6406/2-9 S

Well 6406/2-9 S was drilled to test the Ragnfrid Nord prospect on the Halten Terrace in the Norwegian Sea. The primary exploration target for the well was to prove petroleum in Middle to Lower Jurassic reservoir rocks (in the Garn and Ile formation and in the Tofte formation, respectively). The secondary exploration target was to prove petroleum in Upper Cretaceous reservoir rocks (the Lange formation) and in the Lower Jurassic (the Tilje formation), in the event of discovery in the overlying Tofte formation.

Operations and results

Wildcat well 6406/2-9 S was spudded with the semi-submersible installation West Phoenix on 3 October 2018 and drilled to TD at 4983 m (4919 m TVD) in the Early Jurassic Tilje Formation. The well was drilled with seawater and hi-vis pills down to 1515 m, with Innovert oil-based mud from 1515 m to 3429 m, and with non-aqueous BaraECD mud from 3429 m to TD.

In the primary exploration target, the well encountered a gas/condensate column of about 10 metres in the Tofte formation with moderate reservoir properties. A gas-water contact was assessed at 4737 m (4689 m TVD) and oil shows (direct fluorescence and visible cut) continued throughout the cored section to 4764 m. The entire Tofte formation totals about 140 metres, of which 120 m sandstone of poor to moderate reservoir quality are effective reservoir rocks. The cores documented a deformation/fault zone in the upper part of Tofte. The Garn and Ile formations had about 75 and 65 metres effective reservoir rock respectively, mainly with poor to moderate reservoir quality. Both formations are water bearing. In the secondary exploration target in the Lange formation, the well encountered several one to five-metre thick gas-bearing sandstone layers with poor reservoir quality in the interval 4266 to 4306 m. The uppermost