Earthquakes and Volcanoes

3. The ______ thickest layer of the Earth and consists of two layers which are the lithosphere and asthenosphere.
5. A rigid layer made up of the uppermost part of the mantle and part of the crust.
6. A deep valley where two plates move apart.
7. A break or crack in the Earth's lithosphere in which rocks move.
10. __________________ cause the plates on the Earth's surface to move.
12. Alfred Wegener's theory that all the continents used to be one landmass, and have broken apart since then.
14. A plate boundary where two plates move towards each other.
15. Theory that the plates on the Earth's surface are in motion, and driven by convection currents.

1. An undersea mountain chain where new ocean floor is produced, and it is a divergent plate boundary.
2. ______ is a huge landmass that broke apart around 225 million years ago.
4. A plate boundary where two plates move away from one another.
8. The layer of rock that is the Earth's surface.
9. A deep canyon located on the ocean floor.
11. A layer consisting of molten iron and nickel that covers the inner core.
13. A huge, dense ball of solid material located in the center of the Earth.