The Tiber Oil Field is a deepwater offshore oil field located in the Keathley Canyon block 102 of the United States sector of the Gulf of Mexico. The deepwater field was discovered in September 2009 and it is operated by BP. Described as a "giant" find, it is estimated to contain 4 to 6 billion barrels of oil in place. Although BP states it is too early to be sure of the size – a "huge" field is usually considered to contain 250 million barrels. It required the drilling of a 10,685 m (35,056 ft) deep well under 1,260 m (4,130 ft) of water, making it one of the deepest wells ever drilled at the time of discovery.

Deepwater Horizon was an ultra-deepwater, dynamically positioned, semi-submersible offshore drilling rig owned by Transocean and operated by BP. On 20 April 2010, while drilling at the Macondo Prospect, a blowout caused an explosion on the rig that killed 11 crewmen and ignited a fireball visible from 40 miles (64 km) away. The fire was inextinguishable and, two days later, on 22 April, the Horizon sank, leaving the well gushing at the seabed and turning into the largest marine oil spill in history.