7321/4-1

General

Well 7321/4-1 was drilled to test the Gråspett prospect in the western part of the Fingerdjupet Basin in the Barents Sea. The primary objective was to prove petroleum in Late Triassic to Middle Jurassic reservoir rocks (Stø Formation) and the secondary objective was to prove petroleum in Late Triassic reservoir rocks (Snadd formation).

Operations and results

Wildcat well 7321/4-1 was spudded with the semi-submersible installation Island Innovator on 25 August 2018. After drilling a 36” top hole to 593 m a 9 7/8” pilot was drilled to 945 m to check for shallow gas. No shallow gas was observed, but the pilot BHA got stuck and had to be left in hole with top at 755 m. A technical side-track (7321/4-1 T2) was kicked off at 745 m and drilling commenced to final TD at 1629 m in the Late Triassic Snadd Formation without significant problems. The well was drilled with seawater and hi-vis sweeps in the 9 7/8” pilot hole and down to 710 m (kick-off for T2 side-track), and with Glydril mud from 710 m to TD.

Well 7321/4-1 encountered about 15 metres of water wet sandstone with poor reservoir quality in the Stø formation. In the Snadd formation, the well encountered about 32 metres of tight and water wet sandstone. Analysis of the mud gas indicated wet gas in the Stø Formation and dry gas in Snadd. Only traces of oil shows were seen. Weak hydrocarbon odour was recorded in a cuttings sample from the Hekkingen Formation, while very weak oil shows (direct and/or cut fluorescence) were described in sidewall cores at 1341.4 m and 1349.7 m in the Stø Formation, and 1417.2 m in the Fruholmen Formation. Organic geochemical analysis of cuttings from the Hekkingen Formation indicate maturity in the late oil window (%Ro ~ 0.8 - 0.9 and Rock-Eval Tma