7321/7-1

General

Well 7321/7-1 was the first well drilled on the license. It is located in the Fingerdjupet Sub-basin in the Bjørnøya Øst area. The primary objective of the well was Jurassic to Triassic sandstones in a rotated fault block. Potential was expected throughout the Middle Jurassic to Base Carnian interval.

Operations and results

Wildcat well 7321/7-1 was spudded with the semi-submersible installation Ross Rig 26 June 1988 at a depth of 3550 m in Early Triassic rocks. The hole was drilled to 526 m and then abandoned due to building up of the angle. The rig was moved 13 m and the well was re-spudded 27 June 1988. The hole was drilled to setting depth for 20" casing without returns to the surface. During drilling of 17 1/2" hole section, problems with loss of drilling mud to believed weak/fractured formation occurred. This lead to setting of 13 3/8" casing shoe at 1430 m, 770 m higher than planned. The problem with loss of mud continued below 13 3/8" casing shoe and down to 1813 m where the loss was considerably reduced. During drilling of the Jurassic and Triassic sequences no drilling mud was lost to the formation. Except from two fishing operations no significant drilling problems were experienced. The well was drilled with seawater and hi-vis pills down to 982 m and with gelled seawater / polymer from 982 m to TD. There was no shallow gas in the hole.

Top reservoir (Stø Formation) was encountered at 1998.5 m, 97.5 m deeper than prognosed. An Intra Carnian reflector prognosed at 2736 m and was encountered at 2751 m, only 15 m deeper than prognosed. Near bottom a Carnian seismic reflector was encountered at 3448 m. The mud log and wire line logs indicated good reservoir parameters for a gas sand in the interval 2384.8 m to 2390.4 m in the Snadd Formation. Log analysis showed good porosity and low water saturation, 21.2% and 31.1% respectively. Core analysis indicated clean sand with high porosity. Core perme