JMA has
deployed about 400 seismic intensity meters through out Japan
(Nishimae,2004). The seismic intensity meters record the
ground acceleration and calculate the seismic intensity. The
seismic intensity and the PGA of the components (NS,EW
and UD) are usually published immediately after an earthquake. Although the acceleration records with large amplitudes are also open to the public, the ground profile has not
been published. The epicenters of the aftershocks are also
plotted in Fig.3 so as to display the main shock fault area.
The high PGA area is concentrated in the northern part where
the aftershocks occurred.