Noteform 2-2: Earthquakes and Seismic Waves (pages 51 – 57)
Name: _____________________________________ Section: _____
1. Every day, worldwide, there are ___________________________ earthquakes.
2. The force of _________________________________ cause earthquakes.
3. Stress__________________________ along a fault until the rock breaks…an
earthquake begins. In seconds, the quake releases lots of stored energy.
4. Most earthquakes begin in the _____________________ within about _____ km
of the Earth’s surface.
5. The _____________________ is the area beneath Earth’s surface where rock that
is under stress breaks, triggering an earthquake.
6. The point on the surface directly above the focus is called the ________________
7. Like a pebble thrown into a pond, an earthquake produces vibrations called
waves. These waves carry energy as they travel outward away from the
__________________________.
8. Write the correct letter: _______ waves (primary waves) compress and expand
the ground like a slinky or an accordion.
9. Write the correct letter: _______ waves (secondary waves) vibrate from side to
side, and shake the ground back and forth, as well as up and down.
10. ____________________ waves move more slowly than the other seismic waves,
but they cause the ground to roll like ocean waves, causing severe damage. They
can also cause buildings to shake from side to side.
11. Which kind of seismic wave cannot travel through liquids: ________________
12. The Mercalli Scale was developed to measure earthquake intensity. How many
rating steps are there on this scale?
( from 1 - ______ )
13. Earthquake magnitude is measured using the _______________________ scale.
14. Seismic waves are measured using an instrument called a: ___________________
15. The Moment Magnitude Scale is used by geologists to rate the total
__________________ released by an earthquake.
16. Read the “Lab Zone-Skills Activity” on the bottom of page 55. Classify the
earthquake damage at the locations mentioned using the Mercalli Scale as shown
in Figure 9 at the top of page 55.
A) Mercalli Scale rating = _______________ if many buildings are destroyed; cracks
form in the ground.
B) Mercalli Scale rating = _______________ if several old brick buildings and a
bridge collapse.
C) Mercalli Scale rating = _______________ if canned goods fall off shelves; walls
crack; people go outside to see what’s happening.
17. An earthquake’s magnitude tells geologists how much energy was released by the
earthquake. Each one-point increase in magnitude represents the release of
roughly _______________ times more energy.
18. People scarcely notice earthquakes with magnitudes below ___________.
19. Earthquakes with magnitudes below ______ cause little damage.
20. Earthquakes with a magnitude between _____ and _____ can cause moderate
damage.
21. Earthquakes with a magnitude above _____ can cause great damage.
22. Fortunately, earthquakes with a magnitude above _____ are rare.
23. The farther away the earthquake is from where you are, the ________________
the time between arrival of the P waves and the S waves.
24. Geologists draw at least three circles using data from different seismographs set
up at stations all around the world. The center of the circle represents:
___________________________________
25. The point where the three circles intersect is the location of the ________________
EXTRA: Challenge yourself. Do the “Math-Analyzing Data” on the bottom of page 56.
Question #1: ___________________________________________________
Question #2: ___________________________________________________
Question #3: ____________________________________________________
Question #4: ___________________________________________________