| A | B |
|---|
| Geology | The study of the earth's physical structure and history |
| Crust | The solid, rocky, surface layer of the earth |
| % of water on earth | More than 70% |
| Island | a tract of land surrounded by water and smaller than a continent |
| Isthmus | A narrow strip of land having water on each side and joining two larger bodies of land |
| delta | A flat, low-lying plain that is sometimes formed at the mouth of a river-the place where the river enters a lake, a larger river, or an ocean |
| lake | a considerable inland body of standing water |
| magma | molten rock inside the earth |
| faults | Fractures, or breaks, in the earth's crust |
| Continental Drift Theory | The 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 plates of the same type (oceanic or continental) crash into each other |
| core | The 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 | Any of the seven large landmasses of the earth's surface: Africa, Antarctica, Asia, Australia, Europe, North America, and South America |
| 4 major types of landforms | Mountains, hills, plateaus, and plains |
| archipelago | A group of islands |
| peninsula | A strip of land that juts out into an ocean |
| gulf | a part of an ocean or sea extending into the land |
| butte | an isolated hill or mountain with steep or precipitous sides usually having a smaller summit area than a mesa |
| lava | Magma, or molten rock from the earth's mantle, that breaks through the surface of the earth during volcanic activity |
| plate tectonics | The theory that the 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 theory that the crust is being created at oceanic ridges and destroyed at trenches |
| spreading | When plates pull away from each other |
| faulting | When plates slide or grind past each other |
| mantle | A thick layer of mostly solid rock beneath the earth's crust that surrounds the earth's core |
| relief | The differences in elevation, or height, of the landforms in any particular area |
| strait | a comparatively narrow passageway connecting two large bodies of water |
| volcano | a vent in the crust of the earth or another planet from which usually molten or hot rock and steam issue |
| sound | a long broad inlet of the ocean generally parallel to the coast |
| canyon | a deep narrow valley with steep sides and often with a stream flowing through it |
| volcanism | volcanic action or activity |
| fold | A bend or buckle in the earth's crust |
| Pangaea | The belief that there was once a single "supercontinent" |
| Rift Valley | A large aplit along the crest of an underwater mountain system where small earthquakes and volcanic eruptions frequently occur |
| subduction | When an oceanic plate and a continental plate crash into each other |
| Ring of Fire | A circle of volanoes surrounding the Pacific Ocean |
