The 2011 earthquake off the Pacific coast of Tōhoku (東北地方太平洋沖地震 Tōhoku-chihō Taiheiyō Oki Jishin?) was a magnitude 9.0–9.1 (Mw) undersea megathrust earthquake off the coast of Japan that occurred at 14:46 JST (05:46 UTC) on Friday 11 March 2011,[7][8][9] with the epicentre approximately 70 kilometres