| A | B |
|---|
| convection | heat transfer by the movement of a heated fluid |
| conduction | heat transfer by direct contact of particles of matter |
| density | a measure of how much mass there is in a volume of a substance |
| Wegener's Hypothesis | the theory that all the continents had once been joined together in a single landmass and have since drifted apart. |
| Pangaea | "all lands" |
| Sonar | SOund NAvigation Ranging |
| Mid-Ocean Ridge | the longest chain of mountains in the world |
| Hess | he proposed the idea that the ocean floors spread, carrying the continents with them. |
| Deep-Ocean Trenches | places where the ocean floor plunges into deep underwater canyons where the oceanic crust bends downward |
| Subduction | the process by which the ocean floor sinks beneath a deep-ocean trench and back into the mantle |
| Three evidences for sea-floor spreading | molten material, magnetic stripes drilling samlpes |
| What drilling samples show about the sea-floor spreading | The farther away from the ridge that samples were taken, the older they were. The youngest samples were always near the center of the ridge |
| The Atlantic Ocean is expanding because of this. | The Atlantic Ocean only has a few short deep-ocean trenches. |
| The Pacific Ocean is not expanding as much as the Atlantic because of this: | The Pacific Ocean has many deep-ocean trenches. |
| The mid-ocean ridge is split by this. | a steep-sided valley |
| The mid-ocean ridge is the longest chain of what in the world? | mountains |
| Continental Drift | the theory that the continents are slowly moving over the earth's surface |
| The theory of the Continental Drift is supported by what three pieces of evidence? | Landforms, fossils and climate |
| fossil | any trace of an ancient organism preserved in rock |
| mass | the amount of matter in an object |
