ID: 727
OBJECTID: 727
wlbNpdidWellbore: 1673
wlbName: 30/9-11
wlbHistory:

General

Well 30/9-11was drilled on the eastern segment of the J-structure on the Oseberg Sør field in the North Sea. Neighbouring wells 30/9-9 on the J-West and 30/9-5 S on the J-Central proved oil and gas, respectively. The primary objective of well 30/9-11 was to prove reservoir sands and oil within the Brent Group of the J-East segment and define oil/water contacts for the Tarbert/Ness and Oseberg-Rannoch-Etive reservoirs. The well was planned to be drilled 50 m into the Dunlin Formation to a total depth of approximately 2540 m.

Operations and results

Wildcat well 30/9-11 was spudded with the semi-submersible installation Vildkat on 27 October 1990 and drilled to TD at 2570 m in the Early Jurassic Drake Formation. No significant problem was encountered in the operations. The well was drilled with spud mud down to 922 m and with KCl/polymer mud from 922 m to TD.

Top Viking Group, Heather Formation was encountered at 2291 m. Top Brent Group, Tarbert Formation was encountered at 2384 m. The Brent Group was entirely water bearing. Poor, patchy shows on thin sandstone lamina in the Heather Formation were the only indications of hydrocarbons in the well.

Four cores were cut with good recovery. Core 1 was cut from 2382 m to 2403 m in the Tarbert and Ness formations, cores 2 and 3 were cut from 2450 to 2464.5 m in the Ness Formation, and core 4 was cut from 2484 m to 2511 m in the Ness and Rannoch formations. RFT water samples were taken at 2493 m in the Ness Formation.

The well was plugged back for sidetracking on 19 November 1990. It is classified as a dry well.

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