A powerful earthquake measuring 8.8 on the Richter scale struck north-eastern Japan at 1446 local time (0546 GMT) on 11 March 2011. Initial estimates put the epicentre at 400km from Tokyo under the Pacific, at a depth of at a depth of 30km.
This was followed up with a devasting Tsumani. The (US) National Oceanic and Atmospheric Administration (NOAA) has published Tsunami warnings for the U.S. West Coast, Alaska, and British Columbia coastal regions, with a map forecasting Tsunami propagation energy and maximum wave amplitude for every country with a Pacific coastline:
And a map showing estimated impact times: