Oron West and North Oron—Combined Development of Two Adjacent Fields, Nigeria

Simantov, Vlasta, Addax Petroleum Services Ltd, Geneva, Switzerland

The North Oron and Oron West fields were discovered in 2002 offshore in the eastern part of the Niger Delta. The fields are located on either side of a major boundary fault. Drilling confirmed that the hydrocarbon accumulations of these two fields are isolated at all strati­graphic levels within the Agbada Formation.

Both discoveries were made based on a 3D seismic survey acquired in 1997/1998. The discovery wells were drilled back to back from the same surface location. They confirmed the presence of an oil column some 100 ft thick in each field in two different reservoir sands. The oil properties are different which is likely caused by different reservoir depths. Successful MDT tests gave the preliminary indication of the commercial value of the discov­eries that was confirmed by the results of subsequent extended well tests.

Static and dynamic reservoir models were built as a base for a field development plan. The main challenge is to develop the fields simultaneously with a flexible drilling programme that allows immediate implementation of eventual modifications to the initial plans for fast­track optimization of drilling and production. Due to their geographical proximity, the fields are being developed from a common well-head/production platform.

In-spite of their proximity and similar geological settings, the accumulations have differ­ent drive mechanisms and require different field development plans. The first development well is scheduled to spud in the first half of 2005.