Chapter 8 Earthquakes and Earh's Interior

1. a fracture in Earth along which movement has occurred
3. the point within Earth where an earthquake originates
5. wave a seismic wave that travels along the surface of Earth
7. a small earthquake that follows the main earthquake
9. sometimes associated with earthquakes, in which soils and other unconsolidated materials saturated with water are turned into a liquid that is not able to support buildings.
11. wave earthquake wave that pushes and pulls rocks in the direction of the wave
12. an instrument that records earthquake waves
14. core the solid innermost layer of Earth, about 122 0 kilometers in radius
15. the record made by a seismograph
17. the rigid outer layer of Earth, including the crust and upper mantle
20. wave a seismic wave that shakes particles perpendicular to the direction the wave is traveling
21. the 2890-kilometer-thick layer of Earth located below the crust

2. the Japanese word for a seismic sea wave
3. a small earthquake that often precedes a major earthquake
4. the thin, rocky outer lay of Earth
6. the vibration of Earth produced by the rapid release of energy
7. a weak plastic layer of the mantle situated below the lithosphere;
8. rebound hypothesis the explanation stating that when rocks are deformed, they break, releasing the stored energy that results in the vibrations of an earthquake
10. the location on Earth’s surface directly above the focus, or origin, of an earthquake
13. the boundary separating the crust from the mantle, discernible by an increase in the velocity of seismic waves.
16. magnitude a more precise measure of earthquake magnitude than the Richter scale
18. gap an area along a fault where there has not been any earthquake activity for a long period of time
19. core a layer beneath the mantle about 2260 kilometers thick; contains liquid iron and generates Earth’s magnetic field