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Seismic activity rises at Punggye-ri after 2017 test

By Drooid · Sep 18, 2026, 6:31 AM UTC · How we work

Summary

Researchers Detect Seismic Surge

Researchers found rising seismic activity at North Korea’s Punggye-ri test site after the September 2017 nuclear test.
Analysis of Chinese and South Korean records from 2008-2025 identified 1,399 unrecorded local earthquakes near Mount Mantap.
Seismicity began on September 23, 2017, three weeks after the test, and increased in frequency and magnitude through 2025.
Researchers recommend long-term monitoring of former test sites to separate natural from explosion-related quakes under the CTBT.

Summary

IAEA Reports Restoration

International Atomic Energy Agency reported tunnel restoration at Punggye-ri began in March 2022.
A 2025 Defense Intelligence Agency assessment said the nuclear test site was restored.
South Korean researchers documented radiation exposure among defectors living near the former test site.
Satellite radar measurements detected ground deformation atop Mount Mantap after the 2017 nuclear test.
Researchers said water infiltration into fractures could raise pore pressure, extending seismic activity after the 2017 test.

History

Historical Context

The 1996 Comprehensive Nuclear-Test-Ban Treaty, adopted by the United Nations and signed by 183 nations, prohibited all nuclear explosions. Following the treaty, the United States and the Soviet Union established the International Monitoring System, deploying over 3,200 seismic stations worldwide. Today, the treaty’s legacy mirrors current efforts to monitor North Korea’s Punggye-ri site, where IAEA and South Korean scientists track post-2017 quakes. Continued seismic surveillance aims to differentiate natural tremors from clandestine tests, reinforcing global non-proliferation enforcement and future treaty verification.

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Researchers Detect Seismic Surge

Researchers found rising seismic activity at North Korea’s Punggye-ri test site after the September 2017 nuclear test.
Analysis of Chinese and South Korean records from 2008-2025 identified 1,399 unrecorded local earthquakes near Mount Mantap.
Seismicity began on September 23, 2017, three weeks after the test, and increased in frequency and magnitude through 2025.
Researchers recommend long-term monitoring of former test sites to separate natural from explosion-related quakes under the CTBT.

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