My first earthquake..

On our last morning in Japan I lay in my bed in Hotel Mystays in Tokyo with a slight hangover, though I am convinced this was mostly due to mixing cold and flu tablets with alcohol and not the amount of alcohol I had consumed. I stirred to the gentle rocking of the bed and the awkward movements of my body as it tried to move at the same rythm. In a sleepy and confused daze I wondered if I was in one of those vibrating beds you see in the movies in American motels. After all we were in Japan -the land of warm toilet seats and bullet trains so why not?

What I discoverd later was that I had experienced my first earthquake. It hit at 6:51 a.m. local time about 170 kilometers northeast of Tokyo, east of Japan at a depth of about 35 kilometers (21.7 miles), according to the U.S. Geological Survey. It was magnitude 5.8 on the Richter Scale.

For thoses non-geologists (and geologists that have forgotten), the Richter magnitude scale ranges from 0 to 10 and quantifies the amount of seismic energy released by an earthquake. It is a base-10 logarithmic scale which means that an earthquake that measures 6.0 on the Richter scale has a shaking amplitude 10 times greate than one that measures 4.0. According to the scale, an earthquake within the range of 5.0-5.9 (like that experienced on 1 Feb in Tokyo) is of moderate magnitude and can cause major damage to poorly constructed buildings over small regions. At most slight damage to well-designed buildings. There are approximately 800 of these types of earthquakes every year. Luckily for us and all those living in Japan there were no reported damage from this quake.

Seismograph taken from Channelnewsasia.com