The 2011 Tōhoku earthquake and tsunami was a 9.0-magnitude undersea megathrust earthquake off the coast of Japan that occurred at 14:46 JST on Friday, 11 March, 2011. The epicenter was approximately 72 kilometers east of the Oshika Peninsula of Tōhoku, with the hypocenter at an underwater depth of approximately 32 km.
The earthquake triggered extremely destructive tsunami waves of up to 23.6 m that struck Japan minutes after the quake, in some cases traveling up to 10 km inland, with smaller waves reaching many other countries after several hours. Tsunami warnings were issued and evacuations ordered along Japan’s Pacific coast and at least 20 other countries, including the entire Pacific coast of North America and South America.