Chapter 14 Study Guide
Which fault has rock above the fault surface moving upward relative to the rock below the fault surface?
Reverse
What type of force causes a reverse fault?
Compressive
The force that causes rocks on either side of a fault to slide past each other is __________.
Shear
What happens when rocks move over, under, or past each other along fault surfaces?
An earthquake
What type of force causes a normal fault to move?
Tension
What type of fault causes a strike-slip fault?
Shear
What instrument is used to measure earthquakes?
Seismograph
Which waves are responsible for most damage caused by earthquakes?
Surface Waves
When the elastic limit of rocks is passed, they begin the move along surfaces called ___________.
Fault
Which fault has rocks moving past each other with little vertical movement?
Strike-slip
Which fault has rock above the fault surface moving relative to the rock below the fault surface?
Normal
What are the layers of the Earth from the center?
Inner core, outer core, lower mantle, upper mantle, crust
What is the point on Earth’s surface directly above the earthquake focus?
Epicenter
The height of the lines traced on the paper record of a seismograph is a measure of the energy that is released, or the _________, of the earthquake.
Magnitude
Which waves move rock particles in a backward, rolling motion, and a side-to-side, swaying motion?
Surface waves
What moves through the Earth by causing particles in rocks to move at right angles to the direction of wave travel?
Secondary waves
Which layer of the Earth is the largest?
Mantle
What is the inner core made mostly of?
Iron
What is the point inside Earth where an earthquake’s energy first releases?
Focus
What is the boundary between the crust & upper mantle called?
Mohorovicic discontinuity, or Moho
If you are outdoors when an earthquake hits, what should you do?
Stay in the open. Get away from powerlines or anything that might fall on you. Stay away from building, chimneys, or other parts of buildings that could fall on you.
Structures built to resist damage from shaking of earthquakes are known as __________.
Seismic-safe structures
Ocean waves caused by earthquakes are called seismic sea waves, or _______.
Tsunamis
Scientists who study earthquakes & seismic waves are ___________.
Seismologists
Wet soil can be strong most of the time, but the shaking from an earthquake can cause it to act more like a liquid. This is called __________.
Liquefaction
_______ an earthquake, you can make your home as earthquake safe as possible by taking certain steps to prevent damage.
Before
If you are indoors when an earthquake hits, what should you do?
Move away from windows & objects that could fall on you Move away from windows & objects that could fall on you. Seek shelter in a doorway or under a sturdy table or desk.
The Richter scale has no _______________.
Upper limit
What is used to describe the strength of an earthquake & is based on the height of the lines on the seismogram?
Righter magnitude scale
Earthquakes can also be describe by the amount of _____________.
Damage they cause
After an earthquake hits you should,
Check any gas or water lines for damage, and be careful of damaged areas because it could contain broken glass.
What describes the intensity of an earthquake using the amount of structural & geologic damage in a specific location?
Modified Mercalli intensity scale
____________ structures stand up to vibrations that occur during an earthquake.
seismic-safe
Most earthquake damage occurs when surface waves cause what to collapse?
Buildings, bridges, & roads
Scientists record thousands of earthquakes every day with magnitudes of less than ___________.
3.0