Earth Science

2. consists of clay and other particles washed down from the A horizon, but little humus.
7. process that breaks down rock and other substances at Earth's surface.
8. loose weathered material on Earth's surface in which plants can grow.
9. grinding away of the rock by rock particles carried by water, ice, ind or gravity.
10. weathering process that breaks down rock through chemical changes.
12. measure of how well the soil supports plant growth.
14. soil that is made up of about equal parts of clay, sand and silt.
15. soild layer of rock beneath the soil.

1. dark-colored substance that forms as plant and animal remains decay.
3. iron combines with oxygen in the presence of water in a process.
4. material is full of tiny connected air spaces that allow water to seep through it.
5. crumbly dark brown soil that is a mixture of humus, clay and other minerals.
6. weathering rock is physically broken into smaller pieces.
11. removal of rock particles by wind, water, ice or gravity
13. wedging process that splits rock when water seeps into cracks, then freezes and expands.