As you know, the deepwater Gulf of Mexico has been shut down until late November by an Obama administration-ordered moratorium following the April BP (NYSE: BP) explosion and oil spill. Indeed, even some of the shallower areas of the Gulf have been hit by the chaos.

Despite the Brazilian government's pressure to become a bigger part of the nation's oil picture, including its state-owned oil company Petrobras (NYSE: PBR), it's hard to miss the progressively increasing attention the area is gaining worldwide. The latest wrinkle from the biggest South American country is the possibility of China's CNOOC (NYSE: CEO) jointly bidding a rumored minimum $5 billion to $7 billion with China Petrochemical Corp. (aka Sinopec) for something approaching a 30% stake in OGX Petroleo & Gas Participacoes, SA.

OGX is based in Rio de Janeiro, and has found oil discovery success during the past few months in the 29 blocks in which it is active, mostly in the shallow water. In the meantime, given the possibility of a deal, OGX has transferred its Campos Basin assets to a separate company. It appears that any potential deal could include a combination of asset sales, along with an equity component.

At the same time, while China appears to be in the lead for any potential Brazilian sale, those who have been watching the potential sale develop also list ExxonMobil (NYSE: XOM), along with Chevron (NYSE: CVX) and Statoil (NYSE: STO), as potential buyers. China has already become the largest investor in Brazil, and not solely for energy.

The rapidly developing Asian country -- which has become the world's second-largest economy -- also has tapped Brazil's plethora of natural resources for iron ore mines and farmland. But that's hardly the extent of China's resource blitz. Last year Sinopec paid about $8 billion for Addax Petroleum Corp. Earlier this year it came away with a $3 billion, or 40%, stake in Peregrino, a Brazilian offshore field that was then 100% owned by Statoil.

OGX has about 3.69 billion barrels of potential reserves in seven of its Campos Basin blocks, according to certification last year by DeGoylyer & MacNaughton. Discoveries this year almost certainly have added to that total.

All in all, given CNOOC's active movement around the world, I'd urge Fools to keep an eye on the peripatetic Chinese company. At the same time, it's difficult to counsel investors to ignore ExxonMobil for its quality management and its own geographic spread.

Fool contributor David Lee Smith doesn't own shares in any of the companies named above. CNOOC is a Motley Fool Global Gains pick. Chevron, Petroleo Brasileiro, and Statoil ASA are Motley Fool Income Investor choices. The Fool owns shares of ExxonMobil. Try any of our Foolish newsletter services free for 30 days.

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