Across
- 7. ridge: a plate boundary in the ocean
- 8. plates: 7 large pieces of rock
- 9. A rigid layer of rock
- 11. drift: Alfred Wegener, puzzle piece continents, rock structures, fossils, climate
- 13. made of oxygen, silicon, iron, 5-40 km thick, solid
- 15. core: made of iron and nickel, 1200 km thick, solid
Down
- 1. boundaries: 2 plates moving away from each other
- 2. mass per unit of volume
- 3. The ocean floor sinks beneath the crust
- 4. core: made of iron and nickel, 2250 km thick, liquid
- 5. spot: am area in the mantle that can cause a chain of volcanic islands to form
- 6. made of oxygen, silicon, iron, magnesium, 2900 km thick, solid and plasticity
- 10. super continent, before the continents were separate
- 12. boundaries: 2 plates grind against each other
- 14. Valley: 2 continents moving away from each other