North Korea's nuclear blasts have turned Mount Mantap into a persistent quake zone

A recent paper published in Science reports that North Korea's Mount Mantap, also known as Mantapsan, is experiencing a marked increase in earthquakes due to the country's series of underground nuclear tests. Seismologist Kwang-Hee Kim of Pusan National University explains that each blast progressively weakens the surrounding rock and alters stress on pre-existing faults. The 2017 test, estimated at 100-250 kilotons, caused the most severe damage, collapsing the mountain's summit and setting off a chain reaction of fault disturbances.

Between 2008 and 2025, researchers counted nearly 1,400 quakes, with a sharp uptick in both magnitude and frequency after the 2017 event. Columbia University seismologist Paul Richards, not involved in the study, calls the findings “potentially dangerous,” noting the risk of larger future quakes. The damage has rendered the peak unsuitable for further testing, though other sites at the Punggye-ri complex may still be used. Persistent seismicity could also blur the line between nuclear-related and natural earthquakes, hampering international verification efforts.