Whilst Neptune is working on the next phase for the Dugong discovery, Equinor and partners Petoro (30%), Wintershall Dea (24.5%), Idemitsu (9.6%) and Vår (4.9%) are now drilling a prospect that is along the same geological trend.
Only about five kilometres to the northeast of Dugong, also situated in the downfaulted terrace immediately north of the Snorre field, well 34/4-17S is targeting a Triassic-Lower Jurassic reservoir within the Statfjord Fm in PL057. The Middle Jurassic Rannoch Fm, which is the main reservoir in Dugong, is not present in the area of the well.
Very close to 34/4-17S lies an exploration well that was drilled in 1994 by Saga Petroleum. The good thing about these “older” wells, and especially the ones drilled by Saga, is the fact that in some cases a cross-section is included in the documents available through the NPD website. That’s the case here.
The cross-section shown below is from the 34/4-8 completion report and nicely shows the fault block that was targeted by the well. Although some shows were observed in sandstones within the overlying Upper Cretaceous Shetland Group, the Statfjord target reservoir was dry.
It is most likely that the slightly more updip fault block to the east of 34/4-8 is now being targeted by well 34/4-17S. Given the larger offset between the bounding fault on the eastern side of the fault block, it could be that there is more effective fault sealing than in the case of 34/4-8.
Well 34/4-17S is another example of near-infrastructure exploration, targeting modest volumes which may extend the life of Snorre – where more than 500 MMboe of reserves still remain – a little.
HENK KOMBRINK
