UPDATE 1-Afren upgrades Nigeria Ebok estimates after tests

LONDON, Dec 10 (Reuters) - London-listed oil and gas company Afren Plc said it is upgrading its oil volume estimates for the offshore Nigerian Ebok complex after better-than-expected well appraisal results.

Afren said it has upgraded the total Ebok resource potential to 167 million barrels (mmbbls) of oil after positive drilling results at the Ebok-5 well. Meanwhile estimated volumes at the Ebok Fault West have been upgraded by 72 percent to 158 mmbbls oil.

'The better than expected Ebok-5 well results further upgrade the reserve estimates for the project and provide a greater understanding of the broader Ebok - Okwok complex,' chief executive Osman Shahenshah said.

The Africa-focused company, which last month raised 104.9 million pounds from a share placing, said it would raise a further $25 million at the time from the exercise of warrants to boost development at its Ebok-Okwok complex.

Shares in Afren were 4.71 percent higher at 0807 GMT.

(Reporting by Lorraine Turner; Editing by Myles Neligan) Keywords: AFREN/ ([e-mail]; [phone]; Reuters Messaging: [e-mail]) COPYRIGHT Copyright Thomson Reuters 2009. All rights reserved. The copying, republication or redistribution of Reuters News Content, including by framing or similar means, is expressly prohibited without the prior written consent of Thomson Reuters.