34/4-15 S

General

Well 34/4-15 S was drilled to test the Dugong prospect west of the Snorre field on Tampen Spur in the North Sea. The primary objective was to prove presence and commercial volumes of movable hydrocarbons in the Jurassic sandstones of the Rannoch Formation. The secondary objective was to prove hydrocarbons in the Late Jurassic Intra Draupne Formation Sandstone.

Operations and results

Wildcat well 34/4-15 S was spudded with the semi-submersible installation Deepsea Yantai on 17 June 2020 and drilled to TD at 3570 m (3455.9 m TVD) m in the Early Jurassic Drake Formation. Operations proceeded without significant problems. The well was drilled with Glydril mud down to 1041 m and with Versatec oil-based mud from 1041 m to TD.

The primary target, Rannoch Formation was penetrated at 3425.50 m (3311.5 m TVD) and contained a 75 m oil column in moderate to good quality reservoir with an ODT at 3501.3 m (3387.3 m TVD). Intra Draupne Formation sandstone was penetrated from 3378.3 to 3386.9 m (3237.1 to 3245.7 m TVD). Petrophysical analysis indicate hydrocarbons in the Intra Draupne sandstones, but no net pay due to poor reservoir properties. Conventional and sidewall cores had oil shows through the Intra-Draupne Formation Sandstone from 3378 m to ca 10 m below ODT in the Rannoch Formation at 3512 m. The shows vary in intensity, but are typically described as "Trace hydrocarbon odour, no oil stain, no direct fluorescence, trace very slow blooming blue-white fluorescent cut, no visible cut, weak dull blue-white fluorescent residue, no visible Residue".

Two cores were cut in the well. Core 1 was cut from 3435.6 to 3466.25 m and core 2 from 3466.25 to 3516.78 m. Two MDT oil samples we