Preliminary data indicate that this is one of the best prospects in Albiano that our team has found so far in Brazil, said Paulo Mendonca, OGX's director general.
The hydrocarbons were discovered in the well 1-OGX-2A-RJS of block BM-C-41 about 77 km (48 miles) from the Rio de Janeiro coast. The well will continue being explored to a depth of 3,425 meters, the company said in a statement.
No details were given about the potential size of the find or on the kind of hydrocarbons, although the company said it was of high quality.
The block neighbors another controlled by OGX, BM-C-43 whose reserves the company estimated last month at between 500 million and 1.5 billion barrels. A separate discovery of 400 million to 500 million barrels of oil at a different well in the BM-C-41 block was announced two weeks ago.
OGX Petroleo e Gas Participacoes is part of the EBX energy and infrastructure conglomerate owned by Brazilian billionaire Eike Batista. OGX went public in June last year in what was, at that time, the biggest initial public offering in Brazil.
The company has made a string of oil discoveries in the last two months and its shares have roughly tripled in value since the beginning of 2009.
Brazil is set to climb the ranks of the world's oil producers after the discovery in 2007 of huge reserves of crude under a layer of salt rock deep below the sea floor which could contain as much as 50 billion barrels.
Extracting the subsalt oil from depths of up to nearly 8 km (5 miles) in places, will require billions of dollars in investments and pose significant technical difficulties.
(Reporting by Todd Benson; Writing by Peter Murphy; Editing by Lisa Shumaker)