Well 25/1-2 was drilled to appraise the 25/1-1 Frigg Discovery in the North Sea. The primary objective was to test the Eocene Frigg Formation sandstone.

Operations and results

Wildcat well 25/1-2 was spudded with the semi-submersible installation Pentagone 81 on 22 July 1971 and drilled to 1159 m where the tool stuck. The well was then sidetracked from 719 m and drilled to TD at 2772 m in the Late Cretaceous Shetland Group. The well was drilled with a water-LFC mud system.

The Frigg Formation sandstone was encountered at 1948 m. The Frigg sandstones were gas filled down to the gas/oil contact at 1974 and oil filled to the oil/water contact at 1983 m. Thin sandstones and sandstone stringers in the interval 2441 to 2513 m had good oil shows.

No cores were cut. FIT fluid samples were taken at 1984 m (oil and gas), 1986.3 m (oil, filtrate and gas), 1993.5 m (oil, filtrate and gas), 2503 m (filtrate and trace oil), and 2508.5 m (filtrate and trace oil),

The well was permanently abandoned on 25 August as an oil and gas appraisal well.

Testing

No drill stem test was performed.