Smorbukk field, discovered in 1984, is situated approximately 230 km west of the Norwegian mainland where the water depth is 250 to 300 m. The field lies at the crest of a southeast-dipping fault block, bounded on the west by a major normal fault and on the north by an east-west-trending graben that transects the crest of the fault block. Hydrocarbons are contained in four Lower to Middle Jurassic sandstone formations deposited in tidally influenced nearshore and braid delta front environments. Multiple reservoir zones with various hydrocarbon contacts and gas-oil ratios are separated by transgressive shale units that form vertical pressure barriers. The fluids are mainly rich gas condensates (GOR, 1500 to 1800 standard m³/standard m³), but volatile il (GOR, 470) is present in one zone.

Permeability varies as a function of facies-dependent primary sand quality and depth-dependent diagenetic alteration. The sandstones are heavily quartz cemented and extensively illitized, reflecting their present maximum burial depth of 3800 to 4400 m MSL. In the better zones, however, sufficient primary intergranular macroporosity survives to give core permeability measurements ranging from 10 to 1000 md.

Total in-place reserves are estimated to be 106 billion standard m³ (3.7 tcf) of gas and 90 million standard m³ (566 million bbl) of condensate/oil. However, only three wells have been drilled in the field, and further appraisal drilling is needed to confirm these estimates. Simulation studies have not yet been carried far enough to provide realistic estimates of total recoverable reserves.

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