16/10-5

General

Well 16/10-5 was drilled on the Isbjørn prospect in the northern end of the Jæren High in the North Sea. The Isbjørn Prospect was mapped as a four-way dip-closure structure. The primary objective of the well was to test the hydrocarbon potential in the Late Jurassic Ula Formation sandstones.

Operations and results

Well 16/10-5 was spudded with the jack-up installation Mærsk Giant on 6 October 2012 and drilled to TD at 3034 m in the Middle Jurassic Bryne Formation. A 12 1/2” pilot hole was drilled from below the 30” conductor to 1057 m to check for shallow gas. No shallow gas was seen. Drilling of the 8-1/2” section was troubled with junk in the hole ending up with two additional clean-out runs; else, operations proceeded without significant problem. The well was drilled with seawater and sweeps down to 180 m, with KCl/GEM/Polymer mud from 180 m to 1057 m, and with Enviromul oil based mud from 1057 m to TD.

The well penetrated 98 m of radioactive Mandal Formation shales directly overlying the Ula Formation. The Ula formation came in at 2929 m, which was 65 m shallower than the prognosis. One hundred and six m of good quality sand was penetrated but it was water filled without shows and gas values were low. RCI pressure data points indicate a common formation water gradient, with no likely internal pressure barriers, for both Ula and Bryne Formations.

No conventional or sidewall cores were taken. The RCI tool was run for pressure points, but no fluid samples were taken. Maximum static temperatures was measured in the reservoir on wireline RCI run was 124 ºC at 3039 m.

The well was permanently abandoned on 27 November 2012 as