Download Discovering the mysteries of earthquakes

Discovering the mysteries of
earthquakes
By Milwaukee Journal Sentinel, adapted by Newsela staff on 08.19.14
Word Count 674
Scientists on board the ship Chikyu study samples of rock brought up from a hole drilled deep below the ocean floor near
the Nankai fault off the coast of southern Japan. Photo: Photo courtesy Harold Tobin/MCT
MILWAUKEE — Scientists are drilling deep into the Earth to understand earthquakes.
It is a daring plan.
The Earth's surface is made up of huge plates of rock. Earthquakes erupt when the rocky
plates bang against each other. These happen at what are called faults.
Scientists from the University of Wisconsin-Madison are taking samples of rock from faults
in Japan and New Zealand. They are also measuring the conditions down deep in the
Earth. If the scientists are lucky, they will catch an earthquake in action.
“These are the natural disasters that kill the most people on the planet. So we need to
know as well as we can how they work," said Harold Tobin. He is a geologist at the
University of W-M. Geologists study rocks and how the Earth was formed.
Discovering The Mystery
Earthquakes are some of the worst natural disasters on the planet. Scientists also rarely
know when they are going to happen. Scientists can say how likely it is an earthquake will
happen. But they cannot predict exactly when one will strike. People need early warning of
earthquakes because they have only moments to take cover.
Part of the problem is that scientists don't really know how earthquakes start, and it's hard
to find out. Earthquakes begin miles below the surface of the Earth. People can't go that
far down.
Until now, scientists studied earthquakes by measuring seismic waves. Seismic waves are
waves of energy. They are caused when the plates bump against each other. This
information is useful. But it is like trying to figure out what’s inside your birthday present by
shaking the box. You would know more if you could unwrap it and look inside.
This is why the scientists want to drill down to where earthquakes begin. The drills will
bring up samples of rock to study. Scientists will also measure the conditions deep below
the Earth's surface. These conditions include pressure and temperature. Clifford Thurber is
a geologist at the university. Drilling down deep is one of the few ways of directly
measuring what is going on, he said.
The Dangers Of The Faults
The scientists are drilling at dangerous faults in New Zealand and Japan. These faults
could cause huge earthquakes at any moment.
The project in New Zealand is called the Deep Fault Drilling Project. Thurber and Tobin are
part of a group of scientists studying the Alpine Fault there.
The New Zealand fault has been quiet since 1717. It causes a major quake every 300 or
400 years. Scientists think the area is due for an earthquake soon. Beginning in October,
the geologists will drill nearly a mile deep.
Drilling such deep holes, however, is not easy. This is especially true for faults that are
under water. Many of the most dangerous faults are beneath the ocean.
Tobin spent seven weeks at sea last winter on a scientific drilling ship. Its name is the
Chikyu. On the ship, they braved harsh winds and waves as high as 30 feet. The scientists
drilled into the Nankai Fault. The fault is located off the coast of southern Japan.
The scientists tested the samples of rock that came out of the hole. So far, the scientists
have drilled a mile and a half below the seabed. They plan to drill three miles down.
The measuring tools will remain in the holes collecting information for many years. They will
wait for an earthquake. A quake could strike at any time.
Important New Information
The university researchers also took part in an earlier experiment at the San Andreas fault
in California. The San Andreas fault has caused many earthquakes.
The scientists discovered important information. But, they had many problems. Drilling was
expensive. Also, the measuring tools broke quickly. The temperatures were too high that
deep down.
Scientists learned important lessons from that. Now, in Japan and New Zealand, they will
not drill down to where the worst quakes begin. Instead, they will drill closer to the surface.
These rocks are like the ones down deep, Thurber said.
Quiz
1
Select the paragraph from the section "Discovering The Mystery" that explains how scientists
have predicted earthquakes in the past.
2
Which sentence from the section "The Dangers Of The Faults" describes the challenges
scientists face while drilling at faults?
3
4
(A)
Drilling such deep holes, however, is not easy.
(B)
These faults could cause huge earthquakes at any moment.
(C)
On the ship, they braved harsh winds and waves as high as 30 feet.
(D)
Many of the most dangerous faults are beneath the ocean.
What is the main idea of the article?
(A)
Scientists are drilling at some of the world's most dangerous faults to be
able to better understand and predict earthquakes.
(B)
Scientists don't really know how earthquakes start and it is very difficult to
find out that information.
(C)
Scientists tested samples of rock that came out of the holes they drilled in
New Zealand and Japan.
(D)
Scientists learned important lessons from drilling holes at the San Andreas
fault that will help them now.
Which sentence from the article is MOST relevant to the main idea of the article?
(A)
Geologists study rocks and how the Earth was formed.
(B)
The project in New Zealand is called the Deep Fault Drilling Project.
(C)
Tobin spent seven weeks at sea last winter on a scientific drilling ship.
(D)
Scientists from the University of Wisconsin-Madison are taking samples of
rock from faults in Japan and New Zealand.
Answer Key
1
Select the paragraph from the section "Discovering The Mystery" that explains how scientists
have predicted earthquakes in the past.
Paragraph 7:
Until now, scientists studied earthquakes by measuring seismic waves. Seismic
waves are waves of energy. They are caused when the plates bump against each
other. This information is useful. But it is like trying to figure out what’s inside
your birthday present by shaking the box. You would know more if you could
unwrap it and look inside.
2
3
4
Which sentence from the section "The Dangers Of The Faults" describes the challenges
scientists face while drilling at faults?
(A)
Drilling such deep holes, however, is not easy.
(B)
These faults could cause huge earthquakes at any moment.
(C)
On the ship, they braved harsh winds and waves as high as 30 feet.
(D)
Many of the most dangerous faults are beneath the ocean.
What is the main idea of the article?
(A)
Scientists are drilling at some of the world's most dangerous faults to
be able to better understand and predict earthquakes.
(B)
Scientists don't really know how earthquakes start and it is very difficult to
find out that information.
(C)
Scientists tested samples of rock that came out of the holes they drilled in
New Zealand and Japan.
(D)
Scientists learned important lessons from drilling holes at the San Andreas
fault that will help them now.
Which sentence from the article is MOST relevant to the main idea of the article?
(A)
Geologists study rocks and how the Earth was formed.
(B)
The project in New Zealand is called the Deep Fault Drilling Project.
(C)
Tobin spent seven weeks at sea last winter on a scientific drilling ship.
(D)
Scientists from the University of Wisconsin-Madison are taking samples
of rock from faults in Japan and New Zealand.