On 3.11.11 an earthquake attacked the coast of
http://topics.nytimes.com/top/news/international/countriesandterritories/japan/index.html?scp=1-spot&sq=japan%20earthquake&st=cse
Widespread destruction from Japan earthquake, tsunamis
The disaster's massive impact was only beginning to be revealed.
A 30-foot wall of water swept across rice fields. It engulfed all of the towns, dragged houses onto highways, and tossed cars and boats like toys. Some waves reached six miles (10 kilometers) island in Miyagi Prefecture on Japan's east coast.
http://www.travelingtrees.com/japan-land-of-the-rising-sun
Japan earthquake: How Tokyo got an 80-second head start
The earthquake began at 5:46 GMT. It took 10 seconds for sensors to detect enough signals to conclude that the earthquake was serious & issue the alerts. Since the more damaging secondary waves traveled at 4 kilometers per second, it took 90 seconds to travel the 373 kilometers to Tokyo, Rondenay says. Many homes and buildings had been destroyed.