document: On 3 December 2019 Equinor spudded exploration well 15/3-12 S on the Sigrun East prospect. The well location is approximately 4 km southeast of Sigrun discovery well 15/3-4. 15/3-12 S is located in PL 025 but it was drilled sole risk between Equinor and Neptune, using the âWest Phoenixâ S/S. TD was reached at 3,810 m (3,652 m TVDSS) in the Middle Jurassic Sleipner Formation. Three oil-bearing sandstones (9 m, 4 m, and 9 m) were proven in the Middle Jurassic Hugin Formation (which itself was 100 m thick) with no OWC. Estimated recoverable reserves are 7-17 MMboe. On 21 January 2020 sidetrack 15/3-12 A was kicked-off. This well was drilled because the main wellbore was not sited in an optimal position to test the secondary Upper Jurassic Draupne target. Equinor had drilled the 12-1/4" hole to section TD at 3,593 m (3,427 m TVD) and had started logging, but then ran into issues which led to a technical sidetrack (T2) being kicked-off in early February 2020. This well was drilled to TD at 4,037 m (3,796 m TVD) in the Sleipner Formation. Both the Draupne (85 m) and the Hugin (120 m) formations were present but they were water-wet. There were some oil shows in a thin 3 m sandstone in the Sleipner Formation but the well is classified as a dry hole. Development of the Sigrun East discovery is being considered as a tie-back to Gudrun. On 2 March 2020 the well was being abandoned.  The Sigrun discovery was made by Elf Petroleum in 1982. 25/3-4 proved oil and gas at four levels in the Hugin and Sleipner formations with different pressure regimes. A test in the Hugin Formation flowed at a rate of 3,868 bo/d plus 8.65 MMcfg/d through a 40/64â choke. A downdip appraisal well was drilled in 1983 / 1984 which established an OWC at 4,023 m. The Hugin Formation was absent and the Sleipner Formation consisted of thin sandstones with a net pay of less than 7 m.   In 2018 Equinor drilled appraisal well 15/3-11 which confirmed a 35 m oil column (15 m of sandstone) in the Hugin Formation with no OWC. As a result of this well, Equinor increased the estimated recoverable reserves range from 2-9 MMboe to 7-13 MMboe and a development using the Gudrun facilities is being considered.  Equinor Energy AS operated the Sigrun East well with a 75% interest. It was partnered by Neptune Energy Norge AS (25%).
summary: 015/03-12 S,A (Sigrun East) (Equinor 36% op. Neptune 25%, OMV 24%, Repsol 15%) in PL 025 block 9,4 + 9m oil reservoirs in the target Middle Jurassic Hugin Fm, total 100m of moderate quality, no OWC. Sidetrack (A) targets U. Jurassic Draupne + Hugin found water-wet. Est. 6-17 MMboe recoverable, tie-into Gudrun to be considered. TD=3810 m.