North Korea’s underground nuclear weapon blasts may be accidentally destabilizing a deadly volcano. Mount Paektu has been known to catastrophically erupt in the past, and according to a new study in Scientific Reports, powerful tremors produced by these military tests may be waking this sleeping dragon.
The world’s most secretive state has conducted a series of nuclear tests in the last decade, causing concern in the global community. Although they do not yet have the capability to launch these missiles across international borders, an eruption at Paektu, which lies on the Chinese-North Korean border, could potentially cause an international disaster.
The last test, which was claimed on North Korean television to be a hydrogen bomb detonation – although this was refuted by a large number of experts – registered as a magnitude 5.1 earthquake. Pressure waves generated by the blast travelled outwards in all directions, including towards the magma source beneath Paektu 116 kilometers (72 miles) away. In this new study, a team of South Korean researchers note that these kinds of waves can disturb magma that is already under considerable pressure deep underground.
A volcano explosively erupts when the internal pressure of the magma overcomes the confining pressure of the surrounding rock. At this point, the rock cracks and the roof of the chamber collapses, causing a sudden depressurization event and an uprush of magma and gas.
Using a series of mathematical models, the researchers calculated that if a more powerful underground nuclear bomb test was conducted, one that would register as a magnitude 7 earthquake, it would cause the internal pressure of the magma chamber to rise. Worryingly, this increase in pressure would be just enough to trigger an eruption.
The crater lake at the top of the volcano. Bdpmax/Wikimedia Commons; CC BY-SA 3.0
The volcano – known in Mandarin Chinese as Changbaishan – last erupted in 1903, although the Millennium Eruption in the year 946 was, by a huge margin, the most devastating. Blasting out around 100 cubic kilometers (24 cubic miles) of lava, ash and volcanic bombs, it may have also released as much energy as 100 million “Little Boy” atomic bombs that devastated Hiroshima. The 1980 eruption of Mount St. Helens in Washington State, itself a highly destructive eruption, was 1,000 times less powerful.
The volcano is currently showing signs of unrest, and the few volcanologists from around the world that have been allowed access to the site are increasingly worried. Upticks in seismic activity, indicating magma moving through the crust, have been recorded since 2002; additionally, increased sulfur dioxide gas emissions at the surface suggest that the pressure inside the magma chamber is building.
A repeat of the Millennium Eruption, one of the most powerful in human history, would annihilate the surrounding landscape, and could cause global climatic changes. Based on recent satellite images, North Korea may already be planning to carry out a fifth underground nuclear test – could this be the one to awaken it?