| A | B |
|---|
| lithosphere | "sphere of rock" |
| asthenosphere | "weak sphere" |
| convection current | driving force of plate tectonics |
| plate tectonics | study of the formation and motions of pieces of lithosphere |
| magnetic reversal | event that is due to happen to earth soon |
| spreading center | a rift valley is located in this |
| divergent | boundary where plates move apart |
| convergent | boundary where plates move together |
| subduction zone | area where one plate moves under another |
| sliding boundary | when one plate slides past another |
| reverse polarity | opposite of the type of magnetism earth has now |
| craton | ancient continental core |
| Canadian Shield | exposed portion of the North American craton |
| trench | a feature common at subduction boundaries |
| thin-skinned thrusting | pushing of this horizontal sheets of crust |
| terrane | "moved" chunk of lithosphere |
| continental drift | theory that the continents where moving |
| slab pull | when the edge of a plate sinks in a subduction zone and pulls the rest of the plate with it |
| ridge push | when a plate is pushed up at a rift zone and slides down along the lithosphere-asthenosphere boundary |
| collision boundary | convergent boundary between two continental plates |
| fossil link | use of prehistoric animals' remains to prove continental drift |
| Mid-Atlantic ridge | surrounds a long rift valley in the middle of the Atlantic Ocean |
| tektonikos | means "of a builder |
| Pangaea | ancient supecontinent |
| Great Rift Valley | famous spreading center in Africa |
| Global Positioning System | technology used to track the movements of plates |
| East Pacific Rise | mid-ocean ridge that separates the Nazca and S.A. plates |
