ID: 600
OBJECTID: 600
wlbNpdidWellbore: 1131
wlbName: 25/5-1 A
wlbHistory:

General

Appraisal well 25/5-1 A was drilled as a sidetrack to well 25/5-1. The wells are located in the Northern part of block 25/5 near the crest of a westward tilted Jurassic fault structure that straddles both block 25/5 and block 25/2.

The main purpose of the well was to prove additional accumulation and if possible determine an oil/water contact that might be compared with well 25/5-1. Also checking a possible spill point through the main fault mapped 4 km SSW of well 25/5-1.

Operations and results

Appraisal well 25/5-1A was spudded by Golar-Nor offshore a/s semi-submersible installation Nordtrym 1 August 1987, and completed 16 September 1987 at a depth of 3432 in the Early Jurassic Drake Formation. The Vestland Group came in at 3312 m (3050.9 m TVD MSL), 91.9 m TVD deeper than in 25/5-1 but with the same thickness as in 25/5-1. Top Dunlin Group / Drake Formation came in at 3403 m (3126.7 m TVD MSL). The whole reservoir was oil-saturated, confirming oil down to at least 3126.4 m TVD MSL, very close to the OWC that was estimated from the 25/5-1 pressure gradient data. However, a definite OWC was not observed. All in all the well supported a total vertical oil column of 166 m as estimated from well 25/5-1. The well was plugged and abandoned as an oil appraisal well.

Testing

No drill stem test was performed.

wlbHistoryDateUpdated: 2018-03-16T00:00:00