EARTHQUAKES

4. Scientists who study earthquakes
7. A seismic wave that causes particles of rock to move in a side-to-side direction
9. Study of earthquakes
12. Two forces of plate tectonics that can cause the deformation of rocks
13. A break in the Earth's crust along which blocks of crust slide relative with one another
14. Two lithosphere plates colliding forming a boundary
15. Seismic waves that travel along the Earth's surface
16. Rock deformation that's like a piece of molded clay and doesn't lead to earthquakes
19. Waves that travel through solids, liquids, and gases
20. The change in a rock's shape in response to stress

1. Seismic waves that travel through the Earth's interior
2. The boundary between tectonic plates that are sliding past each other horizontally
3. Giant pieces of Earth's think, outermost layer
5. The boundary between two tectonic plates that are moving away from each other
6. The sudden return of elastically deformed rock to its original shape
8. Rock deformation that's like a stretched rubber band and leads to earthquakes
10. The two types of vertical movement in the Earth's crust
11. A set of deep cracks that form between two tectonic plates pulling away from each other
17. Waves of energy that travel through the Earth
18. Occurs when rock layers bend because of stress