The closer to the colour red the spot is, the closer to the surface the quake focus was in this map of Japan. Image: Pacific Tsunami Warning Center.

Japan tremors incredibly close to the surface

Map shows how shallow the focus of earthquake is – red and orange spots denote shocks less than 25km from the surface.

THE CLOSER TO the surface the focus of the earthquake, the more damage it causes.

This morning’s 8.9 magnitude quake in Japan had its epicentre about 380km northeast of Tokyo, and its focus was 10km under the surfacem which is relatively shallow.

The Pacific Tsunami Warning Center, has just released this image of how the earthquake was felt in Japan. The closer to the red end of the colour spectrum the dots are, the closer to the surface the shock hit. Red is between 0-10km, orange from about 10-28km and green is around 100km. The blues denote that the focus was over 200km but no further than 600km under the surface of the earth.