CALGARY -- Ithaca Energy’s appraisal well on the Stella discovery in the UK central North Sea has proved “significant” additional hydrocarbon volumes, according to the company’s statement.
The well was managed by ADTI, using the harsh-environment Transocean jackup GSF Galaxy II. A drill stem test has also been completed, the results of which should allow development planning to start.
Well 30/6a-8 was drilled to appraise a large down-flank extension of the field. The total measured height of the hydrocarbon column is now over 820 ft (250 m), suggesting reserves greater than previous estimates.
Drilling also confirmed hydrocarbons over 500 ft (152 m) lower than in any of Stella’s previous wells, drilled on the crest of the structure, indicating that connected hydrocarbons are present down to the geological spill.
On test the well flowed over 5,000 b/d of liquids, comprising 2,850 b/d of light oil and 2,150 b/d of water. It intersected a 22.5-ft (6.8-m) section of Palaeocene Andrew sandstone reservoir close to the field’s mapped closure.
Ithaca now plans to drill a geological sidetrack to test the reservoir up-flank between this and the crestal wells. The aims are to further study reservoir quality and to provide compositional data on hydrocarbons at intermediate depths.
Once this evaluation has been completed, Ithaca plans a full-scale development of Stella and satellite fields in the area, including Harrier and Hurricane. Partners in blocks 30/6a are Dyas UK and Challenger Minerals (North Sea)