Download Seismic Waves Activity

Seismic Waves/Earthquake Notes
Review:
Scientists study and record ____________________ data and ___________________ activity in
order to support the theory of plate tectonics. The evidence proves that there is a distinct relationship
between seismic activity, volcanic activity, and the lithospheric plate boundaries.
Seismic Data and Plate Tectonics: The interaction along ___________ boundaries results in an increased
frequency (occurrence) of earthquakes at those locations. Additionally, stronger earthquakes are more
likely to occur along active plate boundaries. Strong earthquakes are more common
at___________________ and ______________________ plate boundaries. The San Andreas fault in
California is an example of an active transform plate boundary.
How are earthquakes measured? Earthquakes are measured using the ____________________________. The
strongest earthquake ever measured was a 9.5 on the Richter Scale. This is a measurement of the
amount of energy released from the earthquake. The _Richter Scale expresses or measures the magnitude
(energy) of an Earthquake and measures the energy released. The scale goes from 1 to 10 .
Seismic Waves Activity: Illustrate & explain the seismic waves based on the Pop & Lock
Activity.
Primary (P) Waves
Secondary (S) Waves
Surface Waves
Seismic Waves (3 types)
_______________________________ are waves generated by an earthquake that travel through the Earth.
These waves can cause the ground to move forward, backward, up, down, and even to ripple. Seismic
Waves are generated at the ____________________ time but move in different ways, and at different speeds.
There are 3 types of Seismic Waves:
 ____________________________________________
 _____________________________________________
 ______________________________________________
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Type of Wave/
Illustration
PRIMARY
WAVES:
P WAVES
Position
The _______________
seismic wave to move out
from the earthquake focus,
the point where the energy is
released
Travel the _____________
of the three waves
SECONDARY
WAVES:
S WAVES
The ________________
wave to Move out from the
earthquake focus
Move _______________
than primary waves
Movement
Moves through what
states of matter
___________ and ______________ Moves through
rock creating a back-and-forth
_______________
motion in the direction the wave is
and ______________
moving…. This known as a
layers of Earth (it
(___________________________
also can move in
gas)
wave)
A type of seismic wave that
compresses and expands the
ground
Move at __________________ to
primary waves causing rocks to
move up and down and side to
side…this is known as a
(_____________________ wave)
A type of seismic wave that moves
the ground up and down or side
to side
Can only move
through
_______________
rock
If S-waves can only
move through solids,
then which EARTH
layer can’t it go
through?
shear waves - move material
perpendicular to wave movement
SURFACE
WAVES
Form when _______ and
_________ waves reach the
______________ AND
THESE WAVES ARE
CONSIDERED THE
____________________
SEISMIC WAVES.
Especially damaging to
buildings
Can cause the ground to shake
making rock sway from side to
side and roll like an ocean wave
Travel just below or along the
ground’s surface
Moves
through_________
the states of matter:
solid, liquid, and gas
Produces motion in the upper crust
Motion can be up and down
Motion can be around
Motion can be back and forth
Mainly moves like P & S waves
Scientists use the principle that the _______________ and _________________ of a seismic wave depends on the
material it travels through. Because of the behavior of these different waves, scientists have indirect evidence for the
solid inner core and liquid outer core of Earth; because earthquake waves travel faster through the
___________________ than through the crust, scientists know that the mantle is denser than the crust.
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MEASURING EARTHQUAKES
The energy spreads outward in all directions as vibrations called ________________________. Seismic
waves can be measured and recorded by a ____________________________.
______________________________ are instruments or a device that detects and records seismic or
earthquake waves. It measures the vertical ground motion and the horizontal ground motions (N-S/EW). It also traces wave shapes onto paper and translates waves into an electronic signal.
The vibration record, called a ___________________________, looks like jagged lines on paper. Seismograms
are traces of amplified, electronically recorded ground motion made by seismographs.
Measuring the time between the arrival of the P and S waves determines the _________________ between the
recording seismograph and the earthquake epicenter.
SEISMOGRAPH
SEISMOGRAM
LOCATING AN EARTHQUAKES EPICENTER
______________________________ identifies the epicenter of an earthquake.
The location of an earthquake’s epicenter is found by plotting ___________
circles on a map from the records of three seismograph stations and finding the
point where the three circles _______________________ Three seismograph
Triangulation
stations are needed to locate the epicenter of an earthquake. Triangulate means to use three positions to determine
an exact location.
How do scientists calculate how far a location is from the epicenter of
an earthquake? CALCULATING THE S-P INTERVAL:
- Scientists calculate the difference between arrival times of the P waves and S waves
- The further away an earthquake is, the greater the time between the arrival of the P waves and the S waves
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