Science Ch. 6 Keyterms

4. The record of an earthquake’s seismic waves produced by a seismograph.
6. The force that opposes the motion of one surface as it moves across another surface.
8. The measurement of an earthquake’s strength based on seismic waves and movement along faults.
12. A force that acts on rock to change its shape or volume.
13. A device that records ground movements caused by seismic waves as they move through Earth.
14. The point on Earth’s surface directly above an earthquake’s focus.
16. A scale that rates earthquakes by estimating the total energy released by an earthquake.
17. An earthquake that occurs after a larger earthquake in the same area.
19. A type of fault in which rocks on either side move past each other sideways with little up or down motion.
21. The process by which an earthquake’s violent movement suddenly turns loose soil into liquid mud.
25. An upward fold in rock formed by compression of Earth’s crust.
26. A type of seismic wave that forms when P waves and S waves reach Earth’s surface.
27. A downward fold in rock formed by compression in Earth’s crust.
28. The shaking that results from the movement of rock beneath Earth’s surface.

1. The point beneath Earth’s surface where rock breaks under stress and causes an earthquake.
2. A building mounted on bearings designed to absorb the energy of an earthquake.
3. Stress that stretches rock so that it becomes thinner in the middle.
5. A scale that rates earthquakes according to their intensity and how much damage they cause at a particular place.
7. Stress that squeezes rock until it folds or breaks.
9. A type of fault where the hanging wall slides upward; caused by compression in the crust.
10. The block of rock that forms the upper half of a fault.
11. A type of seismic wave that compresses and expands the ground.
15. The block of rock that forms the lower half of a fault.
18. A type of seismic wave that moves the ground up and down or side to side.
20. A scale that rates an earthquake’s magnitude based on the size of its seismic waves.
22. A type of fault where the hanging wall slides downward; caused by tension in the crust.
23. Stress that pushes masses of rock in opposite directions, in a sideways movement.
24. A large wave produced by an earthquake on the ocean floor.