Exploration for Cretaceous stratigraphic traps in the Gulf of Guinea, West Africa and the discovery of the Jubilee Field: a play opening discovery in the Tano Basin, Offshore Ghana

The discovery of the Jubilee Oil Field in 2007 in the Tano Basin of Ghana is a primary example of the potential for Late Cretaceous deep-water stratigraphic traps in basins previously overlooked by the exploration industry. The Tano Basin forms the eastern extension of the Deep Ivorian Basin, which resulted from Aptian–Albian trans-tension associated with the opening of the Atlantic between the St Paul and Romanche fracture zones and the subsequent post-rift subsidence. The basin was the focus for deposition of a thick Upper Cretaceous, deep-water clastic sequence, which, in combination with a modest Tertiary section, provided sufficient thickness to mature a Cretaceous source rock in the central part of the Tano Basin. This well-defined reservoir and charge fairway forms the play, which, when draped over a large plunging nose (the South Tano high), resulted in the formation of a stratigraphic–structural combination trapping geometry that is characteristic of the Jubilee Field and subsequent discoveries in this play.