Honshu 9.0

Figure 1 - FFT Showing Earth Ringing from Honshu 9.0 Earthquake
 
Figure 1 is a plot of a Fast Fourier Transform from 60 minutes of Inyo seismometer recorded data. Data was recorded about 12 hours after the 9.0 earthquake. Time period did not include any observable aftershocks. Notice the defined peaks. Click plot to expand size.