Vocabulary #15 (Building up and breaking down)

Definitions:

1. fold mountain: a mountain made mostly of rock layers folded by being squeezed together
2. fault-block mountain: a mountain made by huge tilted blocks of rock separated from surroundings by faults
3. weathering: the breaking down of rocks into smaller pieces by natural processes
4. erosion: the picking up and removal of rock particles
5. soil: a mixture of weathered rock, decayed plant and animal matter, living things, air, and water
6. soil horizon: any of the layers of surface to the bedrock below
7. groundwater: water that soaks into soil and rock by collecting in spaces between rock particles
8. humus: material in soil formed by the break down of plant and animal material.

Sentences and illustrations:

1. The most common type of mountain is a fold mountain.

2. A fault-block mountain is made by huge tilted blocks of rocks separated from surrounding rock by faults.

3. Weathering is one of the main forces that are breaking down Earth's surface.

4. Erosion is the picking up and removal of rock fragments and other particles.

5. The end result of weathering is soil.

6. Slowly the soil develops distinct layers, called soil horizons.

7. A groundwater system is something like a river system.

8. Soil can be improved by adding humus.