| A | B |
|---|
| weathering | breaking down of rocks and other materials on the Earth's surface |
| mechanical weathering | weathering that does not make changes in the chemical makeup of rocks |
| root-pry | when rocks are broken apart by the growth of roots |
| abrasion | wearing away of a substance by solid particles carried by wind, water or other forces |
| chemical weathering | weathering that involves changes in the chemical makeup of a rock |
| oxidation | process where oxygen combines chemically with another substance |
| stable rock | rock made of minerals that resist chemical weathering |
| bedrock | layer of rock beneath the soil |
| humus | soil formed by decaying material, making it rich and good for growing (fertile) |
| pore space | space between particles of soil |
| horizon | soil layer |
| soil profile | cross sections of soil horizons |
| topsoil | soil in the "A" horizon |
| leaching | process in which water washes minerals from the topsoil down to the subsoil |
| subsoil | soil in the "B" horizon, or middle layer of the soil |
| topography | shape and steepness of landscape |
| biota | organisms that live in a region |
| decomposition | process in which once living things get converted to organic matter |
| climate | weather patterns over a long period of time |
| parent material | starting material of a soil |
| ice wedging | water in cracked rocks expands breaking the rocks |
