MAP | 12 of the worst oil spills
A history of oil disasters from the 1978 Amoco Cadiz spill to the Deepwater Horizon in 2010.
An explosion on the Deepwater Horizon oil rig in the Gulf of Mexico on April 20, 2010 led to the largest offshore oil spill in history. On the fifth anniversary, here's a look at some of the worst oil spill disasters since 1978. The map below shows the magnitude of each spill, measured in tonnes of oil.