ID: 204
OBJECTID: 204
wlbNpdidWellbore: 208
wlbName: 31/2-4
wlbHistory:

General

Well 31/2-4 is located some 10 km NNW of the discovery well 31/2-1 in a separate fault compartment near the crest of the Jurassic gas accumulation. This crestal area appeared also to coincide with the culminations of all deeper horizons that could be mapped. The well had two main objectives. The first was to appraise the Jurassic gas accumulation in the 31/2-1 Troll Discovery in a location with nearly maximum gross hydrocarbon column. The well should test lateral variations in this reservoir. The second major objective was to explore deeper Triassic/Palaeozoic Formations. The well would test possible hydrocarbon accumulations under the Late Jurassic Troll reservoir, explore possible pre-Jurassic source rocks, and provide geological ages for deep horizons and thus improve the regional geological setting.

TD of the well was proposed to be 5000 m below sea level or in Palaeozoic formations whatever came first.

Operations and results

Well 31/2-4 was spudded with the semi-submersible installation Borgny Dolphin on 1 September 1980 and drilled to TD at 815 m in the Hordaland Group. The well was drilled with seawater and hi-vis pills. After having set the 20" casing, the well was secured and suspended on September 13 due to a farm out of the rig to Statoil. Statoil had requested the Borgny Dolphin to be released to secure their well 34/10-10, which was blowing gas from a shallow gas zone.

The well was classified as a dry well.

Testing

No drill stem test was performed in the well.

wlbHistoryDateUpdated: 2016-05-19T00:00:00