6608/10-11 S

General

Well 6608/10-11 S was drilled on the Norne field, located on the border betveene Dønnn Terasss and the Nordland Ridge in the south-western of block 6608/10.The primary objective for the exploration well 6608/10-11 S was to establish the existence of hydrocarbons in the Middle and Early Jurassic reservoir sandstones of the Fangst and Båt Group in the Trost prospect. The Trost prospect is located on a down-faulted fault block west of the Norne field. The stratigraphy is similar to the Norne reservoirs, and Not Formation sandstone is the main reservoir.

Operations and results

Well 6608/10-11 S was spudded with the semi-submersible installation Transocean Arctic on 12 July 2006 and drilled to TD at 3725 m (3243 m TVD) in the Tilje Formation. The well 6608/10-11 S was side tracked from Norne Well 6608/10-K-3 H, hence it was designed as a deviated well with kick off point from 6608/10-K-3 H below 13 3/8" casing shoe at 1366.1 m (1328.2 m TVD). The well was drilled with Carbo-Sea oil based mud from kick-off to TD.

The observed stratigraphy from the kick off point and down to the Fangst Group was generally in accordance with the prognosis. The Melke Formation was approximately 33 m thicker than prognosed, and the biggest discrepancies were therefore found from top Not Formation to TD of the well, where the formation tops came in from 36 to 74 m TVD deeper than prognosed.

Gas was proven in the Not Formation sandstone. This was indicated by both gamma ray and resistivity logs, and was confirmed by neutron and porosity logs, together with MDT pressure points. White to very pale yellow direct and slow cut fluorescence was observed in the reservoir section, but was probably largely due to oil based mud fluorescence and its invasion of the cuttings. Similar fluorescence was seen in the lower water zone of the reservoir.

No cores were cut. MDT gas samples were taken at 3511.2 m (3055.5 m TVD).

The well