Spring Energy reports an oil discovery in the 8/10-4S well on the Butch prospect in PL 405, located about 15 km East of the Ula and Gyda Fields in the Southern North Sea.

The objective of the 8/10-4S well was to prove hydrocarbons in the Jurassic Ula Formation reservoir sands.

The well proved oil in a high quality Ula Formation reservoir about 55 meters thick, and the entire reservoir section was oil bearing. Extensive data acquisition including coring and fluid sampling has been carried out. In order to locate the oil-water-contact a sidetrack well 8/10-4A was drilled downflank and intersected a water bearing Ula Formation. Due to technical issues with the 4A well, a technical sidetrack - 4 T2 was drilled. The main objective for this well was to acquire pressure data in order to establish the oil-water contact.

Preliminary resource estimates indicate a discovery with recoverable reserves of 30-60 million barrels of oil equivalents.

Drilling of a second side track well is planned following the P&A of the current well. The objective of this second side track well (8/10-4B) is to prove additional oil volumes in the same formation in a segment further south on the Butch structure.

The 8/10-4S well was drilled to a total vertical depth of 3066 m below sea level to the Triassic Skagerrak Formation.

The well was operated by Centrica Energi Norge AS on behalf of the PL 405 license group, using the rig Maersk Guardian. Spring Energy holds a 15 % working interest in the license.

Spring Energy has committed to a further 5 exploration wells, in addition to the currently ongoing drilling operations on the Butch oil discovery.

Tags: Spring Energy