| A | B |
|---|
| Geology | Study of earth's physical structure and history |
| Crust | Solid, rocky, surface layer of earth |
| % of water on earth | More than 70% |
| island | body of land completely surrounded by water |
| isthmus | Narrow strip of land w/water of each side, joining two larger bodies of land |
| delta | A flat low-lying plain that is sometimes formed at the mouth of a river |
| lake | A body of fresh or salt water of considerable size surrounded by land |
| magma | Molten rock inside the earth |
| faults | A fracture, or break, in the earth's crust |
| Continental Drift Theory | Idea that continents slowly shift their positions due to movement of the tectonic plates on which they ride |
| Convection | A circular movement caused when a material is heated, expands and rises, then cools and falls |
| Converging (2 types) | When two continental plates meet they form mountains. When both are oceanic plates, they form islands |
| core | Earth's center, consisting of very hot metal that is dense and solid in the inner core and molten or liquid in the outer core |
| continents | The seven large landmasses of the earth's surface, Africa, Asia, North America, South America, Antarctica, Australia, Europe |
| 4 major types of landforms | Mountains, Hills, Plateaus, Plains |
| archipelago | A group of islands |
| peninsula | A strip of land that juts out into an ocean |
| gulf | Portion of ocean or sea partly enclosed by land |
| butte | An isolated hill or mountain rising abruptly above the surrounding land |
| lava | Magma, or molten rock from earth's mantle, that breaks through the surface of the earth during volcanic activity |
| plate tectonics | Theory that earth's outer shell is composed of a number of large, unanchored plates, or slabs of rock, whose constant movement explains earthquakes and volcanic activity |
| Sea Floor Spreading | The study of the ocean floor |
| spreading | When plates pull away from one another |
| faulting | When there is a break in the earth's crust. Movement could go sideways, up or down |
| mantle | Surrounds the core, and is a thick layer of rock that has pockets of magma |
| relief | The difference in elevation between the highest and the lowest points |
| strait | Narrow passage of water connecting two large bodies of water |
| volcano | Form when molten rock breaks through earth's crust |
| sound | To measure or try the depth of water |
| canyon | A deep valley with steep sides, often with a stream flowing through it |
| volcanism | Involves the movement of magma inside the earth |
| fold | When rock layers bend an buckle |
| Pangea | The hypothetical landmass that existed when all continents were joined |
| Rift Valley | A large split along the crest of an underwater mountain system where small earthquakes and volcanic eruptions frequently occur |
| subduction | When a oceanic plate meets a continental plate, it slides under the lighter plate and down into the mantle. The oceanic rock then melts deep in the earth |
| Ring of Fire | A ring of volcanic mountains surrounding the rim of the Pacific Ocean |
