Blowouts and oil spills from offshore oil rigs, including those in the Gulf of Mexico, are all too common.
Last year there was a blowout, similar to that in the Gulf, involving the West Atlas drilling rig off north west Australia. The oil slick formed extended for more than 100 miles.
In the Gulf of Mexico three million gallons of oil spilled from offshore rigs over the period 1980 to 1999, with 18 wells having blowouts between 1983 and the latest accident. Some 80 oil workers died.