Brazilian state-run energy giant Petrobras (PBR) notified the country's National Petroleum Agency late Wednesday that it had found traces of oil in a wildcat well in the offshore Santos Basin.

The first discovery was made in the BM-S-7 offshore block. The 9BRSA741SPS well was spudded by the Pride South Atlantic rig to a total depth of 4,625 meters, ANP drilling data showed. The same well showed indications of oil in early August.

The BM-S-7 block also contains the Piracuca discovery, estimated to hold light oil and natural gas reserves of about 550 million barrels of oil equivalent. The announcement was made in April by Petrobras and Spain's Repsol YPF (REP), which declared the field commercially viable.

Petrobras holds a 63% stake in the block, while Repsol holds 37%.

Oil companies operating in Brazil must inform the ANP of indications of oil, gas or hydrocarbons in any exploratory well within 48 hours. The disclosures are routine, and do not indicate commercial viability.

-By Jeff Fick, Dow Jones Newswires; 55-21-2586-6085; jeff.fick@dowjones.com