1. Cage Dix and Marc Hall 2 nd period Advanced Earth Science Mrs. Hirtz

2.  Seismology- is the study of earthquakes  Fault- is a break in the earths crust along which blocks of the crust slide relative to one another due to tectonic plates  Deformation- the change in the shape of rock in response to stress  Elastic Rebound- the sudden return of elastically deformed rock to its original shape  Seismic Waves- waves of energy that travel through the earth  P-Waves- the fastest type of seismic waves  S-Waves- the 2 nd fastest type of seismic waves

3. Chapter 8 Vocabulary(Cont.)  Seismograph- a instrument located at or near the surface of the earth that records seismic waves  Seismogram- a tracing of earthquake motion created by a seismograph  Epicenter- the point on the earth’s surface directly above an earthquakes starting point  Focus- the point inside the earth where an earthquake begins  Gap Hypothesis-states that sections at active faults that have had relatively few earthquakes are likely to have strong earthquakes in the future  Seismic Gap-an area along a fault where relatively few earthquakes have occurred  Moho-a place within the earth where the speed of seismic waves increases sharply  Shadow Zone- an area on the earths surface where no direct seismic waves from a particular earthquake can be detected

4. Section 1  Earthquakes take place on tectonic plates.  Numerous features called fault exist in the Earth’s Crust.  Earthquakes differ in strength and in depth of where they occur.  Transform motion occurs where two plates slip past each other.  Convergent motion occurs where two plates push together.  Divergent motion occurs where two plates pull away from each other.

5. Section 1(cont.)  There are two types of seismic waves: 1)P-Waves 2)S-Waves  P-Waves travel through solids, liquids, and gases(they are the fastest seismic waves)  S-Waves are the second fastest waves.

6. Section 2 Modified Richter Scale MagnitudeEstimated Effects 2.0Can be detected only by seismograph 3.0Can be felt at the epicenter 4.0Felt by most in area 5.0Causes damage at epicenter 6.0Causes widespread damage 7.0Causes great, widespread damage

7. Section 3  The highest earthquake level is in California.  Earthquakes that are higher in strength usually occur less in a period of time.  People in California are used to earthquakes now.  Earthquakes shake the ground out from under building like a judo master kicks the feet out from under is opponent.

8. Section 3(cont.)  They have started to build building and bridges to with stand earthquakes.  Put heavier items on lower shelves incase of an earthquake.  If you are in school and an earthquake begins duck under your desk and cover your head  Being in an earthquake is a startling experience.

9. Section 4  When you put a end of a pencil in water it looks bent seismic waves do much the same.  The first and perhaps most successful seismic test on another cosmic body was Earth’s moon.  Quakes happen everywhere the moon has a moonquake and even the sun can have a sun quake.

10. Work Cited Earth Science Book Copyright © 2004 by Holt, Rinehart and Winston