By Toyin Akinosho
Nigerian deepwater oilfield activity is back in exploratory phase, in the main.
With eight billion barrels of proven reserves, a daily output of 520,000barrels per day of crude oil and a long queue of oil field development projects waiting for approval, the Nigerian deepwater province is far from reaching the fullness of the potential that operators thought it had when the first set of 3D seismic data were acquired 1994.
Some companies hit the mother lode thick and fast (ExxonMobil and Shell are producing Erha and Bonga respectively at around 180,000 BOPD respectively, down from an excess of 200,000 BOPD each and both are working on field extensions). Others (like Conoco Phillips, Statoil),quietly folded their arms when the expected elephants didn’t show up on their telescopes, and yet a company like Agip ignored the rules of deepwater field size versus threshold financial profitability and put the 100 million barrel Abo field, located in 500 metres of water, in production, ramping quickly up to 30,000BOPD. (The production had fallen to 19,000BOPD by early 2008 and was to have been boosted by two new wells drilled later in that year). Devon Energy walked out and Petrobras has gone very quiet. Other operators are caught in the less emotional corridor between the spectacular and the disappointing. Chevron brought Agbami on stream at 65,000BOPD in July 2008 and it has ramped up to 135,000BOPD by December 2008. It’s not just the slowest of the big three producing fields in deepwater Nigeria, the production is far below the expected 180,000BOPD anticipated in the first six months of production for the 800MMBO field, TOTAL’s Akpo is on course for first oil before the end of 2009 and the company’s Usan-Ukot and Egina fields are expected on stream between 2011 and 2012. The last really big deepwater fish on queue for first oil in Nigeria is Bonga SW/Aparo, expected on stream about 2013.
With mixed results all over, oilfield activity in this segment of the Niger Delta basin has come full circle and back to where it all started; the exploratory phase. The mood is: “let’s go and check out what else is there”.
Newcomers and grizzly old hands are completing new seismic acquisition and drilling both rank wildcats and first appraisals, largely in areas that have proven to be prospective.
BG, the British gas company, commenced its drilling programme in the Oil Prospecting Lease OPL 286-DO, which was carved out from what used to be Chevron operated OPL 218. The company plans two wells on this lease before moving to OPL 284, which, DPR officials think “is far more prospective”. Its Ogide 1, located in the general, high pressured Boi -1 area(See story on page 13), is being drilled with the semi submersible rig Sedco 702.
After a sustained period of production and development work, Agip is drilling an appraisal well outside the Abo field licence area. The semi submersible rig MG Hulme Jr has reached a depth of 4,000metres subsea in Oberan 2, the first appraisal of the 2003 discovery in what was then OPL 211(now Oil Mining Lease OML 134). The logging programme is fairly comprehensive, including coring and-if there is oil as expected- testing the well. Agip is hoping that the well confirms or even increases, the 200MMBBO it hopes the Oberan structure holds. Swiss operator Addax, who has largely operated on the shelf, commenced its first major activity in deepwater in December 2008 and is currently completing a 1,000sq km of 3D survey in the Oil Prospecting Lease (OPL 291), lying between 500 and 2,500metres of water. The block was carved out of Chevron’s OML-127 (after production permit was granted) where the giant Agbami is seated. The acquisition will cover the northern part of the block extending into north OML- 127. If this G&G exercise in this block comes out successful, then Agbami might have a good tie-back customer in
Petrobras is on queue to acquire 3D seismic with the PGS vessel that is doing the acquisition for Addax.
America’s largest major in Nigeria does not have exploratory wells on the drilling queue in 2009. ExxonMobil will acquire fourth dimensional 4D seismic data on the Erha field, but it doesn’t plan any drilling, exploratory or development, on any of its operated deepwater acreages in 2009.
Chevron may drill one well in OPL 247, now that it has evaluated the carpet 3D it acquired on the lease The company plans exploration drilling elsewhere in its operated deepwater acreages, but no candidate has been firmed up due to rig scheduling and ranking issues.
There are, for example, three candidates, “but the reserves figures are not giving the operator any comfort”, according to a source at the state owned NNPC, which is the concessionaire for all operated leases in deepwater Nigeria. Chevron is still drilling in Agbami for development and production purposes. Shell and TOTAL, on the other hand, have better defined, active drilling schedule, outside of ongoing development activity. Shell plans to drill four exploratory and appraisal wells, apart from the development work on extending Bonga production farther north. The company completed a 4D seismic acquisition on the Bonga structure in early 2008, but the 2009 exploration and appraisal campaign excludes the general Bonga area. Discussions are ongoing to resolve the dispute around OPL 245, where Shell discovered Etan and Zabazaba, its most recent finds and its not clear if any of the four wells is planned for this lease but some of the appraisal work will certainly be in OML 135, where Shell has the undeveloped discoveries Ngolo, Bolia and the Nnwa-Doro gas field.
TOTAL plans to drill a well in the Continental Oil and Gas held OPL 257, which adjoins SAPETRO’s OML 130. TOTAL is the technical operator of both OPL 257 and OML 130 and -if it works-the proposed well in OPL 257 is meant to be part of the overall development of the Egina field, which is expected to come on stream in 2012.
What’s clear in the overall Niger Delta deepwater 2009 drilling activity, no company is venturing into the outer toe thrust belt. The great story of Nigerian deepwater, in the last five years, is the spate of disappointing wells that were drilled by Agip (Dou 1 and Emein 1, OPL 244), Chevron (Iroko 1, OPL 250), Phillips (Onigun 1, OPL 318), Petrobras (Erimi 1, OPL 324) and Ocean Energy 9Pina 1 and Tari 1, OPL 256). What’s happening may be a lot of exploratory work, but it’s taking place in areas already deemed safe bets.