Plate Tectonics
Across
- 3. Convection currents in the mantle produce a force that causes motion called _____.
- 4. As a slab sink, it pulls on the rest of the plate with a force called _____.
- 9. The theory of ____ drift suggested that continents are in constant motion on the surface of Earth.
- 12. The layer that is so hot that it behaves like plastic material.
- 15. Continents fit like pieces of a..
- 19. The plate tectonics move several ____ each year.
- 21. Wegener needed more scientific _____ to support his theory.
- 22. A state in which magnetized objects will orient themselves to point north is called ____ polarity.
- 23. A _____ plate boundary forms where two plates collide.
- 25. Mountain ranges in the middle of the ocean are called ____ ridges.
Down
- 1. The ____ of Plate Tectonics states that Earth's surface is made of rigid slabs of rock that move with respect to each other.
- 2. Denser plate sinks below buoyant plate
- 5. Cold, rigid outermost rock layer
- 6. _____ on seafloor contains iron-rich minerals that are magnetic.
- 7. A _____ plate boundary forms where two plates separate.
- 8. Process by which new oceanic crust forms along a mid-ocean ridge and older oceanic crust moves away from the ridge.
- 10. Depth of the ocean determined by an ____ sounder.
- 11. Rising mantle material at mid-ocean ridges creates the potential for plates to move away from the ridge with a force called ____.
- 13. Wegener could not explain ___ the continents moved.
- 14. A state in which magnetized objects would reverse direction and orient themselves to point south is called ____ polarity.
- 16. _____ crust forms at mid-ocean ridges.
- 17. Supercontinent.
- 18. A _____ plate boundary forms where two plates slide past each other.
- 19. Circulation of material caused by differences in temperature and density
- 20. _____ reversal occurs when the magnetic field reverses direction.
- 24. ____ lava forms when lava cools rapidly since it erupts in water.