* Anadarko, Repsol and Tullow make another find
* 450 million barrels possible - Citigroup
* Boosts hopes of further finds in the region
* Tullow, Repsol shares rise
(Adds share rise, background and analyst quote)
By Tom Bergin and Martin Roberts
LONDON/MADRID, Nov 15 (Reuters) - A consortium led by U.S. explorer Anadarko Petroleum Corp (APC.N) has made a second oil find offshore Sierra Leone, supporting predictions of a series of big fields along the coast of West Africa
Anadarko said on Monday its Mercury-1 oil exploration well encountered about 135 net feet of oil pay, which analysts at Citigroup said largely confirmed pre-drill estimates of around 450 million barrels of reserves.
Shares in Spanish oil firm Repsol (REP.MC), which owns a 25 percent share in the consortium, rose 0.51 percent on the news, while shares in London-based explorer Tullow Oil (TLW.L), which has a 10-percent stake, rose 0.9 percent.
The STOXX Europe 600 Oil and Gas index .SXEP was flat at 1006 GMT.
“This is another exciting discovery and goes a long way to prove that the company (Tullow) is sitting in a major new hydrocarbon basin that extends from the Jubilee field in Ghana up the coast of West Africa,” said Peter Hitchens at Panmure Gordon.
The news was welcomed in Sierra Leone, which emerged in 2002 from a decade of civil war that killed 50,000 people, which was fueled by the country’s rich diamond deposits.
“The next stage is to make an appraisal and see how soon we can go to production and become an active player in the oil and gas industry,” said Tomah Nhabay, Acting Director General, Petroleum Resources Unit of the Sierra Leone government.
In September last year, Anadarko said its Venus B well had confirmed the existence of an active petroleum system offshore Sierra Leone.
This raised the Houston-based company’s hopes for more than 30 other prospects in that part of West Africa.
Anadarko said it also planned to continue working with the government of Sierra Leone to accelerate exploration and appraisal activity in the area in 2011.
Anadarko holds an interest in more than 4.6 million acres on five deepwater blocks offshore Sierra Leone and Liberia. (Additional reporting by Simon Akam in Sierra Leone and Sakthi Prasad in Bangalore)
Editing by Erica Billingham and Jane Merriman