Updated Oct. 27, 2014, The Japan Times: ” Japan could be nearly destroyed by a volcanic eruption over the next century that would put nearly all of its population of 127 million people at risk, a new study says.
“It is not an overstatement to say that a colossal volcanic eruption would leave Japan extinct as a country,” Kobe University earth sciences professor Yoshiyuki Tatsumi and associate professor Keiko Suzuki said in the study, released publicly on Wednesday.
The experts said they analyzed the scale and frequency of volcanic eruptions throughout the archipelago over the past 120,000 years and calculated that the odds of a devastating eruption at about 1 percent over the next 100 years.
The chance of a major temblor striking Kobe within 30 years was estimated at about 1 percent just a day before a 7.2-magnitude quake struck the port city in 1995, killing 6,400 people and injuring nearly 4,400 others, the study noted.
“Therefore, it would be no surprise if such a colossal eruption occurs at any moment,” it added.
The Kobe University researchers said their study is critical because Japan is home to about 7 percent of the volcanoes that have erupted over the past 10,000 years.
A disaster on Kyushu, which has been struck by seven massive eruptions over the past 120,000 years, would see an area with 7 million people buried by flows of lava and molten rock in just two hours, they said.
Volcanic ash would also be carried by westerly winds toward the main island of Honshu, making nearly the entire country “unlivable” as it strangled infrastructure, including key transport systems, they said.
It would be “hopeless” trying to save about 120 million living in major cities and towns across Honshu, the study said.
The study called for new technology to more accurately grasp the state of the “magma reservoirs” that are spread across the Earth’s crust in layers a few kilometers deep. ”
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Posted Oct. 24, 2014: ” (Reuters) – Japan warned on Friday that a volcano in southern Japan located roughly 64 km (40 miles) from a nuclear plant was showing signs of increased activity that could possibly lead to a small-scale eruption and warned people to stay away from the summit.
The warning comes nearly a month after another volcano, Mt Ontake, erupted suddenly when crowded with hikers, killing 57 people in Japan’s worst volcanic disaster in nearly 90 years.
Ioyama, a mountain on the southwestern island of Kyushu, has been shaken by small tremors and other signs of rising volcanic activity recently, including a tremor lasting as long as seven minutes, an official at the Japan Meteorological Agency’s volcano division said.
“There is an increase in activity that under certain circumstances could even lead to a small scale eruption, but it is not in danger of an imminent, major eruption,” the official said.
The warning level on the mountain has been raised from the lowest possible level, normal, to the second lowest, which means that the area around the crater is dangerous, he added.
Ioyama lies in the volcanically active Kirishima mountain range and is roughly 64 km from the Sendai nuclear plant run by Kyushu Electric Power Co, which the Japanese government wants to restart even though the public remains opposed to nuclear power following the Fukushima crisis.
Critics point out that the Sendai plant is located about 50 kms (31 miles) from Mount Sakurajima, an active volcano that erupts frequently. Five giant calderas, crater-like depressions formed by past eruptions, are also in the region, the closest one 40 kms (25 miles) away.
The plant still needs to pass operational safety checks as well as gain the approval of local authorities and may not restart till next year.
Before giving its initial greenlight to restart the plant in July, the Nuclear Regulation Authority (NRA) said the chance of major volcanic activity during the lifespan of the Sendai nuclear plant was negligible.
On Friday, the warning level for the Sakurajima volcano, which erupts frequently, was at 3, which means that people should not approach the peak.
Japan lies on the “Ring of Fire” – a horseshoe-shaped band of fault lines and volcanoes around the edges of the Pacific Ocean – and is home to more than 100 active volcanoes.
Experts warn that the mammoth 9.0 March 2011 quake may have increased the risk of volcanic activity throughout Japan, including that of iconic Mount Fuji. ”