Earthquakes and Seismic Activities

The magnitude of an earthquake measures...

• the amount of energy released.
• the amount of time the earthquake lasted.
• the depth at which the earthquake occurred.
• the temperature of the magma below the epicenter.

S- and P- waves are both types of __________ waves.

• interior
• exterior
• surface
• body

______________ waves cause the most destruction during an earthquake.

• Surface
• P-
• S-
• Body

If a seismograph detects S - waves shortly after it detects P - waves, the earthquake must be...

• very strong.
• very weak.
• close to the seismic station.
• far away from the seismic station.

Many earthquakes happen along the borders of...

• countries.
• tectonic plates.
• climate zones.
• None of the above.

Earthquakes happen every day. Most are too small for humans to notice.

• True
• False
• There is no way of knowing if this statement is true or false!

How much stronger is a magnitude 9.0 earthquake compared to a magnitude 7.0 quake on the Richter Scale?

• twice as big
• 10 times bigger
• 20 times bigger
• 100 times bigger

Which kind of wave arrives second at a seismic station?

• P (primary)
• S (secondary)
• L (love)
• R (Rayleigh)

Which type of body wave usually causes the most damage during an earthquake?

• P wave
• S wave
• Love wave
• Rayleigh

The energy caused by earthquakes travels outward from the focus in the form of...

• electromagnetic waves.
• seismic waves.
• gravity waves.
• chemical energy.