Vår Energi ASA discovered oil north of Ringhorne Øst field, 200 km northwest of Stavanger in the operated Balder area of the Central North Sea.
The latest Ringhorne North exploration well in production license (PL 956) is estimated to hold recoverable resources of 13-23 million bbl of oil and will be considered for tie-in to nearby existing infrastructure.
The Ringhorne North exploration well and two additional side-track/appraisal wells (wells 25/8-23 S and 25/8-23 A & B were drilled by the semi-submersible rig Deepsea Yantai, 8 km north of Vår Energi-operated Ringhorne field.
“The discovery supports the plans for continuous development of the Balder area as a long-term production hub in the North Sea. In addition to unlocking new resources and proving the northern extension of Ringhorne field, the Ringhorne North discovery also de-risks more drillable prospects in the area and opens up potential development synergies with other nearby Vår Energi operated discoveries such as King-Prince and Evra-Iving,” the company said in a release Apr. 17.
Geological information
The primary exploration target for well 25/8-23 S was to prove petroleum in reservoir rocks in the Ty formation in the Palaeocene and in the Skagerrak formation in the Triassic. The secondary exploration target was to prove petroleum in reservoir rocks in the Nansen formation in the Lower Jurassic, the Norwegian Offshore DIrectorate detailed in a separate release.
The objective of sidetracks 25/8-23 A and 25/8-23 B was to prove petroleum in reservoir rocks in the Ty formation and Nansen formation, respectively.
Well 25/8-23 S, drilled to a measured depth of 2,454 m subsea and terminated in basement rock, encountered a 5-m oil column in the Ty formation in sandstone with good to very good reservoir quality. The oil-water contact was not proven. The Nansen formation was encountered with a total thickness of 15 m, of which 12 m were sandstone with good to very good reservoir quality with traces of oil. The well encountered the Skagerrak formation with a total thickness of 137 m, of which 20 m were of moderate to poor reservoir quality. The formation was aquiferous.
Well 25/8-23 A was drilled to measured and vertical depths of 2,264 and 2,001 m subsea, respectively. Well 25/8-23 B was drilled to measured and vertical depths of 2,206 and 1,955 m subsea, respectively.
Well 25/8-23 A did not encounter sandstone in the Ty formation.
Well 25/8-23 B encountered an 8-m oil column in the Nansen formation. The reservoir showed a total thickness of 17 m, of which 13 m were of good reservoir quality. The oil-water contact was proven at 1,917.5 m subsea.
The wells were not formation-tested, but extensive data acquisition and sampling was undertaken.
Water depth at the site is 127 m. The wells have been plugged.
Vår Energi is license operator with 50% interest. Partners are Aker BP ASA (20%), Harbour Energy Norge AS (15%), and Sval Energi AS (15%).
