New evidence for molten rock beneath Changbaishan/Mt. Paektu volcano
Birkbeck’s Dr James Hammond says that monitoring the volcano and the surrounding region together with detailed study of past eruptions is vital in order to understand and predict its activity.
New research led by Birkbeck’s Dr James Hammond indicates the presence of molten rock beneath the Changbaishan/Mt. Paektu volcano, which was responsible for one of the largest volcanic eruptions in known history - the ‘Millenium Eruption’ of 946 CE.
The volcano sits in the China/Korean peninsula. This study was the first cross-border study of the region, and therefore represents a unique scholarly collaboration between the UK, China and the Democratic People’s Republic of Korea (DPRK - the formal name for North Korea). This is especially significant as prior studies of the region have relied on data from either China or the DPRK, while a cross-border approach means datasets can be integrated, and a fuller picture is available.
Using data from both China and DPRK, Dr Hammond and his colleagues from Beijing, Pyongyang and Cambridge examined the crustal structure underneath the volcano. They found a sharp velocity reduction approximately 7km beneath the volcano, extending approximately 30km the volcano’s base.
The scientists say this suggests the presence of molten rock beneath the base of Changbaishan/Mt. Paektu, which may have been recharged during a period of volcanic unrest between 2002-2005. This period was characterised by increased seismicity, surface deformation and volcanic gas emissions. While no eruption occurred at this time, the unrest sparked renewed interest in the volcano as it showed it to still be active.
This new evidence of an active magmatic system highlights the importance of sustained operational surveillance going forward.
Dr Hammond said: “Our findings provide supporting evidence for the presence of a magma reservoir beneath Changbaishan/Mt. Paektu. Monitoring the volcano and the surrounding region together with detailed study of past eruptions is vital in order to understand and predict its activity, including the risk of future eruptions. Importantly, while the top of this region is well constrained, its base is not. In the low velocity zone we uncovered, little structure is evident, suggesting that partial melt may be present throughout the crust.
“The thickened crust and evidence for shallow velocities that we can see under Changbaishan/Mt. Paektu are also evident beneath neighbouring volcanoes, meaning they may also sit above magmatic systems. More research is needed to uncover whether this is indeed the case.”