By OGJ editors
HOUSTON, Oct. 30 -- Appraisal drilling of Okwok marginal oil field off southeastern Nigeria has revealed "significant commercial potential" and raised the prospect that the field could go on production as soon as early 2008, said Oriental Energy Resources Ltd., Abuja.
Oriental operates the field on a farmout from ExxonMobil Corp. in OML 67 in 150 ft of water 25 miles off Nigeria just west of Cameroon and Equatorial Guinea waters (OGJ Online, July 3, 2006). Addax Petroleum (Offshore Nigeria) Ltd., technical advisor to Oriental, operates adjacent OML 123, producing 50,000 b/d of oil.
Okwok appraisal drilling indicated "a complex petroleum system with a variety of crude oil gravities and significantly overpressured zones," Oriental said. "The combination of light oil, high pressures, and the excellent quality reservoirs we have encountered thus far encourage us to believe that the Okwok field has significant commercial potential."
The main reservoir objectives are a series of stacked Plio-Pleistocene age sandstones, known locally as the Lower D sands, at 3,000-4,000 ft subsea. Oriental tested light, sweet crude oil from these sands.
The field is divided into three fault blocks based on 3D seismic mapping. Oriental drilled four wells since July 1 that encountered oil of 32°, 37°, and 26° gravity.
The four wells cut as much as 97 ft of net oil pay and flowed at rates as high as 1,222 b/d of oil.
Objective of the 2007 appraisal drilling phase now being designed is to confirm sufficient oil reserves to accelerate development. Okwok could be produced through the OML 123 floating production, storage, and offloading vessel 12 km north.
Addax averaged 83,000 b/d in the first 8 months of 2006 from fields in several blocks in which it holds interests offshore and on land in the Niger Delta.
