Chinese big three, ONGC chase Marathon Angola asset

By Tom Miles

HONG KONG, Aug 11 (Reuters) - U.S. energy firm Marathon Oil Corp is selling a 20 percent stake in an Angolan oil field that could fetch almost $2 billion, attracting bids from China's top three oil firms, India's ONGC and Brazil's Petrobras, sources close to the matter said.

Marathon (MRO.N) is selling 20 percent of its 30 percent holding in Angola's offshore Block 32 as part of an asset review which the company hopes will raise $2-4 billion within a year.

The value of the asset has been boosted by Angola approving development of neighbouring Block 31 last month, paving the way for oil firms to book the reserves of the potentially huge resource.

Marathon has said it expects to get government permission for the development of Block 32 about 12-18 months after Block 31.

The two blocks together hold up to 2-3 billion barrels of oil equivalent that have already been discovered and remain unbooked by the companies involved, Neil McMahon, an analyst at Bernstein Research, wrote in a note to clients last month.

The ultra-deepwater offshore field is of interest to China, which covets deepwater drilling technology for development of its own offshore blocks.

Sources familiar with the bidding process said Chinese refining giant Sinopec had teamed up with China's offshore specialist CNOOC to bid. Unusually, top Chinese oil producer CNPC had also made a separate bid.

One energy banker not directly involved in the process said he expected ONGC (ONGC.BO) to be a very active bidder, since it had bid aggressively for the last Angolan offshore block that was available.

Brazilian deepwater specialist Petrobras (PETR4.SA) was also bidding, while one energy banker said he expected the field to be of interest to U.S. and European majors such as ENI SpA (ENI.MI).

Bidding in the sale process, run by energy consultants Harrison Lovegrove, has now finished and moved to the negotiation stage, which could end within days, with the final price likely to be close to $2 billion, a source familiar with the matter said.

Marathon has already sold off North Sea assets as part of its asset review. Selling 20 percent of its stake in Angola's Block 32 would leave it with 10 percent, bringing it into line with its holding in Block 31.

The remaining interests in Block 32 are held by operator Total (TOTF.PA) (30 percent), Sonangol (20 percent), Exxon Mobil (XOM.N) (15 percent) and Petrogal (5 percent).