6607/12-2 S

General

Well 6607/12-2 S was drilled on the Alve North structure about eight kilometres west of the Norne field. The primary exploration target for the well was to prove petroleum in Middle and Lower Jurassic reservoir rocks (Fangst and Båt group). The secondary exploration target was to prove petroleum in Cretaceous reservoir rocks (Cromer Knoll group). The Åre Formation should also be evaluated, but the probability of hydrocarbons here was considered low due to a dry Åre Formation in 6507/3-1. The well was designed to be suspended as a possible producer in the event of a discovery. For this reason it was placed as high as possible and in the centre of the structure, deviated and kept parallel to the main fault for keeping a safe distance from potential associated fractures and at the same time access the fluids as efficiently as possible.

Operations and results

Well 6607/12-2 S was spudded with the semi-submersible installation Songa Delta on 22 July and drilled to TD at 4404 m (4274 m TVD) in the Early Jurassic Åre Formation. The well was drilled as high as possible on the NW part of the structure, down to a kick off point above BCU at 3500 m, and then deviated at 30 deg angle in order to stay parallel to the main bounding fault. Drilling the well went without significant problems. A total of 30 days (8 days for Cretaceous and 22 days for Jurassic) was necessary to perform the wire line logging on this well. Three different logging sequences were needed: Cretaceous, Jurassic and Åre deepening to TD. Close to eight days was counted as lost time due to logging problems. The well was drilled with sea water and bentonite hi-vis pills down to 1355 m,