A 7.1-magnitude earthquake struck off the southern coast of Japan, prompting a tsunami advisory for Kyushu and Shikoku. Authorities are checking for damage, including at nuclear plants, with reports of minor damage at Miyazaki airport. A 7.1-magnitude earthquake struck off the southern coast of Japan, prompting a tsunami advisory for Kyushu and Shikoku. Authorities are checking for damage, including at nuclear plants, with reports of minor damage at Miyazaki airport.