Volcanoes, Earthquakes, and Plate Tectonics Review

The point beneath earth's surface where rock breaks under stress and triggers an earthquake is called the

• syncline
• footwall
• epicenter
• focus

The type of seismic waves that arrive at the surface first and move by compressing and expanding the ground like an accordion are called

• S waves
• P waves
• surface waves
• Mercalli waves

S waves are also called

• primary waves
• secondary waves
• surface waves
• focus waves

Compared to P waves and S waves, surface waves move

• faster
• slower
• at the same rate
• farther from the epicenter

In what direction do seismic waves carry the energy of an earthquake?

• away from focus
• toward the focus 
• from the surface to the interior
• through the mantle only

The rating system that estimates the total energy released by an earthquake is called the 

• Richter scale
• moment magnitude scale
• mechanical seismograph scale
• Mercalli scale

What does a seismograph record?

• the Mercalli scale rating from an earthquake
• the speed of seismic waves
• the ground movements caused by seismic waves
• the location of the epicenter

If the Coast Guard warns of a giant wave of water approaching the shore as a result of a major earthquake, they are warning of

• an aftershock
• liquefication
• a tsunami
• landslides

What is the minimum number of seismograph stations required in order to determine the exact location of an earthquake's epicenter?

• 1
• 2
• 3
• 4

What happens to a tsunami as it approaches shallow water?

• It causes liquefaction.
• I causes large earthquakes.
• Its wave height decreases.
• Its wave height grows.