Buenos Aires, 22 August

A major, preliminary magnitude 7.5 earthquake struck in the South Atlantic Ocean late Thursday, the United States Geological Survey reported, prompting Chilean authorities to issue an advisory for a potential tsunami along parts of Antarctica. There were no evacuation orders immediately declared for Chile or Argentina, the two countries closest to the quake.

The temblor happened at 11.16 pm local time in Argentina about 710 kilometres southeast of Ushuaia, Argentina, in the Drake Passage, according to the US Geological Survey. The earthquake had a preliminary depth of 10.8 kilometres.

The Drake Passage connects the South Atlantic and South Pacific oceans between the southern tip of South America and the Antarctic Peninsula.

Though less quake-prone than other stretches of Chile's coast, the Drake Passage straddles a highly active seismic and geological zone.

The area is very remote and there were no immediate reports of damage or casualties.