摘要：On 3 September 2017 official channelsof the Democratic People's Republic of Korea announced the successful test ofa thermonuclear device. Only seconds to minutes after the alleged nuclearexplosion at the Punggye-ri nuclear test site in the mountainous region inthe country's northeast at 03:30:02 (UTC), hundreds of seismic stationsdistributed all around the globe picked up strong and distinct signalsassociated with an explosion. Different seismological agencies reported bodywave magnitudes of well above 6.0, consequently estimating the explosiveyield of the device on the order of hundreds of kT TNT equivalent. The2017 event can therefore be assessed as being multiple times larger in energythan the two preceding North Korean events inJanuary and September 2016. This study provides a multi-technology analysis of the 2017 North Korean eventand its aftermath using a wide array of geophysical methods. Seismologicalinvestigations locate the event within the test site at a depth of approximately0.6km below the surface. The radiation and generation of P- and S-wave energy inthe source region are significantly influenced by the topography of the Mt.Mantap massif. Inversions for the full moment tensor of the main event reveal adominant isotropic component accompanied by significant amounts of double coupleand compensated linear vector dipole terms, confirming the explosive characterof the event. The analysis of the source mechanism of an aftershock that occurredaround 8min after the test in the direct vicinity suggest a cavitycollapse. Measurements at seismic stations of the International MonitoringSystem result in a body wave magnitude of 6.2, which translates to an yieldestimate of around 400kT TNT equivalent. The explosive yield is possiblyoverestimated, since topography and depth phases both tend to enhance the peakamplitudes of teleseismic P waves. Interferometric synthetic aperture radaranalysis using data from the ALOS-2 satellite reveal strong surface deformationsin the epicenter region. Additional multispectral optical data from the Pleiadessatellite show clear landslide activity at the test site. The strong surfacedeformations generated large acoustic pressure peaks, which were observed asinfrasound signals with distinctive waveforms even at distances of 401km. Inthe aftermath of the 2017 event, atmospheric traces of the fission product133Xe were detected at various locations in the wider region. Whilefor 133Xe measurements in September 2017, the Punggye-ri test site isdisfavored as a source by means of atmospheric transport modeling, detections inOctober 2017 at the International Monitoring System station RN58 in Russiaindicate a potential delayed leakage of 133Xe at the test site from the2017 North Korean nuclear test.
