| A | B |
|---|
| abrasion | The grinding away of rock by other rock particles carried in water, ice, or wind. |
| batholith | A mass of rock formed when a large body of magma cooled inside of crust. |
| bedrock | The solid layer of rock beneath the soil. |
| chemical weathering | The process that breaks down rock through chemical changes. |
| dike | A slab of volcanic rock formed when magma forces itself across rock layers. |
| erosion | The process by which water, ice, wind, or gravity moves fragments of rock and soil. |
| humus | Dark-colored organic material in soil. |
| ice wedging | Process that spilts rock when water seeps into cracks, then freezes and expands. |
| loam | Rich, fertile soil that is made up of about equal parts of clay, sand, and silt. |
| mechanical weathering | The type of weathering in which rock is physically broken into smaller pieces. |
| permeable | Characteristic of materials such as sand and gravel that allow water to pass easily through them. |
| sill | A slab of volcanic rock formed when magma squeezes between layers of rock. |
| soil | The loose, weathered material on Earth's surface in which plants can grow. |
| volcanic neck | A deposit of hardened magma in a volcano's pipe. |
| weathering | The chemical and physical processes that break down rock at Earth's surface. |
