Oil and gas explorer Ithaca Energy has drilled and fully cased the final production well on the Athena field in the UK North Sea.

The 14/18b-A2Z well encountered a considerable section of oil saturated net reservoir, with good porosities.

The development well intersected 515ft measured depth of net reservoir in the sub horizontal section of the well bore that was drilled to a total measured depth of 15,497ft.

Ithaca said the project remains on schedule for production start up in the fourth quarter of 2011 at about 22,000 barrels of oil per day (gross).

The company drilled the well directionally to the northwest of the field where it encountered the principal reservoir section, the Scapa A reservoir, at 11,967ft measured depth, 8,851ft (true vertical depth subsea), in line with prognosis.

Electric logs acquired across the entire reservoir section of interbedded Scapa age sandstones and shales confirmed a series of reservoir sands with porosities up to 20%.

Two of the thickest, high porosity sandstone units were encountered close to the top of the reservoir section and they are expected to contribute to strong flow rates when the well comes into production.

Ithaca holds a 22.5% stake in the Athena field and is its operator, and other joint venture partners are Dyas UK (47.5%), EWE Aktiengesellschaft (20%) and Zeus Petroleum (10%).