34/10-53 S

General

Well 34/10-53 S and the subsequent geologic sidetrack 34/10-53 A was drilled in the Rimfaksdalen area, a down faulted and rotated fault-block in between Rimfaks and Gullfaks Sør. The general objective for the two wells was to determine the basis for further development in the Gullfaks Sør and Rimfaks area by exploring the Rutil, Opal and Brookitt prospects. The primary target for well 34/10-53 S was to test the Middle Jurassic Brent Group Rutil prospect while the Early Jurassic Statfjord Formation Brookit prospect was secondary target.

Operations and results

Wildcat well 34/10-53 S was spudded with the semi-submersible installation Deepsea Atlantic on 6 December 2010 and drilled to TD at 4526 m (3879 m TVD) in the Early Jurassic Statfjord Formation. A pilot hole was drilled from surface to top Utsira Formation to check for shallow gas. No shallow gas was observed. No significant problem was encountered in the operations. The well was drilled with Sea water and hi-vis sweeps down to 1068 m, with Glydril mud from 1068 m to 2255 m, with Versatec oil-based mud from 2255 m to 3496 m, and with Versatherm oil based mud from 3496 m to TD.

The 34/10-53 S track encountered the Brent Group (Rutil) at 3634 m (3361 m TVD), which was 28 m shallower than prognosed. A gas column of 181 m TVD was proven in good quality sands throughout the Brent Group, with a GDT of 3945 m (3542 m TVD). Three different pressure systems were proven based on pressure data in the Brent Group. The Statfjord Formation (Brookitt) was encountered 12 m shallow to prognosis at 4423 m (3820 m TVD) and was water wet. No oil shows were reported from the well.

No cores were cut. Fluid samples were taken by MDT on drill pip