Unit 3 Lesson 1

4. Evidence that Earth's interior contains liquid and solid layers
5. The force responsible for pulling all matter together
7. 4.6 billion years ago, a cloud of gas and dust began to pull together and rotate
9. A source of heat within the Earth
11. Seismic waves travel ______ through rigid, dense rock
12. These waves move rock side-to-side and can only travel through solids
15. This layer is a liquid due to very high temperatures
16. The outermost physical property layer. This layer is in a solid state
18. A semi-solid physical property layer of the mantle below the lithosphere

1. The force of gravity pulled more dense materials towards Earth's core and less dense materials towards the crust
2. These waves squeeze rock in the same direction the wave is traveling. They can travel through solids, liquids, and gases
3. A solid physical property layer beneath the asthenosphere
6. This layer is under immense pressure and is a solid
8. Scientists collect and record seismic-wave data with these devices
10. The outermost compositional layer of the Earth
13. Waves of energy that travel through rock due to earthquakes
14. The compositional layer beneath the crust
17. The compositional layer that makes up the center of the Earth