Earthquakes

4. the measure of the energy released by an earthquake
5. instrument used to record the seismic waves generated by earthquakes
6. a tracing of earthquake motion
10. vibrations that cause different types of ground motion
11. point on Earth's surface directly above an earthquake's starting point
14. a series of extremely long waves that can travel across the ocean at speeds of up to 800 km/h
15. ground movements that occur when blocks of rock in Earth move suddenly and release energy
16. known as p waves, or primary waves, these are the fastest body waves
17. a break in Earth's crust along which blocks of rock move
18. the effects of an earthquake and how the earthquake is felt by people
21. seismic waves that travel through Earth's interior
22. the return of rock to its original shape after elastic deformation

1. the process by which rock changes shape due to stress
2. the process when water-saturated soil or sediment particles are shaken by seismic waves and become completely surrounded by water
3. known as s waves, or secondary waves, these waves cannot travel through liquid parts of Earth
7. the name of the scale used to measure the intensity of an earthquake
8. a place within Earth along a fault at which the first motion of an earthquake occurs
9. where two or more tectonic plates meet
12. the name of the scale used to measure the magnitude of an earthquake
13. seismic waves that travel along the surface of Earth rather than through it
19. a weight placed in a building used to counteract the building's movements when an earthquake causes it to shake
20. the difference between the arrival times of P waves and S waves