The 2011 earthquake off the Pacific coast of Tōhoku (Tōhoku-
chihō Taiheiyō Oki Jishin), often referred to in Japan as
Higashi nihon daishin-sai and also known as the 2011 Tohoku
earthquake, the Great East Japan Earthquake, and the 3.11
Earthquake, was a magnitude 9.03 (Mw) undersea megathrust
earthquake off the coast of Japan that occurred at 14:46 JST
(05:46 UTC) on 11 March 2011, with the epicentre approximately
70 kilometres (43 mi) east of the Oshika Peninsula of Tōhoku and
the hypocenter at an underwater depth of approximately 32 km (20
mi). It was the most powerful known earthquake ever to have hit
Japan, and one of the five most powerful earthquakes in the
world since modern record-keeping began in 1900. The earthquake
triggered powerful tsunami waves that reached heights of up to
40.5 metres (133 ft) in Miyako in Tōhoku's Iwate Prefecture, and
which, in the Sendai area, travelled up to 10 km (6 mi) inland.
The earthquake moved Honshu (the main island of Japan) 2.4 m (8
ft) east and shifted the Earth o