| A | B |
|---|
| International Dateline | An imaginary line agreed upon as the place where each new calendar day begins. It runs North and South through the pacific. |
| Arctic Circle | The imaginary boundary of the northern polar region. |
| Antarctic Circle | The imaginary boundary of the southern polar region. |
| physical map | A map that shows the earth's natural features like oceans, continents, mountains and deserts. |
| relief map | A map that shows the differences in elevation. |
| erosion | the movement of weathered materials, including gravel, soil and sand; usually caused by water, wind and glaciers. |
| weathering | the chemical or mechanical process by which rock is gradually broken down, eventually becoming soil. |
| irrigation | The artificial watering of farmland; canals that draw water from rivers. |
| faults | fractures or breaks in the earth's crust. |
| folds | Bends or buckles in the earth's crust. |
| archipelago | A group of islands. |
| bay | A part of the sea or lake which extends into the land. A bay is usually smaller than a gulf. |
| canal | A waterway dug across land for ships or small boats to go through. |
| canyon | A narrow valley with high, steep sides. |
| cape | A point of land extending into the water. |
| continent | Any of the seven large land masses of the earth's surface. A large body of land separated, or nearly separated by a large body of water. |
| delta | The deposit of earth and sand that collects at the mouth of some rivers. |
| desert | A dry barren region that is usually sandy and without trees. |
| foothills | Low hills at the base of a mountain or mountain range. |
| political map | A map that shows political divisions such as countries, states and cities. |
