The source parameter of the Northwestern Kagoshima earthquakes

(May 13,1997.Mjma 6.2)


<Shimabara Earthquake and Volcano Observatory>

The source parameter presumed from the vertical displacement waveform of STS-2 seismograph of the Fukue Earthquake Observatory, Kyushu University (FUK) is as follows.

Seismic Moment
Mo 1.2~10^18 mE

Moment Magnitude
Mw 6.0

These shows that the scale of the earthquake was almost of the same grade as the earthquake on March 26,1997 (Mjma6.3).

From the seismic waveform of the following figure, it is surmised by this earthquake that at least three fault rupture occurred in 8.1 seconds.

According to the aftershock distribution, it can be said that this earthquake is considered that fault rupture progressed to the both directions of the direction of north and south, and is a very rare earthquake. This detailed focus process is under analysis now.