Choice Board Assignment Crossword Puzzle

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Across
  1. 1. the top and thinnest layer of the Earth
  2. 5. formation of new seafloor when magma comes up at mid-ocean ridge
  3. 7. the only liquid layer of the Earth that contains iron and nickel
  4. 8. lowland region formed by a divergent boundary
  5. 11. plates of the Earth's surface that that constantly move
  6. 16. the layer right beneath the lithosphere
  7. 17. are formed at divergent boundaries and mainly at mid ocean ridge
  8. 18. plates that flow independently over the mantle
  9. 20. 2 plates that move towards each other
Down
  1. 2. when the dense plate sinks into the mantle
  2. 3. the center of the Earth that is as hot as the Sun
  3. 4. theory that continents slowly move across the Earth's surface
  4. 6. the scientist who came up with the theory of continental drift
  5. 9. 2 plates that slide past each other
  6. 10. 2 plates that move away from each other
  7. 12. a supercontinent that existed about 250 million years ago
  8. 13. molten material above the surface of the Earth
  9. 14. the mostly-solid bulk of Earth's interior
  10. 15. the rigid outer part of the Earth that consists of the crust and upper mantle
  11. 19. molten material below the surface of the Earth