Exploration models with Jurassic reservoir rocks still dominate the Norwegian continental shelf. More than half of the prospects that have been drilled so far this year have middle or upper Jurassic sandstones as their target. This is evidenced by the statistics that Exploration Director Torgeir Stordal of the Norwegian Petroleum Directorate (NPD) presented at NCS Exploration Strategy conference in Stavanger on November 20 and 21.
Stordal said that so far this year, more than 54 wells have been drilled which have yielded 15 discoveries.
The absolute largest discovery of the year is 25/2-21 (Liatårnet), where operator Aker BP has calculated that between 80 and 200 million barrels of recoverable oil have been detected (GEO 05/2019: “New exploration model in the North Sea”). The first appraisal well is now being planned and after that we can expect a more accurate resource estimate.
How much this year’s findings give in total is still uncertain. At best, we are talking about 5-600 million barrels of oil equivalent (o.e.). In comparison, the total Norwegian oil and gas production is approx. 1,500 million barrels o.e. per year. The total Norwegian consumption of oil is approx. 85 million barrels per year. The oil companies thus find far less on the Norwegian shelf than what they produce, but fortunately also far more than the Norwegians consume.
Stordal also provided statistics on how good the oil companies are at increasing volumes ahead of an exploration well. Some prospects have come out better than expected, while others are obviously worse than predicted. His main conclusion, however, was that the companies have done well with their forecasts for wells drilled in 2019. This also applied to the Liatårnet, where the volumes were in accordance with the forecast, but where the geological model was only partially correct (much more oil in the Brent group than expected).
In his talk, Stordal also addressed the problem of time-critical resources. Basically, these are resources that come under “high value barrels”. They are close to infrastructure and provide good finances. Equinor has shown this in connection with the discovery 35 / 11-23 (Echino South), located three km south of the Fram field. The company believes that recoverable resources only amount to 38-100 million barrels o.e., while unofficial sources say this can be as good a return as 500 million barrels in the Barents Sea.
The problem with postponed exploration is that “high value barrels” can be lost. The explanation is that new discoveries may be too small to defend an independent development, but large enough to be linked to existing infrastructure while it still exists. In this connection, Stordal highlighted the exploration activity on the British side of the North Sea; the discovery of Glengorm in the Central Graben proves that it is still possible to make significant discoveries in the North Sea, although several more exploration wells are being drilled at the UKCS than NCS.
In conclusion, Stordal asked a rhetorical question related to old licenses which the NPD believes is “underexplored”. He received a kind of response from Denis Palermo, VP Exploration in Vår Energi, who stated that ExxonMobil had failed to search within the Balder license for decades, and this despite the fact that Vår Energi has defined 17 prospects.
We therefore conclude that there must be good hope of finding even more “high value barrels” on the Norwegian continental shelf.
