Earthquake Sound of the Mw9.0 Tohoku, Japan earthquake (Zhigang Peng)

The Japan earthquake was recorded by two of the world's densest strong motion seismic networks, namely the K-Net and the Kik-Net. The example showing here was recorded by the K-Net station MYG004, which has the highest peak ground acceleration (PGA) of up to 3 g. This near-field recording show clearly two groups of ground motion, suggesting at least two patches of high-frequency radiation from the mainshock rupture. The highest PGA occurred at around 90 s, and the frequency and sound is quite different than the rest group, indicating that the source of such high-frequency radiation is likely very close to this station.

http://geophysics.eas.gatech.edu/people/zpeng/Japan_20110311/index.html