ONS 2016: Faroese geology under review ahead of 2017 licensing round
Faroese Geological Survey (Jarðfeingi) is revisiting large amounts of data from exploration activity offshore the Faroe Islands.
It plans to brief interested oil companies on the results of the new interpretations during the run-up to next year’s 4th Faroese offshore licensing round.
Only nine offshore wells have been drilled to date in Faroese waters since exploration started in 2000. The last two – on theBrugdan and Súlan/Stelkur prospects – were drilled in 2014. Brugdan had to be re-drilled after the original well encountered technical difficulties in 2012.
Five of the wells encountered hydrocarbon traces while two, includingEni’s Anne Marie well, intersected gas columns of up to 350 m (1,148.29 ft) thickness in the volcanic section.
Although no viable reservoir was found, the finds did confirm the existence of an active hydrocarbon system and suggested the potential for deeper-lying reservoirs.
The main issue that has deterred would-be drillers is the complexgeology, mainly the volcanics that extend right across the Faroese shelf, which hinder imaging of potential underlying reservoirs.
In Brugdan’s case, the overlying volcanics sequence is at least 3 km (1.86 mi) thick, said Jarðfeingi geologist Jana Ólavsdóttir at ONS last week.
There are other petroleum provinces with volcanics, notably in Angola and Brazil. However, the volcanics layers in these regions are not nearly as thick, making it difficult to draw meaningful analogies.
Across the median line in UK waters, there are geological similarities, Ólavsdóttir said, but not all the UK area is covered by volcanic material.
The pre-volcanic sediments in the Faroese area appear to have come from Greenland while the equivalent strata in the UK area are mostly the result of localized erosion.
This discrepancy stems from the fact that when the volcanics were formed and beforehand, the Faroe area was a conjugate part of east Greenland.
Bidders for next year’s round can draw on a fairly extensive 2D and 3D dataset offshore the Faroes. This is of variable quality, but modern imaging and reprocessing techniques are delivering better results.
“We have seismic data – so far not released – that has been improved following re-processing. Now we see the base of the volcanics and the pre-rift, although there are no tie points. But we can’t establish these until more wells are drilled through the volcanic sequence,” Ólavsdóttir said.
Currently at least 12 specialists from Faroese Geological Survey (Jarðfeingi) and other institutions are in the process of revisiting large amounts of data from the Faroese area, she added.
“As we move forward, the picture becomes clearer and we expect to announce the results of the new interpretations at the opening of the 4thFaroese Licensing Round next May.”
The areas that will be offered are to the southeast of the islands. Other previously less-explored areas will be opened up in the future, as the Faroese government is considering staging licensing rounds every two-three years.
Share your news withOffshoreat email@example.com