| A | B |
|---|
| bedrock | layer of rock beneath the surface |
| horizon | soil layer |
| humus | part of soil formed by decaying organic matter |
| leaching | process in which water washes minerals from topsoil to subsoil |
| pore space | space between particles of soil |
| residual soil | soil that remains on top of the rock from which is was formed |
| soil profile | a cross section of the soil horizon |
| subsoil | soil in the B horizon, or middle layer of soil |
| topsoil | soil in the A horizon, or uppermost layer of mature soil |
| transported soil | soil that is moved away from its place of origin |
