Download Earthquakes

Cage Dix and Marc Hall
2nd period Advanced Earth Science
Mrs. Hirtz
CHAPTER 8 VOCABULARY







Seismology- is the study of earthquakes
Fault- is a break in the earths crust along which blocks of the
crust slide relative to one another due to tectonic plates
Deformation- the change in the shape of rock in response to
stress
Elastic Rebound- the sudden return of elastically deformed
rock to its original shape
Seismic Waves- waves of energy that travel through the earth
P-Waves- the fastest type of seismic waves
S-Waves- the 2nd fastest type of seismic waves
Chapter 8 Vocabulary(Cont.)








Seismograph- a instrument located at or near the surface of the earth
that records seismic waves
Seismogram- a tracing of earthquake motion created by a
seismograph
Epicenter- the point on the earth’s surface directly above an
earthquakes starting point
Focus- the point inside the earth where an earthquake begins
Gap Hypothesis-states that sections at active faults that have had
relatively few earthquakes are likely to have strong earthquakes in the
future
Seismic Gap-an area along a fault where relatively few earthquakes
have occurred
Moho-a place within the earth where the speed of seismic waves
increases sharply
Shadow Zone- an area on the earths surface where no direct seismic
waves from a particular earthquake can be detected
Section 1






Earthquakes take place on tectonic plates.
Numerous features called fault exist in the
Earth’s Crust.
Earthquakes differ in strength and in depth
of where they occur.
Transform motion occurs where two plates
slip past each other.
Convergent motion occurs where two
plates push together.
Divergent motion occurs where two plates
pull away from each other.
Section 1(cont.)
There are two types of seismic waves:
1)P-Waves
2)S-Waves
 P-Waves travel through solids, liquids,
and gases(they are the fastest seismic
waves)
 S-Waves are the second fastest waves.

Section 2
Modified Richter Scale
Magnitude
Estimated Effects
2.0
Can be detected only by seismograph
3.0
Can be felt at the epicenter
4.0
Felt by most in area
5.0
Causes damage at epicenter
6.0
Causes widespread damage
7.0
Causes great, widespread damage
Section 3
The highest earthquake level is in
California.
 Earthquakes that are higher in strength
usually occur less in a period of time.
 People in California are used to
earthquakes now.
 Earthquakes shake the ground out from
under building like a judo master kicks
the feet out from under is opponent.

Section 3(cont.)
They have started to build building and
bridges to with stand earthquakes.
 Put heavier items on lower shelves
incase of an earthquake.
 If you are in school and an earthquake
begins duck under your desk and cover
your head
 Being in an earthquake is a startling
experience.

Section 4
When you put a end of a pencil in water
it looks bent seismic waves do much the
same.
 The first and perhaps most successful
seismic test on another cosmic body
was Earth’s moon.
 Quakes happen everywhere the moon
has a moonquake and even the sun can
have a sun quake.

Work Cited
Earth Science Book
Copyright © 2004 by Holt, Rinehart and
Winston