7219/12-2 S

General

Well 7219/12-2 S was drilled to test the Hufsa prospect on the western margin of the Polhem sub-platform in the Barents Sea. The primary exploration target for wildcat well 7219/12-2 S was to prove petroleum in Early Jurassic reservoir rocks (Nordmela formation). The secondary exploration target was to prove petroleum in Late Triassic/Early Jurassic reservoir rocks (Tubåen formation).

Operations and results

Wildcat well 7219/12-2 S was spudded with the semi-submersible installation Leiv Eiriksson on 8 October 2017 and drilled to TD at 2100 m (1854 m TVD) m in the Late Triassic Fruholmen Formation. Operations proceeded without significant problems. The well was drilled with seawater and hi-vis pills down to 430 m, with KCl/polymer/GEM mud from 430 to 1506 m, and with Performadril mud with glycol from 1506 m to TD.

Top Nordmela Formation came in at 1553 m (1480.4 m TVD) and top Tubåen Formation at 1843 m (1678 m TVD). The Nordmela Formation contained a gas column of 23 m of which about 20 m were in sandstone layers with good to moderate reservoir quality. A well-defined gas-water contact was established at 1587.5 m (1503.5 m TVD). The secondary target Tubåen Formation had good reservoir quality but was water wet. No shows are described above top Nordmela. Below the GWC weak spotty shows (dull yellow direct fluorescence, very slow blooming white cut fluorescence and weak fluorescent residue) were described in sandstones down to 1842 m.

Two cores were cut. Core 1 was cut from 1555 to 1578 m with 98.9% recovery. Core 2 was cut from 1578 to 1632 m with 50.7% recovery. The core-depth shifts were +1.87 and +1.71 m for core 1 and core 2, respectively. MDT fluid samples were taken at 15