Soil Layers Learning SimulationInteractive Educational Soil Layer Formation Simulator. |
Begin the simulation by selecting Cold or Warm from the Set Temperature box. Learn more about the factors contributing to soil formation by rolling over the items in the Factors in Soil Formation box.
Soil forms as rock is broken down by weathering and mixes with other material on the surface. Soil is constantly being formed wherever bedrock is exposed. Over time, soil develops layers called horizons. A soil horizon is a layer of soil that differs in color and texture from the layers above or below it. Water, plant growth, rock type, and temperature are all factors that affect soil formation.
The A horizon is made up of topsoil, a crumbly, dark brown soil that is a mixture of humus, clay, and other minerals. The B horizon, often called subsoil, usually cosists of clay and other particles. The first soil to form from the weathering of bedrock is the C horizon. It contains only partly weathered rock.