hangingwall anticline during extension but subsequently tightened during compressional phases. The western boundary of the field is formed by a sealing fault, whilst to the east, there is an oil-water contact at 13 426 ft TVDss. The overlying seal is the Kimmeridge Clay Formation, which also interdigitates with the coarser facies basinwards and provides the source of the hydrocarbons.