The quake was not so bad in Tokyo

There was a pretty big quake in Niigata, about 150 miles north of Tokyo. It was a strong 6 on the Japanese scale, which suggests there may be structural damage in Niigata.

The Japanese scale is a measure of actual shaking at the surface, so it is a better indicator of damage than magnitude. While magnitude does tell you how big a quake is, it does not tell you how deep it is. There are many quakes with magnitudes of 8 or even 9, but if they happen deep under the ground, the shaking at the surface may not be very bad.

Initial reports by the BBC made it sound as if a 6.6 quake happened in Tokyo. The shaking here was moderate, and some people in Tokyo said "What quake?"

Depending on how your software is set up, you can see a short video clip of some of the damage at

http://www.yomiuri.co.jp/dy