Plate tectonics

2. boundaries The boundary of plate, there are three types
4. current currents in earth's mantle and is the cause of plate tectonics
6. floor spreading Hess's theory that new sea floor forms when magma is forced up by plates moving apart
7. Plastic like layer of the earth than the lithospheric plates float on
9. Hess Sea Floor spreading was his theory
11. The point after a surface rock reaches its elastic limit and brake
13. Drift Wegener's theory that all the continents were once we a part of a supercontinent
15. The second layer of the earth, made of lava
16. boundary The boundary of plates that are moving away, and then cause lava to flow through the new crack in the earths crust (also know as a constructive boundary)

1. Layer of earth's crust that is about 100 km thick, made of the crust and the upper mantle
3. boundary The boundary of plates that slide by each other, and causes earthquakes.
5. One of two supercontinent that separated from pangaea
7. Wegener Continental drift was his theory
8. valley A valley between highlands caused by a fault
10. A supercontinent that was made of all the continents
12. ridge A underwater mountain range that the plates are moving apart and new land is being made
13. boundary The boundary of plates that collide (also know as a destructive boundary)
14. Time Scale A way to date rock by looking at little bits of iron in the rock and use that and the fact that the earth magnetic field has shifted