Brazil's state-owned Petrobras confirmed the discovery of a significant amount of light oil in the Santos Basin.
The confirmation was made after the company conducted tests in a vertical well and detected a flow of 4,900 barrels of oil and 150,000 cubic meters of natural gas per day. The highly productive reservoir was found under a 2,000-meter thick layer of salt, also known as pre-salt.
Petrobras said it would make further investigations to determine the total oil and gas reserve of the well.
According to experts, a reservoir that lies underneath a layer of pre-salt is commercially viable if its total capacity exceeds 700 million barrels.
Although drilling a well of this kind required a big investment, it was worthwhile because the rewards would be high, said Marcio Rocha, a geologist from the Brazilian Association of Petroleum Geologists.
There may be other wells below the pre-salt layers in the deep waters of the Campos Basin in the Rio de Janeiro state, said Rocha.
The new well was discovered during exploration being carried out by a consortium comprising Petrobras, the UKs' BG Group and Portugals' Petrogal.