The third largest crude oil producer in Africa, Angola joined OPEC in January 2007 as the oil cartel's 12th member. The West African nation primarily flares its natural gas but is furthering plans to convert the energy commodity into liquefied natural gas (LNG). As of January 2008, Angola's proven oil reserves totaled 9 billion barrels, the majority of which are located in the country's offshore blocks. Overseen by state-controlled Sonangol, oil majors BP, Chevron, ExxonMobil and Total are all developing upcoming deepwater projects in the offshore Angolan region, with expected start-up dates spanning to 2011.