The eruption of Ontake, Japan’s second-tallest volcano, sent a column of ash and superheated steam six miles into the sky.
Ministry of Land, Infrastructure / AFP / Getty Images
In some areas, the fallen ash is more than 20 inches deep.
active volcanoes.
Researchers estimate that Japan has more than 100
Jim McMahon
Jim McMahon
OCTOBER 1, 2014
A Deadly Volcanic Eruption in Japan
The surprise explosion on Mount Ontake takes dozens of lives
BY HAILEE ROMAIN
Mount Ontake, a volcano in central Japan, erupted unexpectedly last Saturday. Officials responded as quickly as possible, but at
least 47 people are believed dead after the devastating event. Toxic gases, thick ash, and the possibility of another eruption made
recovery efforts challenging.
The colorful fall leaves in the area near the volcano draw many visitors every year. More than 250 hikers were on the slopes of the
mountain at the time of the eruption. About 200 people escaped to safety. Many were able to hurry down the mountain or take
shelter from falling rocks at lodges along the trails.
A SEISMIC SHOCK
Most of the time, scientists are able to predict when a volcanic eruption will happen and can give people plenty of warning to stay
away from the blast. But Ontake’s eruption came as a surprise. That’s because this particular kind of explosion is almost impossible
to predict.
There are different types of volcanic eruptions. The most powerful start deep within the Earth’s crust and spew hot lava, or molten
rock, into the air. Some, like that on Mount Ontake, occur when superheated steam underground explodes outward as the pressure
within the volcano becomes too great.
“If you have a monitoring system in place, it’s very unlikely that deeper activity will go unnoticed,” Philipp Ruprecht,
a volcanologist (a scientist who studies volcanoes), told CBS News. “[But] we have very little information or science to help the
monitoring people with [steam] eruptions.”
Weeks of minor earthquakes led up to the explosion, but seismologists (scientists who study the movement of Earth’s crust) didn’t
recognize them as warning signs.
The eruption of Ontake, Japan’s second-tallest volcano, sent a column of ash and superheated steam six miles into the sky. The ash
eventually fell to the ground and covered much of the mountain. In some areas, the fallen ash is more than 20 inches deep.
RING OF FIRE
This is the first time since 1991 that someone in Japan has died because of a volcanic eruption, even though Japan experiences a
lot of volcanic activity. Many researchers estimate that the country has more than 100 active volcanoes.
Why does Japan have so many volcanoes? The country is located in an area of the Pacific Ocean called the Ring of Fire. This
region is home to more than 75 percent of the world’s active and dormant volcanoes.
Earth’s surface is made up of slabs of rock called tectonic plates. When two plates collide or move apart, the motion can cause
earthquakes or volcanic eruptions. Plates slide and shift a lot in the Ring of Fire, which makes it a hotbed of volcanic activity.