ID: 365
OBJECTID: 365
wlbNpdidWellbore: 370
wlbName: 25/11-10
wlbHistory:

General

Well 25/11-10 was drilled to appraise the Balder Field on the Utsira High in the North Sea. The objective was to establish the presence of a thick accumulation of oil sand in the southern part of the Balder Field, and evaluate the geologic concept of sand-shale distribution and the reservoir quality of the Paleocene sands.

Operations and results

Appraisal well 25/11-10 was spudded with the semi-submersible installation Glomar Biscay II on 20 January 1981 on and drilled to TD at 1988 m (1985 m logger's depth) in the Danian age chalk of the Ekofisk Formation. The well was drilled with seawater/gel/Lignosulphonate mud.

The Paleocene Heimdal Formation reservoir sands anticipated to be present in this well were found at 1786 m, significantly deeper than prognosed and below the field oil-water contact. Gross thickness of the sands was 128.2 m with an average porosity of 31.4%. They were water wet. The sands were found similar to those found in 25/11-7 to the north. Only thin stringers (2.5 m totally) with shows between 1757 m and 1785 m were found in the Sele and Lista formations.

No cores were cut and no wire line fluid samples were taken.

The well was permanently abandoned on 17 February 1981 as a dry well with shows.

Testing

No drill stem test was performed.

wlbHistoryDateUpdated: 2016-07-06T00:00:00