plate tectonics

2. Convective heat transfer, often referred to simply as convection, is the transfer of heat from one place to another by the movement of fluids
4. volcanic activity or phenomena
6. a feature on the Earth's surface that is part of the terrain
7. one of the plates oceanic crust and lithosphere mantle is pushed or subducted under the other it mixes with the overlying mantle and the addition of water to the hot mantle lowers the crusts melting point and leads to the formation of magma
12. a supercontinent that existed during the late Paleozoic and early Mesozoic eras
13. a rigid layer of the earths crust is believed to drift slowly
15. oceanic crust is often forced down into the mantle where it begins to melt
17. the rigid outer part of the earth, consisting of the crust and upper mantle
18. gravitational forces acting on the young, raised oceanic lithosphere around mid-ocean ridges
19. the science that deals with the earth's physical structure and substance, its history, and the processes that act on it

1. a theory that explained how continents shift position on Earth's surface
3. Two plates sliding past each other
5. a German polar researcher, geophysicist and meteorologist. During his lifetime he was primarily known for his achievements in meteorology and as a pioneer of polar research
8. the upper layer of the earth's mantle below the lithosphere in which there is low resistance to plastic flow and convection is thought to occur
9. when two tectonic plates move away from each other
10. large-scale processes affecting the structure of the earth's crust
11. is the movement of the plates that make up earths crust lightest most buoyant rock layer
14. the sideways and downward movement of the edge of a plate of the earth's crust into the mantle beneath another plate
16. the pulling force exerted by a cold, dense oceanic plate plunging into the mantle due to its own weight