15/8-2

General

The 15/8-2 well was drilled in the Ve sub-basin, west of the Sleipner Field and ca 3 km from the UK border in the North Sea. The primary objective was to prove a commercial hydrocarbon accumulation within Upper and Lower Hugin Formation. The secondary objectives were to test possible hydrocarbon presence within the Sleipner Formation and leads in the Hod Formation (Goldfinger lead) and Late Jurassic.

Operations and results

Well 15/8-2 was spudded with the semi-submersible installation COSLPioneer on 20 August 2011 and drilled to TD at 4386 m in the Middle Jurassic Sleipner Formation. Before spud, a shallow gas class 1 warning was given. A 9 7/8" pilot hole was drilled from 208.5 to 1100 m. However, no shallow gas was observed by the ROV at the wellhead or by the MWD during drilling. No significant problem was encountered in the operations. The well was drilled with Seawater and bentonite hi-vis sweeps down to 1133 m, with Glydril mud from 1133 m to 2419 m, and with Versatec OBM from 2419 m to TD.

The well penetrated rocks of Quaternary, Tertiary, Cretaceous, and Jurassic age. No hydrocarbon indications were observed in the Hod Formation (Goldfinger) and only thin sandstone stringers were observed in the Late Jurassic. The main target Upper Hugin Formation was encountered at 3881.5 m, 31 m higher than prognosed, and the Lower Hugin Formation came in at 4065 m, 1 m shallower than prognosed. The secondary target Sleipner Formation was encountered at 4238 m, i.e. 61 m deeper than prognosed. No movable hydrocarbons were proven in the well.

Shows: Bright yellowish direct fluorescence, and a slow streaming cloudy bluish white cut fluorescence was recorded in siltstones in the Dra