Prospector 5; Source: Borr Drilling

First Glengorm appraisal well in UK North Sea ‘not commercial’

Exploration & Production

The first appraisal well on the CNOOC-operated Glengorm gas field in the UK central North Sea has found “no commercial hydrocarbons”.

Prospector 5; Source: Borr Drilling

Energean, CNOOC’s partner in the field, said in its 2020 full-year results announced on Monday that the Glengorm South appraisal well contained no commercial hydrocarbons.

According to the company, the existing Glengorm North discovery and the Central appraisal well, which is expected to spud shortly, are considered to be independent of the South appraisal well.

The Glengorm discovery is located in License P2215 with a water depth of approximately 86 meters. It was discovered in January 2019 using the Prospector 5 rig.

Glengorm
Glengorm location; Source: Total

The well was drilled to a total depth of 5,056 metres and encountered net gas and condensate pay zones with a total thickness of 37.6 meters. Recoverable resources are estimated at close to 250 million barrels of oil equivalent. At the time, it was the largest gas discovery in the UK since Culzean in 2008.

The gas at Glengorm is subject to very high pressures and temperatures, which makes it more challenging and costlier to develop. But with other such fields in the vicinity, like Elgin/Franklin and Culzean, CNOOC could tie it to one of those fields.

At the time of the discovery, CNOOC – as the operator – held 50 per cent of the stake in Glengorm. Its partners were Total with 25 per cent and Edison Exploration & Production which held the remaining 25 per cent.

In December 2020, Energean took over 25 per cent of the field through the acquisition of Edison Exploration & Production from Edison S.p.A. for an initial consideration of $750 million.

Although Glengorm appraisal was not fortunate, CNOOC had more luck offshore China. Namely, it started production from the Caofeidian 6-4 oilfield located offshore China last month.