7316/5-1

General

Wildcat well 7316/5-1 is located in the Vestbakken Volcanic Province of Bjørnøya West area. The well is located about 150 km south Southwest of Bjørnøya, and about 150 km North-west of well 7219/9-1 which was used for correlation purposes.

The Primary objective of the well was the potential of Tertiary prospects at lower Oligocene and upper Eocene levels. A secondary objective was to undertake a sampling and coring programme to provide improved stratigraphical control in the area.

Operations and results

Well 7316/5-1 was spudded with the semi submersible installation Polar Pioneer 21 July 1992 and drilled to TD at 4027 m in the Late Cretaceous Nygrunnen Group. The first hole was drilled to 906 m where it had to be plugged and abandoned due to gas influx and lost circulation. The rig was moved 43.4 m and the well was re-spudded on 5 August. On the second attempt, an 8-1/2" pilot hole was drilled to 613 m. A drilling break with associated gas production was observed at 606 m and a cement plug was set over the interval 540 m to 597 m. The well was drilled with spud mud down to 921 m, with KCl / PHPA polymer mud from 921 m to 3800 m. From 3800 m to TD KCl was allowed to deplete naturally and the system was slowly converted to a higher temperature stable mud.

The Uppermost Sandstone of the Eocene Sotbakken Group B2 Member was encountered from 1340 m to 1383 m, and was considered to be gas bearing over the interval 1340 -1358.5 m. From a gross thickness of 43.0 m, a total net pay thickness of 9.75 m was calculated, giving a net/gross ratio of 0.23. Average porosity of 28.2% and average Sw of 35.9% was computed in the pay zone. A second sandstone was encountered from 1442 m to 1469 m in the Sotbakken Group B2 Member. Gross thickness of this Sand was 27.0 m, with average porosity of 32,1 %. It proved to be entirely water wet.

Numerous igneous intrusions were penetrated below 2976 m (Middle to Earl