34/10-54 A

General

Well 34/10-54 A is a geological sidetrack to well 34/10-54 S. The wells were drilled to test the Valemon Nord prospect on the Tjalve Terrace in the North Sea. The prospect is situated north of the Valemon Field, between the Gullfaks South, and the Kvitebjørn fields. The primary objective of well 34/10-54 A was to prove commercial hydrocarbon volumes in the Early Jurassic Statfjord Group.

Operations and results

Wildcat well 34/10-54 A was kicked off from 2813 m in the primary well on 11 February 2014. It was drilled with the semi-submersible installation Transocean Leader to TD at 4656 m (4270 m TVD) in the Early Jurassic Raude Formation. A well influx occurred during coring at 4515 m. The flow was circulated out with the driller's method. Further drilling to TD was hampered by hole problems and sticking of drill string. The well was drilled with XP-07 oil based mud from kick-off to TD.

The Brent Group, although not prognosed, came in at 4076 m (3838 m TVD) underlying only 7.5 m Heather Formation. The Brent Group was gas bearing. The primary target Statfjord Group at 4466 m (4129 m). The well proved a gas/condensate column throughout the Brent Group with an additional gas/condensate column in the Statfjord Group. Gas/condensate was also found in the Cook Formation. Pressure sampling in both wells identified different pressure systems through the sand intervals and show most likely initial reservoir pressures. Pressures were lower than expected, below HP definition. No hydrocarbon/water contacts could be found in the Brent or Cook, and challenging well conditions caused an early TD in the Raude Formation, which is most likely hydrocarbon filled at TD.

A total of 67.2 meters of c