Beyond the strait: why Middle East oilfield shutdowns threaten to keep prices high

Oil could pass 2008 record of $147.50 a barrel as damage and closures risk compounding supply shock caused by Iran war

The world's largest offshore oilfield stretches more than 40 miles from Saudi Arabia's eastern province into the depths of the Persian Gulf. For almost 70 years the Safaniya field has produced millions of barrels of Arabian heavy crude to be sold by the biggest oil-producing country. This week, the field was shut.

The war in Iran has effectively blocked the Gulf states from exporting a fifth of the world's oil supply to the international buyers through the strait of Hormuz. Iran's attacks on tankers trapped in the vital trade route have erased an estimated 15m barrels of oil from the global market.