2. What is an earthquake?
The text describes an earthquake as
something that happens “when two
blocks of earth suddenly slip past
one another.”
A fault is where this happens.
The hypocenter is where the
earthquake begins.
The epicenter is the spot above the
hypocenter.
4. Graphic #1 shows layers of the
Earth.
This diagram shows that the
hypocenter of an earthquake is
below the surface of the Earth.
It also shows that one “block” of
earth might shift higher than
another “block” of earth.
5. What causes earthquakes and
where do they happen?
This section explains that there are four
layers of the Earth, which include the
inner core, the outer core, the mantle,
and the crust.
The surface of the Earth is not just one
large piece—“it is made up of many
pieces like a puzzle.”
The puzzle pieces are tectonic plates.
Sometimes, plates get stuck. When they
become “unstuck,” there is an
earthquake.
7. Graphic #2 shows the four layers of the
Earth.
This diagram helps the reader understand
that these layers are not all the same
size.
It also shows the distance in km of each
layer.
The lithosphere is the smallest layer.
The core, including the inner core and
outer core, is larger than the mantle.
8. Why does the earth shake when
there is an earthquake?
When the edges of two faults are stuck,
energy is stored up.
When the two faults move, the stored
energy comes out in waves.
These seismic waves come “outward from
the fault in all directions.” The text says
these waves are “like ripples on a pond.”
Then, these waves are what shake the
Earth during an earthquake.
10. Graphic #3 shows the different
plates on the Earth.
This map helps the reader
understand that some of the plates
are larger than continents.
Also, some of the plates have more
than one continent on them.
It also shows that the oceans are on
top of the plates.
11. What I would add:
I would add photographs of what it
looks like when an earthquake
happens.
I would even add photos of how
earthquakes affect buildings and
people’s homes.
12. Source: “The Science of Earthquakes.” US Geological Survey. 27 Oct.
2009. Web. 22 Mar. 2012.