34/10-52 S

General

Well 34/10-52 S was drilled on the 10AB fault segment in the southern part of the Gullfaks Sør field, located in the northern part of the North Sea. The objective for this appraisal is to prove hydrocarbons and further production potential in the Gullfaks Sør Brent Group and to support decisions on future development in the Gullfaks Sør area.

Operations and results

Appraisal well 34/10-52 S was drilled with the semi-submersible installation Deepsea Atlantic. First spud was 5 August 2009. A 9 7/8" pilot hole was drilled from seabed 165.5 m to 800 m, to check for shallow gas. No shallow gas was observed from the pilot hole. Gas bubbles were observed at wellhead with ROV while pulling out of hole with 26" BHA. The section was displaced to 1.50 g/cc mud and no more gas bubbles were observed. No indications of hydrocarbons were interpreted on MWD/LWD logs from 9 7/8" pilot hole and 26" hole, all sand layers indicated drop in resistivity, hence water filled. Drilled 17 1/2" hole to 1516 m and lost circulation. At the same time lateral wellhead movement was observed. The bore hole was abandoned and a re-spud (34/10-52 ST2) was performed 40 m north on 15 September 2009. This well was drilled to 345 m where the well was observed flowing. The well was plugged back and 20" casing was installed at 301 m. Installed BOP and riser. Decided to suspend the operation and abandon the well due to wellhead movement and technical problems with rig equipment. The well was drilled with sweater and high viscous pills.

Target reservoir was not reached. No cores were cut and no wire line fluid samples were taken.

The well was permanently abandoned on 10 November 2009 as