6608/10-14 S

General

Well 6608/10-14S was drilled on the Fossekall prospect on the Dønna terrace in the Norwegian Sea. The well is located 8 km north of the Svale field and 15 km northeast of the Norne field. The objective was to prove hydrocarbon bearing sands in the Ile, Tofte and Åre formations (Fangst and Båt Group) of Middle - Early Jurassic age in the Fossekall prospect and to establish fluid contacts.

Operations and results

Wildcat well 6608/10-14S was spudded with the semi-submersible installation Ocean Vanguard on 22 February 2010 and drilled to TD at 2880 m (2771 m TVD). The well was designed as a vertical well down to the 12 1/4" hole section at 1332.5 m and then directionally drilled from the 12 1/4 section to hit the geological target at a ca 30 deg angle, holding this inclination to TD of the well. No significant problem was encountered in the operations. No shallow gas observed. The well was drilled with Seawater and CaCl2/Polymer down to 1332.5 m and with "yellow" Enviromul oil based mud from 1332.5 m to TD.

The well penetrated a 6 m thick Spekk Formation at 2375 m on top of the Melke Formation at 2381 m. There were two main reservoir levels in Fossekall; Melke Formation of Late Jurassic age and in the Ile, Tofte and Åre Formations of Middle to Early Jurassic age. The two reservoir levels are separated by the Not Shale. Gas was observed in Intra- Melke Formation sandstone from 2433 m (2380.1 m TVD) to 2504 m (2441.5 m TVD), while oil was present in sandstones from top Ile Formation at 2549.2 m (2480.9 m) and down through the Tofte and Åre Formations. MDT sampling and fluid scanning found water up to 2714 m (2623.9 m TVD), while the logs and shows on cores indicate moveable oil down to a thin sand at 2704.5 m (261