West Heather drilling started - potential boost for DNO's oil reserves

DNO Heather Limited, a wholly owned subsidiary of DNO ASA ("DNO") has on 9 August 2001 commenced drilling of an exploration well in UK Block 2/5 south-west of the Heather Platform to a target in the adjacent Block 2/4. One of the well objectives is to test the potential recoverable oil resources in a structure of Upper Jurassic age that has been identified based on interpretation of 3-D seismic aquired in 1995. This structure is located at the western edge of the North Viking Graben, an area where there is believed to be significant potential for hydrocarbon bearing sandstone reservoirs.

The potential recoverable oil resources in the structure is estimated at about 60 - 220 million barrels, with an estimated probability of success of 10 %. DNO has 100 % interest in Block 2/4 and 2/5.

- "There is a great potential in this Upper Jurassic structure, and successful results from the drilling can therefore lead to a boost in our oil resourcesl", says Helge Eide, Managing Director in DNO ASA.

The oil resources in the Heather Field and adjacent satellites, exclusive of the Upper Jurassic structure are estimated at about 50 million barrels. The Upper Jurassic structure clearly has the potential to make a substantial impact on the area's oil resources and DNO's future production from the Heather Platform. A possible development of an oil discovery will imply drilling of sub-sea production- and injection wells with the oil production to be tied back to the Heather platform through a 7.5 km pipeline.

DNO has engaged the semi-submersible drilling rig SS Petrolia for the drilling in Block 2/4 and 2/5. The drilling of the Upper Jurassic structure has an estimated duration of 50 days.

The location of the Upper Jurassic structure compared to the Heather Field and satellites is shown on the attached sketch.