Delineation of the “Zagato” oil discovery in the Barents Sea – 7122/8-4 S

The well was drilled just north of the Goliat field, 90 kilometres from Hammerfest.

The discovery, which was made in production licence 229, is estimated at between 2.8 and 10.1 million standard cubic metres of recoverable oil equivalent (Sm3 o.e.). This corresponds to between 18 and 64 million barrels.

The licensees are considering tying the discovery back to existing infrastructure on the Goliat field.

Exploration well 7122/8-4 S is the 13th well drilled in the production licence, which was awarded in the Barents Sea Project in 1997.

The well was drilled by the COSL Prospector rig.

Geological information

The discovery was proven in Lower Jurassic/Upper Triassic reservoir rocks in the Realgrunnen Subgroup and in Middle Triassic reservoir rocks in the Kobbe Formation earlier this year. Before well 7122/8-4 S was drilled, the operator's resource estimate for the discovery was between 2.4 and 9.7 million Sm3 of recoverable oil equivalent (o.e.).

The objective of the well was to delineate the 7122/8-3 S (Zagato) discovery in Lower Jurassic-Upper Triassic and in Middle Triassic reservoir rocks in the Realgrunnen Subgroup and the Kobbe Formation, respectively.

Well 7122/8-4 S encountered an 11-metre oil column in the Tubåen Formation in the Realgrunnen Subgroup in reservoir rocks totalling 8.5 metres with good reservoir quality. The oil/water contact was encountered 1523 meters below sea level.

Additional reservoir rocks were encountered in the Kobbe Formation totalling 48 metres with moderate reservoir quality, but the reservoirs were aquiferous.

An 80-metre oil column was also proven in the Klappmyss Formation in sandstone layers totalling 1 metre with poor reservoir quality. The oil/water contact was not encountered.

The well was not formation-tested, but extensive data acquisition and sampling were carried out.

Appraisal well 7122/8-4 S was drilled to respective measured/vertical depths of 2986/2793 metres below sea level, and was terminated in the Klappmyss Formation in the Lower Triassic.

Water depth at the site is 406 metres, and the well has been permanently plugged and abandoned.