ID: 449
OBJECTID: 449
wlbNpdidWellbore: 457
wlbName: 30/2-2
wlbHistory:

General

Well 30/2-2 was drilled on the Mokkukalven Fault Complex north of the Oseberg Field in the North Sea. The objective was to test possible hydrocarbon accumulations in the Huldra Field, on a structural high that is separated from Huldra discovery well 30/2-1 with significant faults. Well 30/2-1 encountered a 119 m gas column in the Brent Group with a down-to contact at 3793 m. The actual gas/water or oil/water contact could not be established. The main target for 30/2-2 was the Brent Group, believed to be some 70 m deeper than the gas column in 30/2-1.

Operations and results

Appraisal well 30/2-2 was spudded with the semi-submersible installation Dyvi Delta on 19 December 1984 and drilled to TD at 4172 m in the Early Jurassic Drake Formation. When doing the reservoir logging, a radioactive part of the logging tool was left in the hole. This accident caused a sidetrack from 3894 m KB to TD. The sidetrack ran parallel to the original hole at a distance of approximately 20 m. The intention was to drill 50 m into the Statfjord Formation, but the well was finished in the Drake Formation due to hole conditions. The well was drilled with spud mud down to 214 m, with gel/seawater from 214 m to 1023 m, with gypsum/CMC mud from 1023 m to 3802 m, and with gel/lignosulphonate from 3802 m to TD.

Gas bearing Brent sandstone was encountered at 3935 m, with the gas-water contact somewhere in the interval 3975 - 4080 m. No distinct contact was possible to recognize from logs or shows, but later geochemical analyses of the corers indicated a contact at ca 3984 m. Fluorescence indicating shows was first recorded on claystone/limestone cuttings in the interval 2204 m to 2267
wlbHistoryDateUpdated: 2016-07-06T00:00:00