Small earthquakes tremble the ground
below Mount St. Helens volcano
By Alan Yuhas, The Guardian, adapted by Newsela staff on 05.16.16
Word Count 338
Mount St. Helens in Washington state emits a plume of steam and ash, Oct. 1, 2004. Photo: REUTERS/U.S. Navy/Scott
Taylor HB
In 1980, Mount St. Helens erupted. The volcano is in Washington state. It was the worst
eruption in United States history. Scientists say the volcano may be getting ready to blow
again. It probably will not happen for years, though.
In the last two months, there have been more than 130 earthquakes under the volcano.
The information comes from the U.S. Geological Survey (USGS). The government
department studies the earth.
Since March, the number of earthquakes has been increasing, the USGS said. Almost 40
earthquakes were found in one week.
Many Quakes Were Too Weak To Measure
Most of the quakes took place far below the volcano. Most have been very weak. They
were at magnitudes of 0.5 or less. The largest was a 1.3-level quake. Magnitude measures
how strong an earthquake is. It rates earthquakes on a scale of 1 to 10.
The USGS said there had been more earthquakes. They were too small to be felt.
The volcano is not likely to erupt soon, the USGS said. Earthquakes often take place under
volcanoes.
The earthquakes probably mean that magma is building up under the volcano. Magma is
very hot rock. It comes from deep inside the Earth. As magma rises to fill the volcano, it
presses against the colder rock around it. This push and pull creates quakes.
Mount St. Helens last erupted in 2008.
1980's Eruption Killed 57 People
The big eruption was May 18, 1980. It blew ash 80,000 feet in the air. The ash fell as far
away as New Mexico. Boiling ash, gas and rock flowed off the volcano's slopes. Part of the
volcano was destroyed. The eruption killed 57 people.
Scientists now check the volcano constantly. It is one of the most closely watched in the
world.
Seth Moran is the chief scientist at the Cascades Volcano Observatory. Mount St. Helens is
in the Cascade mountain range. He does not think the volcano will explode for many years.
When it does, Moran thinks it will not be as bad as 1980.
Quiz
1
2
3
4
Why do scientists think magma is building up under the volcano?
(A)
Many people are moving away from the volcano.
(B)
Hot rock has begun to come out of the top of the volcano.
(C)
Ash can be seen in the air high above the volcano.
(D)
Many little earthquakes have happened under the volcano.
What is the reason why scientists are always checking Mount St. Helens?
(A)
They believe the volcano will explode next year.
(B)
They think the volcano will explode for the first time.
(C)
They know the volcano can explode and hurt people, because it did before.
(D)
They want to stop the earthquakes around the volcano, because
earthquakes can hurt people.
With which opinion would the USGS scientists most likely AGREE?
(A)
It is safe to be near Mount St. Helens when it explodes.
(B)
Mount St. Helens could be a very dangerous volcano.
(C)
There is no good reason to study Mount St. Helens.
(D)
Mount St. Helens is not a very interesting volcano.
Read the last paragraph of the article.
Seth Moran is the chief scientist at the Cascades Volcano Observatory.
Mount St. Helens is in the Cascade mountain range. He does not think
the volcano will explode for many years. When it does, Moran thinks it
will not be as bad as 1980.
What is Seth Moran's point of view about Mount St. Helens?
(A)
The volcano will never erupt again.
(B)
The volcano will probably not erupt soon.
(C)
If the volcano erupts, many people will be killed.
(D)
If the volcano erupts, it will be worse than the first eruption.
Answer Key
1
2
3
4
Why do scientists think magma is building up under the volcano?
(A)
Many people are moving away from the volcano.
(B)
Hot rock has begun to come out of the top of the volcano.
(C)
Ash can be seen in the air high above the volcano.
(D)
Many little earthquakes have happened under the volcano.
What is the reason why scientists are always checking Mount St. Helens?
(A)
They believe the volcano will explode next year.
(B)
They think the volcano will explode for the first time.
(C)
They know the volcano can explode and hurt people, because it did
before.
(D)
They want to stop the earthquakes around the volcano, because
earthquakes can hurt people.
With which opinion would the USGS scientists most likely AGREE?
(A)
It is safe to be near Mount St. Helens when it explodes.
(B)
Mount St. Helens could be a very dangerous volcano.
(C)
There is no good reason to study Mount St. Helens.
(D)
Mount St. Helens is not a very interesting volcano.
Read the last paragraph of the article.
Seth Moran is the chief scientist at the Cascades Volcano Observatory.
Mount St. Helens is in the Cascade mountain range. He does not think
the volcano will explode for many years. When it does, Moran thinks it
will not be as bad as 1980.
What is Seth Moran's point of view about Mount St. Helens?
(A)
The volcano will never erupt again.
(B)
The volcano will probably not erupt soon.
(C)
If the volcano erupts, many people will be killed.
(D)
If the volcano erupts, it will be worse than the first eruption.