ID: 596
OBJECTID: 596
wlbNpdidWellbore: 1071
wlbName: 6507/7-8
wlbHistory:

General

Well 6507/7-8 is a replacement well for well 6507/7-7 and was drilled on the southern flank of the Heidrun Field on the Halten Terrace. The primary objective was to appraise reserves in this part of the field. Further objectives were to obtain a water sample from the Aldra (Tilje) Formation, evaluate vertical communication between sandstone units in the Tomma Formation (Fangst Group), and to obtain oriented cores from this section for fracture orientation studies.

Operations and results

Appraisal well 6507/7-8 was spudded with the semi-submersible installation Treasure Hunter on 9 June 1987 and drilled to TD at 2855 m in Early Jurassic sediments of the Åre Formation. Some problems with low penetration rate and bit balling occurred in the 17 1/2" section in swelling clay, sometimes interbedded with pebbles. The well was drilled with seawater and gel sweeps down to 1035 m and with KCl/polymer mud from 1035 m to TD.

The top of the Tertiary was encountered at 604 m. No indications of overpressured shallow gas were seen. The top of the Tomma Formation (Fangst Group) was penetrated at 2436.2 m and consisted of two hydrocarbon bearing sandstone units separated by a ca 2 m thick shaley interval at 2468 m. For the two units as a whole the logs gave an average SW of 19.4% over the 60.6 m reservoir and a net/gross ratio of 0.921. RFT pressure data indicated a common pressure regime across the shale band at
wlbHistoryDateUpdated: 2016-07-06T00:00:00