It triggered a tsunami warning for Cuba, Jamaica and the Cayman Islands, the US Geological Survey and the International Tsunami Information Centre said.
The quake, initially reported as a magnitude 7.3 before being upgraded, was centred in the sea between Jamaica, the Cayman Islands and Cuba, at a shallow depth of 10 kilometres.
"Hazardous tsunami waves from this earthquake are possible within 300km of the epicentre along the coasts of Jamaica … Cayman Islands and Cuba," the International Tsunami Information Centre said.
