Identification of Seismic Events on and near the North Korean Test Site after the Underground Nuclear Test Explosion of 3 September 2017

Abstract

Research Article| September 19, 2018 Identification of Seismic Events on and near the North Korean Test Site after the Underground Nuclear Test Explosion of 3 September 2017 Won‐Young Kim; Won‐Young Kim aLamont‐Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, New York 10960 U.S.A., wykim@LDEO.columbia.edu Search for other works by this author on: GSW Google Scholar Paul G. Richards; Paul G. Richards aLamont‐Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, New York 10960 U.S.A., wykim@LDEO.columbia.edu Search for other works by this author on: GSW Google Scholar David Schaff; David Schaff aLamont‐Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, New York 10960 U.S.A., wykim@LDEO.columbia.edu Search for other works by this author on: GSW Google Scholar Eunyoung Jo; Eunyoung Jo bEarthquake and Volcano Monitoring Division, Korea Meteorological Administration, 61 16‐Gil Yeouidaebang‐Ro Dongjak‐Gu, Seoul 156‐720, Republic of Korea Search for other works by this author on: GSW Google Scholar Yonggyu Ryoo Yonggyu Ryoo bEarthquake and Volcano Monitoring Division, Korea Meteorological Administration, 61 16‐Gil Yeouidaebang‐Ro Dongjak‐Gu, Seoul 156‐720, Republic of Korea Search for other works by this author on: GSW Google Scholar Author and Article Information Won‐Young Kim aLamont‐Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, New York 10960 U.S.A., wykim@LDEO.columbia.edu Paul G. Richards aLamont‐Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, New York 10960 U.S.A., wykim@LDEO.columbia.edu David Schaff aLamont‐Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, New York 10960 U.S.A., wykim@LDEO.columbia.edu Eunyoung Jo bEarthquake and Volcano Monitoring Division, Korea Meteorological Administration, 61 16‐Gil Yeouidaebang‐Ro Dongjak‐Gu, Seoul 156‐720, Republic of Korea Yonggyu Ryoo bEarthquake and Volcano Monitoring Division, Korea Meteorological Administration, 61 16‐Gil Yeouidaebang‐Ro Dongjak‐Gu, Seoul 156‐720, Republic of Korea Publisher: Seismological Society of America First Online: 19 Sep 2018 Online Issn: 1938-2057 Print Issn: 0895-0695 © Seismological Society of America Seismological Research Letters (2018) 89 (6): 2120–2130. https://doi.org/10.1785/0220180133 Article history First Online: 19 Sep 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Won‐Young Kim, Paul G. Richards, David Schaff, Eunyoung Jo, Yonggyu Ryoo; Identification of Seismic Events on and near the North Korean Test Site after the Underground Nuclear Test Explosion of 3 September 2017. Seismological Research Letters 2018;; 89 (6): 2120–2130. doi: https://doi.org/10.1785/0220180133 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietySeismological Research Letters Search Advanced Search ABSTRACT Eleven small seismic events that occurred after the North Korean underground nuclear test (UNT) on 3 September 2017 have been reported. We detected three additional events not found using traditional methods by using a waveform‐matching technique. The magnitude of these fourteen shocks ranges from Mw 2.1 to 4.0. The first and largest of them, occurring about 8½ minutes after the nuclear explosion itself, has been identified by several authors as a cavity collapse. We analyzed the remaining 13 events, first by using regional P‐ and S‐wave spectral amplitude ratios observed at station MDJ (Mudanjiang, China), applying Mahalanobis methods to identify them. Applying a previously established linear discriminant function for the region to observed P/S spectral ratios, 12 of the events are classified as earthquakes, and 1 other, the first of a doublet pair on 9 December 2017, appeared to be an explosion. However, waveform similarity of this event with its doublet pair, and application of the MDJ discriminant function to data from two other regional stations suggests that it, too, is likely to be an earthquake. It appears that damage caused by strong ground motion from the large UNT of 3 September 2017 has led to slow adjustments in the surrounding region entailing stress relief via aftershocks. Additional small seismic events (earthquakes) may be expected in the region. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.