* Shell (30 pct), Total (10 pct), Eni (5 pct) selling stakes
* Bids due from shortlisted suitors on Feb. 18
* Blocks produced avg 90,000 bpd of oil in 2012 - document
* Glencore, Mercuria in consortiums shortlisted - sources
By Joe Brock
ABUJA, Feb 12 (Reuters) - Commodity trading houses Glencoreand Mercuria are among the shortlisted consortiums expected tomake final bids on Nigerian energy assets worth around $3billion that three oil majors are selling, sources close to theprocess say.
Trading houses have been marketing Nigeria's crude oil andimporting fuel there for decades. New upstream acquisitionswould help cement their relationship with Africa's biggest oilproducer, a key supplier to Europe and India.
Shell is selling its 30 percent stake in four oilblocks, with France's Total and Italy's Eni also set to profit from their 10 percent and 5 percent shares.The Nigerian National Petroleum Corporation (NNPC) owns theremaining 55 percent.
Shell is also selling the 97-km (60-mile) Nembe Creek oilpipeline, which has been regularly attacked by oil thieves.
Final bids for the stakes in the blocks are due on Feb. 18,the sources said.
Total, Eni and Shell declined to comment. Bidders are boundby a confidentiality agreement and all firms as well as otherparties mentioned in this story either declined to comment ordid not respond.
Shell has already made $1.8 billion from asset sales inNigeria since 2010 as several oil majors choose to cash in ononshore fields in the Niger Delta, where divestment isincreasingly popular due to oil theft and a government drive toincrease local ownership.
Oil majors are still keen to keep the largest and mostprofitable Niger Delta fields and infrastructure, and want toexpand in Nigeria's deep offshore areas.
There is high demand for assets in the Niger Delta, whichholds a large portion of Nigeria's 37 billion barrels of oilreserves. The oil is high-quality, relatively easy to drill, andsome Nigerian companies have said they can better handle thesecurity challenges faced by oil majors.
Shell has kept the specifics of the assets it is sellingsecret, but information from a confidential company document andfrom sources involved in the process reveals new details.
The consensus of five sources is that the combined 45percent stake in blocks OML 18, 24, 25 and 29 is worth around $3billion but could fetch even more due to inflated values put onassets in a country with an increasingly wealthy elite.
The blocks' combined output averaged 90,000 barrels of oiland 60 million standard cubic feet of gas per day (scf/d) in2012 and they hold reserves of 4.6 billion barrels of oilequivalent, the Shell report seen by Reuters said.
A 30-year lease on these blocks was renewed in 1993, thedocument said. Shell has held a stake in them for decades longerand it is unclear how much the firm originally paid.
OML 29 is the most coveted asset, producing a peak of 62,000barrels per day (bpd) of oil and 40 scf/d of gas and holdsreserves of 2.2 billion barrels of oil equivalent (boe), thereport said.
The 45 percent stake in this block could earn $1.5 billionto $2 billion, the sources said.
OML 24 holds 803 million boe, OML 18 has reserves of 1.5billion boe, although most of this is gas, while the smallestasset, OML 25, holds 157 million boe, the Shell report said.
The Nigerian sales are part of a wider plan by Shell todispose of $15 billion of assets this year and next tostreamline operations after a profit warning.
HIGH DEMAND
Due to Nigerian government policy to increase local oil andgas ownership, any foreign companies wanting to buy divestedassets needs to partner in consortiums with Nigerian firms.
Glencore is preparing to bid in a consortium, which ifsuccessful would be its first inroad into Nigeria's upstreamsector. Seplat, a Nigerian firm in which Swiss oil traderMercuria and French explorer Maurel and Prom holdminor stakes, is among the shortlisted bidders, sources said.
Africa's richest man, Aliko Dangote, is part of ashortlisted consortium, two of the sources said. Dangote isseeking to expand his vast business empire into the energysector. He has pledged to build a $9 billion refinery in Nigeriaand needs oil reserves to run it.
Nigerian firm Greenacres, whose chairman is former ShellNigeria boss Basil Omiyi, has partnered with Canadian companyOracle Energy to bid on the blocks, the sources said.
Firms that have done deals on Shell blocks previously arealso in the mix, they said. These include London-listed HeritageOil, which will bid with the Bayelsa Oil Company intheir new joint venture, Petrobay. Eland Oil and Gas isshortlisted too, the sources said.
Nigeria's First E&P, Sahara Energy, South Atlantic Petroleumand conglomerate Transnational Corp are separately bidding as isa consortium involving rapidly growing local oil trading firmsTaleveras and Aiteo, the sources said.
Choosing the right buyer, rather than the highest bidder,can be crucial to securing sales, in a country where politicalinfluence can decide deals and legal disputes can scupper them.
U.S. energy company Chevron is embroiled in a legalbattle over its own sale of three Niger Delta blocks.ConocoPhillips has been trying to close a $1.79 billiondeal for over a year as Nigerian buyer Oando struggled to raise the cash, although Oando said this month ithad secured financing.
The Niger Delta has had a host of security challenges sinceoil production began there more than 50 years ago. In 2006,militants claiming to be fighting for a fairer share of oilrevenues cut out a third of Nigeria's production by sabotagingpipelines. Now, widespread oil theft can shut in as much as400,000 bpd of the country's 2.5 million bpd capacity.
Whichever company buys Shell's blocks will have trickynegotiations with NNPC over who operates the fields. The statefirm wants its producing arm NPDC to operate more reserves butoil companies would prefer to have control over the work.