Afren PLC and Amni International Petroleum Development Co. Ltd. have started production from an extension of Okoro oil field offshore southeastern Nigeria at a stabilized rate of 5,000 b/d of 38º gravity oil (OGJ Online, Mar. 7, 2012).
They drilled the Okoro-14 well development well from the main field wellhead platform on Okoro field to establish early production from a horst block structure deeper than the main Okoro reservoir about 2 km to the east. Production from the extension well flows through a floating production, storage, and offloading vessel on the field.
Afren said the new well is the Okoro area’s most productive. It boosts the area’s total production to 21,500 b/d.
Before drilling the Okoro-14 well, Afren and Amni sidetracked the Okoro-5 production well in the main field seeking oil in a previously unswept part of the reservoir. The sidetrack went to 9,800 ft TMD and encountered pay in the target reservoir. The companies brought a 2,500-ft lateral drainage section in the zone onstream at a stabilized rate of 2,000 b/d of oil.
The Transocean Adriatic IX jack up, which drilled the extension well, has been moved back to Ebok oil field for drilling to include a development well for early production from the Ebok North Fault Block discovery. There, Afren and partner Oriental Energy Resources in May logged 370 ft true vertical thickness of net oil pay in the same Tertiary reservoir sands as the main field on a separate fault block at 4,320 ft TVD.