2/9-4

General

The 2/9-4 Trane well is located on the Piggvar Terrace in the Norwegian Sector of the Danish-Norwegian Basin in

the North Sea. The target prospect was seen as a continuation of the recent Danish sector Hejre discovery structural trend and reservoir/trap system and the sole objective of the well was to explore the hydrocarbon potential of the Jurassic J62 Heno Formation (Gert Member Sandstone) prospect. The 2/9-4 well location was planned to be approximately 10 km from the Danish sector Hejre-2 well location. The Trane well was planned as a near-vertical HPHT well with a prognosed TD at 5512 m or when sufficient rat hole was drilled below the base of the Karl Volcanics to allow testing in the discovery case and full coverage logging in the wet case.

Operations and results

Wildcat well 2/9-4 was spudded with the jack-up installation Mærsk Galant on 20 March 2008 and drilled to TD at 5500 m in volcanic rocks within the Permian Rotliegend Group. An apparent influx into the wellbore was observed while drilling at 5056 m with 16.9ppg MW and required an increase in MW to 17.0 ppg to allow drilling to continue. The ECD immediately prior to this "influx" had been 17.2 ppg and the influx was thought to have been caused by gas expansion near surface after drilling into a gas pocket trapped beneath a thin dolomitic limestone stringer. A flow check at 5116 m due to high drilled gas levels in the mud showed the well was flowing at 14bbl/hr with a MW of 17.4ppg. The well required 17.7 ppg MW to return to a static condition. The Pore Pressure through this section was significantly higher than the pre-drill estimate and appeared to indicate that the Trane structure represented an isolated block with a different structural a