UPDATE 1-Brazil OGX says finds signs of more oil in Campos

* Oil discovery is OGX's second in the same well

* OGX shares jump on new signs of oil (Adds details, background)

SAO PAULO Dec 28 (Reuters) - Brazilian oil and gas start-up company OGX Petroleo e Gas Participacoes (OGXP3.SA) said Monday it had found signs of more hydrocarbons in well 1-OGX-3-RJS, off Rio de Janeiro's coast in the southern part of the Campos basin.

OGX said in a securities filing it identified a column of more than 180 meters (590-foot) of hydrocarbons.

This was OGX's second strike in the same well, which is located in the BM-C-41 block, at a water depth of around 130 meters, about 83 kilometers (51 miles) off the coast of Rio. The previous one was announced on Dec. 18.

The company, which is part of the EBX energy and infrastructure conglomerate owned by Brazilian billionaire Eike Batista, is the sole owner of the exploration and production concession for that block.

OGX has made a string of hydrocarbons finds in recent months, helping its shares more than triple since the beginning of 2009.

Brazil hopes to become a key world oil producer after the discovery in 2007 of huge crude reserves deep below the ocean floor in an area known as the subsalt province which could contain as much as 50 billion barrels.

The company's shares were up 3.4 percent on the Sao Paulo stock exchange in early trade while the Bovespa index .BVSP rose 0.83 percent. (Reporting by Inae Riveras; Editing by John Picinich)