Wellesley Petroleum and its partners have confirmed a gas and condensate discovery at the Carmen prospect in the Norwegian North Sea following the completion of appraisal well 35/10-16 S.
The well was drilled approximately 25km north-west of the Troll field and 35km east of the Kvitebjørn field within production licence 1148.
Preliminary estimates place recoverable resources from the Carmen discovery at between 3.4 million standard cubic metres (mscm) and 17mscm of oil equivalent, equating to 21–107 million barrels of oil equivalent (mboe).
The discovery is situated in a licence awarded in 2022 through the APA 2021 licensing round.
The 35/10-16 S well is the third to be drilled in production licence 1148, operated by Wellesley Petroleum. The other partners are DNO, Equinor and Aker BP.
The group is now considering options for tying back the Carmen discovery to existing nearby infrastructure and is also evaluating the potential for further wildcat drilling in the area.
According to geological data, the appraisal targeted delineation of the Carmen discovery confirmed by wells 35/10-10 S and 35/10-10 A, which were drilled in 2023.
Multiple reservoir zones containing hydrocarbons were identified, including in the Ness, Etive and Oseberg formations of the Middle Jurassic and the Cook Formation in the Early Jurassic.
The lower part of the Ness Formation contained a 14.6m column of gas and condensate in reservoir rocks described as ranging from poor to very good quality, with no gas/water contact observed.
In the Etive Formation, a 41.3m column was encountered, also with no gas/water contact.
The Oseberg Formation yielded a 5m hydrocarbon column, with the gas/water contact measured at 3,966m below sea level. The Cook Formation held aquiferous rocks with hydrocarbon shows but no commercial accumulation.
The well was drilled by the Deepsea Yantai rig to a vertical depth of 4,153m below sea level in the Amundsen Formation, with the water depth at the site recorded at 365m.
The well has now been permanently plugged and abandoned. The Deepsea Yantai is set to drill the next appraisal well, 35/7-2, at the Afrodite discovery in production licence 293.
In July 2024, Wellesley Petroleum confirmed the presence of oil and gas at the Gnomoria appraisal well (35/10-12 S) in the North Sea, approximately 100km south-west of Florø, Norway.