Across
- 5. most dense layer in three layer model
- 7. separation based on density
- 8. the middle layer int he five layer model
- 9. low density minerals in Earth's crust
- 12. the denser type of crust
- 13. made of solid iron and nickel
- 14. the force that pulls matter towards Earth's center
- 15. the only liquid layer of Earth
Down
- 1. Earth is believed to be about 4.6 _______years old
- 2. outer layer in compositional model of Earth
- 3. outermost physical layer of Earth
- 4. Earth's three layer model is based on _____
- 6. middle layer in three layer model of Earth
- 10. source of heat in Earth
- 11. energy released by an earthquake