“How much oil lies beneath the desert sands of Saudi Arabia and how long will it last before running out?” is a question that has intrigued and confounded oil experts for five decades. The kingdom has proven reserves of 266 billion barrels according to government estimates submitted to the Organization of the Petroleum Exporting Countries (“Annual Statistical Bulletin”, OPEC, 2015). If these numbers are correct, Saudi Arabia’s reserves will last for another 70 years at the average production rate of 10.2 million barrels per day reported for 2015. But there is widespread scepticism about the official estimates, which were abruptly raised without explanation from 170 billion barrels in 1987 to 260 billion in 1989 ( tmsnrt.rs/29fzTm3 ). Official reserves have remained constant every year since then at 260-265 billion barrels, even […]