Chapter 5 Study Guide
Answer the following questions in your science notebook.
1. Fill in the table p175-177
Types of stress
Types of Faults
Tension
normal
compression
Reverse fault
shearing
Strike-slip
Sketch the faults
2. Distinguish between the focus and epicenter. p181
Focus is the point below Earth’s surface where rock breaks under stress and causes an
earthquake.
Epicenter is the location on Earth’s surface above the focus.
3. Explain what causes an earthquake. p181
Sudden movement of rock (release of built up stress/friction) along a fault causes an
earthquake.
4. How does the energy of an earthquake travel through Earth? p182
Energy of an earthquake travels through Earth as waves moving away from the focus.
5. Compare and contrast the properties of P waves, S waves, and surface waves. p182183
P waves – first and fastest waves to arrive; compress and expand ground like an
accordion; move through solids and liquids
S waves – secondary waves; vibrate from side to side and up and down; shake ground
back and forth; move through solids only, not liquids
Surface waves – created when P and S waves reach the surface of Earth; slowest
wave; cause severe ground movements; can roll or shake side to side
6. What does each of the following measure? p184-185
Mercalli scale- rates earthquake’s intensity or strength at a given place; describes level
of damage; based on observations at a specific location
Richter scale- rates earthquake’s magnitude by measuring seismic waves; good for
rating small, nearby earthquakes; based on seismograph recordings
Moment Magnitude scale- estimates the total energy released by an earthquake; can
rate all size earthquakes near and far; use seismographs, movement along the fault and
strength of rocks that broke
7. How is the information recorded by a seismograph used? p186-191
Scientists use the difference in arrival times of the P and S waves from 3 recording
stations to triangulate the location of the earthquake epicenter. The amplitude of the
strongest waves can determine the Richter magnitude of the earthquake.
8. What does a seismograph record? p191
A seismograph records the seismic waves produced by an earthquake (the movement
of the ground).
9. Explain what information scientists use to make predictions about earthquakes.
p194-198
Scientists use the location of active faults, the movement of faults, and the history of
past earthquakes in an area to make predictions about future earthquakes.
10. Why can’t scientists predict earthquakes? p194-198
Scientists cannot predict earthquakes because they do not know where along the fault
line the stress will be released or small earthquakes along the fault may relieve some of
the stored energy.
11. What is the cause of most earthquake-related death, damage, and injury? p199-200
Falling objects and flying glass cause the most damage and injury from an earthquake.
12. Explain what to do during an earthquake. p200
Drop, cover, hold
13. How can buildings be designed to minimize the damage during an earthquake?
p201-202
Buildings can be designed to be stronger and more flexible to minimize damage during
an earthquake. Base-isolation reduces the amount of energy that reaches a building
during an earthquake.