| A | B |
|---|
| CRUST | The layer of rock that forms Earth's outer surface. |
| MANTLE | The layer of hot, solid material between Earth's crust and core. Thickest layer. |
| OUTER CORE | A layer of molten iron and nickel that surrounds the inner core of Earth. |
| CONVECTION CURRENT | A motion that transfers heat energy in a material. |
| PANGAEA | The name of the single "supercontinent" that broke apart 225 million years ago and gave rise to today's continents. |
| CONTINENTAL DRIFT | The hypothesis that the continents slowly move across Earth's surface. |
| FOSSIL | The preserved remains or traces of living things. |
| MID-OCEAN RIDGE | The undersea mountain chain where new ocean floor is produced; a divergent plate boundary. |
| DEEP-OCEAN TRENCH | A deep valley along the ocean floor through which oceanic crust slowly sinks toward the mantle. |
| SUBDUCTION | The process by which oceanic crust sinks beneath another plate at a convergent boundary. |
| PLATE | A section of the lithosphere that slowly moves over the asthenosphere, carrying pieces of continental and oceanic crust. |
| PLATE TECTONICS | The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle. |
| FAULT | A break or crack in Earth's lithosphere along which the rocks move. |
| TRANSFORM BOUNDARY | A plate boundary where two plates move/scrape past each other in opposite direction. |
| DIVERGENT BOUNDARY | A plate boundary where two plates move away from each other. Divide |
| RIFT VALLEY | A deep valley that forms where two plates move apart. |
| CONVERGENT BOUNDARY | A plate boundary where two plates push toward each other. |
| 3 Rock Types | igneous: formed from magma or lava; sedimentary: forms when particles from other rocks or plant/animal remains are pressed and cemented together; metamorphic: rock that has been changed into a different type under the influence of heat or pressure |
| Trace Fossil | A type of fossil that provides evidence of the activity of ancient organisms |
| Evolution | Process by which all the different kinds of living things have changed over time |
| Law of Superposition | The geologic principle that states: In undisturbed horizontal layers of sedimentary rock, each layer is older than the layer above it and younger than the layer below it. |
| Intrusion | An igneous rock layer formed when magma "intrudes" into other rock layers and hardens beneath Earth's surface |
| Inner Core | Ball of hot, solid metals inside Earth's center |
| Lithosphere | Earth's crust and very top of the mantle together |
| Asthenosphere | A layer of hotter, softer rock in the upper mantle that flows slowly and allows plates to move. |
