green sheet

3. field - The area of magnetic force around a magnet
6. crust - The portion of the earth's crust that primarily contains basalt, is more dense than continental crust, and is about 6 - 7 km thick.
7. - A dark, dense, igneous rock with a fine texture, found in oceanic crust.
11. ridge - An undersea mountain chain where new ocean floor is produced, a divergent plate boundary.
12. spreading - The process that creates new sea floor as plates move away from each other at the mid-ocean ridges.
13. trench - a deep valley along the ocean floor through which oceanic crust slowly sinks towards the mantle in a process known as subduction.
15. - The preserved remains or traces of an organism that lived in the past.
16. plates - Sections of the Earth's crust that move due to convection currents.

1. crust - The portion of the earth's crust that primarily contains granite, is less dense than oceanic crust, and is 20-50 km thick.
2. - A supercontinent containing all of Earth's land that existed about 225 million years ago.
4. drift - The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations.
5. - A usually light-colored igneous rock that is found in continental crust.
8. - The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.
9. of Plate Tectonics - A theory stating that Earth's lithosphere is broken into huge plates that move and change in size over time.
10. Hess - Proposed the theory of seafloor spreading.
14. Wegener - A German scientist who proposed the theory of continental drift.