Please note: In many cases, the station position in our database is accurate
to only one minute. Thus, the tide gauge may not appear to be on the coast.
A massive earthquake magnitude 9.0 occurred at 14.46 JST (05.46 UTC) on Friday 11th March 2011 with the epicentre situated approx. 70km east of the Oshika Peninsula of Tohoku. It was the most powerful earthquake ever to hit Japan triggering a tsunami with waves of up to 40.5m high and travelling up to 10km inland.
Data Authority
Japan Oceanographic Data Centre Hydrographic Department, Maritime Safety Agency MLIT Aomi Building 2-5-18, Aomi, Koto-ku Tokyo 135-0064