The hydrocarbon discoveries of the Mid-Norway shelf are very unevenly distributed. All discoveries have so far been made between 64° and 65°30'N and 6°40' and S"E. The Late Tertiary down-to-the-west rotation of the shelf, south of the Nordland Ridge, created distinct zones parallel to the coast where the Upper Jurassic sediments have presently reached oil maturity. Oil generated before the rotation was redistributed and displaced by these movements. The lateral extent of mature source rock reaches a maximum on Haltenbanken, and a minimum west of the Frøya High and west of the Nordland Ridge where huge closely spaced Cretaceous fanlts create narrow border binge zones between the immature high areas to the east and the overmature basins to the west. A regional Jack of hydrocarbon retention over the Nordland Ridge may be due to a thin (or absent) Cretaceous cover in combination with Tertiary reactivation of older faults. On Haltenbanken, obstacles to migration and 'funne!' -shaped migration paths can be defined. Beyond the area of mature Jurassic source on the Platform edge, only the ftanks of basement highs in the V øring Basin are thought to hold any exploration potential.
Mid-Norway shelf - hydrocarbon habitat in relation to tectonic elements