The Tiffany and Toni oil fields, Upper Jurassic submarine fan reservoirs, South Viking Graben, UK North Sea

The Tiffany and Toni fields lie at the western margin of the South Viking Graben in the Northern North Sea in UK Block 16/17. The reservoirs are composed of coarse clastic sediments of the Upper Jurassic Brae Formation, which were deposited by turbidity currents and debris flows in a submarine fan setting. The Brae Formation accumulated adjacent to the graben margin fault scarp and abuts pre-Jurassic rocks of the Fladen Ground Spur to the west. The Kimmeridge Clay Formation provides both the source of hydrocarbons and the seal for the reservoir.