ID: 457
OBJECTID: 457
wlbNpdidWellbore: 465
wlbName: 34/7-6
wlbHistory:

General

Well 34/7-6 was drilled centrally on the Snorre Field in the Tampen Spur area of the North Sea. The objectives were to test the reservoir quality of the Statfjord Formation and the extent of the low GOR oil encountered in the 34/7-3 and 34/7-4 wells. Further objectives were to test the proposed subdivision and reservoir characteristics of the Triassic Lunde and Lomvi formations.

Operations and results

Appraisal well 34/7-6 was spudded with the semi-submersible installation Treasure Saga on 17 March and drilled to TD at 3685 m in the Triassic Teist Formation. No significant problem was encountered in the drilling phase. After DST 1 parts of the test string stuck, leaving a fish with top at 2533 m in the hole. The fish was pushed down 12 m to give space for further testing. The well was drilled with spud mud down to 965 m, with gypsum/polymer mud from 965 m to 3015 m, and with Drispac/Ligcon mud from 3015 m to TD.

Apart from the sandy Utsira Formation of Late Oligocene - Pliocene age, and sandstone units of Early Oligocene age (1215 - 1280 m) and Middle - Late Eocene age (1370 - 1420 m) within the Hordaland Group, the upper section down to the Jurassic proved mainly claystones. The Jurassic consists of a silty Dunlin Group and a sandy Statfjord Group. The Triassic had sandstones alternating and interbedded with claystones down to TD.

Silty laminae in the Shetland Group had traces of shows from about 2110 m. These were described as gold yellow fluorescence with no cut. From 2155 m and down to 2500 m silt and sandstone show golden yellow fluorescence and slow streaming cloudy yellow fluorescence cut. Occasionally light brown staining and weak odour are observed from 2500 m. H
wlbHistoryDateUpdated: 2016-07-06T00:00:00