| A | B |
|---|
| continental drift | continents have moved slowly to their current locations |
| Alfred Wegener | developed the theory of continental drift |
| mesosaurus | reptile fossil found in South America and Africa |
| glossopteris | fossil plant found in Africa, Australia, and Antarctica |
| fossils of warm-weather plants found on this island | Spitzbergen, in the Arctic Ocean |
| Appalchian Mountains are similar to these rock structures | Mountains in Greenland and Western Europe |
| seafloor spreading | hot, less dense material carries seafloor away from ridge |
| Harry Hess | developed the theory of seafloor spreading |
| Mid-ocean ridges | underwater mountain ranges |
| sound waves | helped to discover mid-ocean ridges |
| This is how mid-ocean ridges are formed | New seafloor cools,contracts, becomes denser, and sinks |
| Found at the mid-ocean ridges | Youngest rocks in the ocean |
| Glomar Challenger had this tool | Drilling rig to obtain rock samples from seafloor |
| Exotic life forms found on seafloor | giant clams, mussels, and tube worms |
| Magnetic reversals are recorded here | Iron-bearing rocks formed in mid-ocean ridges |
| Magnetic time scale | Provided strong support that seafloor spreading was occurring |
| plates | sections of Earth's crust and upper mantle |
| plate tectonics | plates float & move around on the asthenosphere |
| lithosphere | Earth's crust and part of upper mantle |
| asthenosphere | plasticlike layer below lithosphere |
| divergent boundary | plates are moving apart |
| convergent boundary | plates move together |
| subduction | oceanic plate sinks under continental plate |
| transform boundary | plates slide past one another |
| convection current | cycle of heating,rising,cooling,sinking |
| strike-slip fault | rocks on opposite sides of a fault move in opposite directions or same direction but at different rates |
| Satellite Laser Ranging System | measures movement of Earth's plates |
