Science 2.2 Measuring Earthquakes

Question 0

Epicenter

Answer 0

The point on the surface directly above where an earthquake occurs

Question 1

Focus

Answer 1

The point beneath Earth’s surface where rock under stress breaks and triggers an earthquake

Question 2

Surface waves

Answer 2

Slowest seismic waves that produce the most severe ground movements

Question 3

Seismograph

Answer 3

Records ground movements caused by seismic waves as they move through the earth

Question 4

Magnitude

Answer 4

A measurement of earthquake strength

Question 5

What are seismic waves?

Answer 5

Vibrations that travel through Earth carrying the energy released during an earthquake

Question 6

In what order do the three types of seismic waves arrive at a seismograph?

Answer 6

Primary, then secondary and then surface waves (some of the p and s waves turn into surface waves when they reach the surface.

Question 7

Which type of seismic wave produces the most severe ground movement?

Answer 7

Surface waves

Question 8

Describe the moment magnitude scale and explain why it is useful in measuring earthquakes.

Answer 8

A moment magnitude rates the energy by estimating the total energy they release. This is useful because they can tell how strong the earthquake is

Question 9

How do geologists locate the epicenter of an earthquake?

Answer 9

They use the seismograph to plot circles on the map