Gulf of Mexico oil spill burn-off. Slick of oil burning with thick oily smoke in the Gulf of Mexico, off the coast of Louisiana, USA. A boat at lower left provides a scale for this controlled burn. This oil spill was caused by an explosion and fire that destroyed the Deepwater Horizon oil rig in the Gulf of Mexico on 20 April 2010. Over the next three months, some 4.9 million barrels of oil welled up from the seabed into the Gulf of Mexico. The oil well was capped on 15 July 2010. The spill took place close to the coast of Louisiana, USA, where it caused extensive damage to wildlife and local fishing industries. Photographed on 9 June 2010.