環太平洋火山帯で48時間に69回もの強い地震発生 
http://www.dailymail.co.uk/sciencetech/article-6081935/Is-Big-One-hit-California-Fears-rise-swarm-53-major-earthquakes.html
https://pbs.twimg.com/media/DlIbUXdU8AEvmi9.jpg