Several hydrocarbon accumulations were discovered between 1975 and 1977 in Block 16/7 in United Kingdom waters along the western edge of the Viking graben. By 1978, 13 exploratory wells were completed, and development planning focused on the southern part of the area.

The southern part of the Brae area is unique compared with other documented North Sea fields. An oil column of about 1,500 ft (457 m) is contained in Upper Jurassic conglomerate and sandstone shed off the Fladen Ground Spur as it was uplifted by faulting and as the Viking graben subsided. This major fault zone places Upper Jurassic against Devonian rocks and is the important seal along the west flank of the field. The cap rock and likely oil source are provided by the Upper Jurassic Kimmeridge Clay, which drapes a low anticline and dips eastward into the basin.

Stratigraphic changes within the reservoir interval are abrupt. The depositional setting is interpreted as coalescing fan deltas spilled into the basin from adjacent uplands. Conglomerate and sandstone were deposited mainly subaerially on fan-delta surfaces, whereas laterally adjacent siltstone was laid down as fringing marine foresets. Complex diagenetic events have overprinted these facies.

Other hydrocarbon accumulations similar in setting to the Brae field undoubtedly await discovery.

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