In Brazil, state-oil company Petrobras, partnered by UK exploration company BG, has discovered a huge petroleum field that could amount to the world's third largest reservoir.
A senior energy ministry official has declared the newly-found Carioca field could contain 33 billion barrels of oil and gas. Industry analysts estimate this sum may take into account the reserves of nearby oilfields. More evaluation by drilling will go ahead to establish the size. It could take 10 years before Carioca is ready for production.
Other recent Brazilian oilfield discoveries include Tupi, which has an estimated 5-8 billion barrels of recoverable reserves.
The figures are more than 10 times higher than BG's discovery in the North Sea which brought new optimism about the UK's offshore potential and helped revive drilling interest in the area at a time when local crude prices have been hitting new highs.
Brazil could become one of the world's largest crude oil exporters and may join the OPEC oil cartel. Petrobras has spent more than $8 billion (5 billion) signing up new rigs to explore the deep waters off Brazil.
BG has increasingly targeted Brazil as an important area, having bought a 51% stake in the downstream gas distribution business, Comgas. It has an estimated 8,000 km2 of offshore acreage to explore and holds a 25% stake in the Tupi find and a 30% holding in Carioca.