Experts warn Japan may have entered an era of great earthquakes and volcanic eruptions

    

Mt. Fuji is located only about 25 kilometers from Mt. Hakone. While Mt. Fuji is also an active volcano, will the increased volcanic activity of Mt. Hakone have any effects on Mt. Fuji?

"The magma chambers located beneath Mt. Hakone and Mt. Fuji are not connected, so there is no effect on Mt. Fuji," said Toshitsugu Fujii, who chairs the Japan Meteorological Agency's Coordinating Committee for Prediction of Volcanic Eruptions. The agency has not observed any signs of impending eruption in Mt. Fuji and therefore has not raised the eruption alert level for the mountain.

However, since the magnitude-9.0 Great East Japan Earthquake occurred in March 2011, volcanoes in the country have shown signs of increased activity. Currently, a Level 2 eruption alert, which restricts access around the volcanic vent, is in effect for 10 volcanoes, while a Level 3 alert, which restricts approach to the volcano, has been issued for three volcanoes.

Meanwhile, on Sakurajima island in Kagoshima Prefecture, there have been 505 explosive eruptions this year, as of 6 p.m. Thursday, a number already exceeding last year's.

In light of the situation, Fujii said, "Japan might have entered an era of great earthquakes and volcanic eruptions" because, in the past, there have been large-scale volcanic eruptions before or after major earthquakes around the world.

For example, a massive magnitude-9.1 earthquake occurred off Sumatra, Indonesia, in 2004, and nearby Mt. Merapi erupted about one year later. In Japan, in 1707 during the Edo period, the Hoei Earthquake with a magnitude of 8.6 occurred in the Nankai Trough, and Mt. Fuji erupted 49 days after that.

"Since the beginning of the 20th century, Japan's active volcanoes have been too quiet," Fujii said. "As there have been signs of increased volcanic activity, it is necessary to keep alert not just on Mt. Hakone, but on other volcanoes as well."