6406/12-3 B

General

The 6406/12-3 S, 6406/12-3 A, and 6406/12-3 B wellbores were drilled in concert on the Pil and Bue prospects in the southern end of the Halten Terrace in the Norwegian Sea. The S and A wells were planned to target the Pil and the Bue prospects, respectively. The first well, 6406/12-3 S tested 1017 Sm3 oil/day with a GOR of 160 Sm3/Sm3 in Intra Melke Formation sandstones. This result led to the decision within the partnership to drill an appraisal of the Pil discovery. The well was designated 6406/12-3 B and was designed to test the Intra Melke Sandstone reservoir encountered along strike from 6406/12-3 S.

Operations and results

Appraisal well 6406/12-3 B was kicked off at 2355 m in well 6406/12-3 S on 2 May 2014. It was drilled with the semi-submersible installation Transocean Arctic to 4315 m in Late Jurassic sediments belonging to the Melke Formation. No significant problem was encountered in the operations. The well was drilled with XP-07 oil based mud from kick-off to TD.

At the top of the Jurassic section, the well encountered a different stratigraphy from the 6406/12-3 S well. Immediately below BCU, a 35 m MD Spekk/Rogn/Spekk succession was penetrated. Hydrocarbons were present within these rocks but not moveable. Below the Spekk Formation, at 3761 m (3440 m TVD), the well encountered over 500 m of Intra Melke Formation sandstones. These sands are interpreted to contain similar facies as those encountered in the 6406/12-3 S discovery immediately below the BCU. The Intra Melke sands contained an 82 m oil column in very good to excellent quality reservoir sandstone with an oil-water contact at 3844 m (3522 m TVD), 18 m deeper than in the 6406/12-3 S well. Pressure data confirmed the same oil gradient as in 6406/12-3 S. The