Fig. 1. The location of the 30 Broadband stations used for source scaling is illustrated with blue triangle. The black square represents DRPK‘s Punggye-ri underground nuclear test site.
Fig. 2. An example of seismic waveform pairs from DPRK’s 5th and 6th underground nuclear tests is shown, which was the recording at the station CHNB. Top trace is the waveform recorded from the 5th test while bottom trace is the one from the 6th test. First 6.4 seconds of waveform is chosen for power spectrum calculation.
Fig. 3. Source scaling result is illustrated. Spectral ratios in green represent source scaling of the 30 pairs of vertical component from the 30 broadband stations while the ensemble median of these is shown with red.
Table 1. Bodywave magnitude (mb) estimates on the DPRK’s 5th an 6th nuclear tests
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