| A | B |
|---|
| weathering | The processes that break apart and change the chemical makeup of rocks |
| plates | Huge movable blocks of the earth's crust that slowly move over the mantle |
| physical change | The change in size or shape of something |
| chemical change | Any change that affects the chemical makeup of something |
| frost action | The weathering of rock by repeated freezing and melting of water |
| acid rain | A mixture of acid and rain water |
| oxidation | A chemical reaction that takes place when oxygen combines with other substances |
| soil | The loose material on the earth's surface in which plants can grow |
| topsoil | The upper layer of soil |
| humus | The decayed remains of plant and animal matter in soil |
| subsoil | The soil just below the topsoil |
| erosion | The picking up and moving away of weathered rock and soil |
| deposition | The dropping of sediment by agents of erosion |
| glacier | A large body of moving ice |
| sediment | Rock and soil being carried away |
| windbreaks | A fence or row of trees that provides protection from the wind |
| delta | A triangular or fan-shaped piece of land made by deposits of sediment at the mouth of a river |
