BRASILIA, Feb 10 (Reuters) - Petroleo Brasileiro SA and its consortium partners have concluded drilling and testing of the first well in the Libra prospect, the largest offshore oil discovery in Brazil's history, the state-run company said on Tuesday in a securities filing.
Petrobras said the tests confirmed the existence of a 280-meter column of oil with an API gravity of 27 degrees in the well known as 3-RJS-731.
"The two tests, carried out in different areas, confirmed the excellent productivity and quality of the oil in those reservoirs," the filing said.,
Libra was the first Brazilian sub-salt area to be auctioned. The 35-year concession was bought in 2013 by a consortium led by Petrobras, with a 40 percent stake. Other members include France's Total SA and Anglo-Dutch Royal Dutch Shell Plc with 20 percent each, as well as China's National Petroleum Corp and CNOOC, with 10 percent each. (Reporting by Anthony Boadle; Editing by Christian Plumb)