Z. Liu¹

¹CTBT Beijing National Data Center and Beijing Radionuclide Laboratory

Abstract:

Doubtful earthquake events in Standard Screened Event Bulletins of the International Data Center are focus events to every states signatories. The complexity of waveform, spectral ratio, and composite ratio were selected as the three criteria for discrimination of nuclear explosions from earthquakes. A method has been developed using the difference between the focal mechanisms and the study of multi-criteria synthetic methods. The three criteria and multi-criteria synthetic method were applied to six nuclear explosions and five natural earthquakes, which happened in Punggye-ri nuclear test site of North Korea. The results of application indicated that multi-criteria synthetic method came to an accurate conclusion for these events, even if one of the criteria provided a wrong decision, which verified the effectiveness of multi-criteria synthetic method.