Plate Motion

3. layer: Earth’s outermost layer of hard, solid rock that is underneath the soil, vegetation,
8. a natural spring that sends hot water and steam suddenly into the air from a hole in the ground
10. or easier to see
14. any of Earth’s main continuous areas of land, such as Africa, Asia, and North America
15. the slow pulling apart of land that is caused by plate movement
18. something we observe to be similar over and over again
20. the outside or top layer of something
21. ash are pushed out on the surface of Earth
26. an extinct reptile that lived about 300 million years ago
27. moving toward the same place
29. an object, diagram, or computer program that helps us understand something by making it

1. evidence of life from the past, such as fossilized bones, footprints, or leaf prints
2. moving apart in different directions
4. how often or fast something happens
5. boundary: the place where two plates meet
6. ridge: an underwater mountain range formed when two plates move apart
7. one of the very large sections of hard, solid rock that make up Earth’s outer layer
9. a sudden shaking of Earth’s surface
11. hot liquid rock below the surface of Earth
12. hot liquid rock on the surface of Earth
13. to examine in detail for a purpose
16. section: a diagram that shows what the inside of something looks like
17. a feature that forms on the surface of a planet, such as a mountain, channel, or sand dune
19. activity: any of the many processes (such as eruptions and lava flows) in which gas, lava,
22. a set of interacting parts forming a complex whole
23. the layer of soft, solid rock underneath Earth’s plates
24. the sudden pushing out of something, such as lava from a volcano
25. a long, deep indentation in the ocean floor formed when two plates move together
28. water