Angola requests bids for 10 onshore oil blocks

(Adds details on bidders and reserves)

LUANDA, July 20 (Reuters) - Angola's state oil firm Sonangol on Monday requested prequalified bidders to submit bids for ten onshore oil blocks as Africa's second largest crude exporter aims to open up new exploration opportunities.

U.S. oil major Chevron, Italy's ENI (NYSE: E - news) , commodities trader Glencore (Xetra: A1JAGV - news) and Portugal's GALP were among the prequalified companies who could operate the blocks, Sonangol said in a press release.

Bid proposals must be submitted by September 18.

Sonangol said last year that the 10 blocks may hold, on average, reserves of 700,000 barrels of oil each. The government puts Angola's total reserves at just under 13 billion barrels.

Operators will need to work with Angolan companies as the government seeks to increase local ownership of its resources.

Seven of the new blocks are in the Kwanza basin and three in the Congo Basin.

Angola currently produces around 1.7 million barrels per day of crude oil from large offshore fields developed by oil majors, including Chevron, Total (Swiss: FP.SW - news) , Exxon and BP. (Writing by Joe Brock; Editing by James Macharia)