Ixtoc I oil spill
1979 CE.
Shown on the map at 19.414°, -92.331°.
Ixtoc I was an exploratory oil well being drilled by the semi-submersible drilling rig Sedco 135 in the Bay of Campeche of the Gulf of Mexico, about 100 km (62 mi) northwest of Ciudad del Carmen, Campeche in waters 50 m (164 ft) deep. On 3 June 1979, Ixtoc I suffered a well blowout resulting in the largest oil spill in history at its time. To-date, it remains the second largest marine oil spill in history after the Deepwater Horizon oil spill.
Text from the Wikipedia article Ixtoc I oil spill, licensed CC BY-SA 4.0.