Oilfield Reactivation, Rejuvenation, Rehabilitation and Redevelopment: North Sea Case Histories
Rejuvenation of old oilfields is not a new idea. However, only in the last decade and a half has the process become a common one. A survey of the Society of Petroleum Engineers' (SPE's) online library showed a progressive increase in publications containing the keywords ‘redevelopment', ‘rehabilitation', ‘rejuvenation' or ‘reactivation'. There are several reasons why oilfield rehabilitation should become popular.
- Technology has in decades past improved typical recovery factors from 10% in the 1920s to 50%+ today.
- ‘Good' exploration acreage is getting harder to find as many of the world's basins become thoroughly drilled.
- Many countries once closed to western oil companies have opened to investment and typically these countries invite investment in old oilfields rather than exploration.
Although the observations outlined above are global trends, similar patterns are emerging in individual oil provinces. The North Sea is by global standards a young oil province and it does not match all of the criteria cited above nonetheless it is proving attractive to a combination of companies with long histories in the North Sea E&P business, North American independents and indigenous start-ups.
Here we examine what is happening in the North Sea; where the interest lies for companies practicing rejuvenation and what the advantages and the pitfalls are. Case histories both from personal experience and public domain data are presented.