As oil prices have risen unprofitable reserves like those of the Orinoco are now extractable. According to US Department of Energy claims reported by the BBC "Venezuela's deposits alone could extend the oil age for another 100 years."
Extract from the BBC report follows, full report is at link following extract
"Analysis by the US Department of Energy (DoE) - seen by Newsnight - shows that at $50 a barrel Venezuela - not Saudi Arabia - will have the biggest oil reserves in Opec.
Venezuela has vast deposits of extra-heavy oil in the Orinoco. Traditionally these have not been counted because at $20 a barrel they were too expensive to exploit - but at $50 a barrel melting them into liquid petroleum becomes extremely profitable.
The DoE report shows that at today's prices Venezuela's oil reserves are bigger than those of the entire Middle East - including Saudi Arabia, the Gulf states, Iran and Iraq.
Venezuela's deposits alone could extend the oil age for another 100 years.
...
Mr Chavez told Newsnight that "Venezuela has the largest oil reserves in the world. In the future Venezuela won't have any more oil - but that's in the 22nd Century."
He will ask the Opec meeting in June to formally accept that Venezuela's reserves are now bigger than Saudi Arabia's."