Major temblor could trigger Fuji eruption


The iconic, 3,776-meter-high Mount Fuji may violently erupt if a major earthquake were to rip open its magma chamber, according to a team of researchers.

The researchers include those from the state-run National Institute of Advanced Industrial Science and Technology, or AIST.

Mount Fuji, which was registered on UNESCO’s list of World Heritage cultural sites last month, is an active stratovolcano that last erupted in 1707 in what is known as the Hoei eruption, which dumped a large amount of volcanic ash onto the Kanto region, centering on what is now Tokyo.

The researchers warn of another possible violent eruption of Mount Fuji, noting the pressure in its magma chamber has been building for the past 300 years and a massive temblor nearby could cause this to be explosively released, the researchers said.

The team looked into a number of craters on the mountain through aerial photos and field investigations to analyze past eruptions between some 10,000 years ago and the 1707 eruption.

The study showed that a large number of surface rock formations created before the 1707 eruption have prevented magma from rising.

But in the case of the Hoei eruption, two major earthquakes with a magnitude of 8 hit Mount Fuji, in 1703 and 1707, causing magma under the surface to rise.

Volcanologist Akira Takada warned that a major temblor, such as the forecast mega-quake along the Nankai Trough, could trigger a Mount Fuji eruption.

  • Sugar

    Now that Mt. Fuji have been registered as UNESCO World Heritage Site recently, so if the eruption occurred in this timing, it would feel very sad..
    I hope there’re a good news about Mt.Fuji.

  • This strikes me as gross speculation by academic geologists perhaps cynical about their lack of standing compared to pop idols. They will need more evidence that that mere correlation. Faults in the context of intrusive events are as much annealing as ‘weakening’ events. Only if this was an exogenous tectonic issue would this be a consideration, and that is precisely what these volcanic structures are not. Faulting in the context of volcanoes is related to the emplacement of magma, and there is a balance, only broken by pressure build-up (i.e. inflation) or failure like Mt St Helens. They allude to no such weakness or build-up. Is there a major tectonic structure passing through Mt Fuji? A quake along the Nankai Trough would reduce pressure upon Honshu (Asia Plate), not increase it. The implication is that an eruption of Mt Fuji would be in spite of such an earthquake. The best evidence for a Mt Fuji eruption would come from chamber inflation and relative measurements of ground movement in Honshu (as a measure of chamber compression), not earthquakes at the juncture of two plates.
    Anyway speculation is good if it contributes to critical ‘conceptual’ insight. The problem with science is often the over-reliance upon empirical data at the expense of conceptual frameworks. Geology is a complex story. Its easy to speculate, fear-monger, but in the long run, this serves only scepticism about science.

    • Masa Chekov

      “The problem with science is often the over-reliance upon empirical data at the expense of conceptual frameworks.”

      Oh, I’d go the other way. Many times the conceptual framework is way in front of any empirical data to support it. That’s fine in the case of theoretical physics, not so good for geology.

      • Well, scientists are so specialised, so the problem with empiricism is the lack of conceptual development. Yes, the alternate of ‘rationalism’ is just as problematic, and that is true of theoretical physics simply because people are speculating with limited data. You could also argue that the lack of conceptual ‘intrigue’ contributes to the lack of collection of data, i.e. Global warming & the Christchurch earthquake – might we have been better prepared if we had more respect for ideas (not detached from evidence) and politicians concerned only with popular perceptions.