In a normal soil profile, which layer is the deepest and often referred to as bedrock?

In a normal soil profile, which layer is the deepest and often referred to as bedrock?

• A. Topsoil
• B. Subsoil
• C. Lower subsoil
• D. Sand

Answer: (C)

Soil profiles are arranged in layers called horizons from the surface downward. The uppermost productive layer is topsoil, beneath it is the subsoil, and deeper still you have the lower part of the subsoil. The next layer would be the weathered parent material, and below all of that lies bedrock, the solid rock underneath the soil. Among the given options, the deepest soil-related layer is the lower subsoil, because it is the deepest portion of the subsoil zone just above the weathered material. Bedrock itself sits below all the soil horizons, and sand is a texture, not a horizon. So the deepest layer listed here is the lower subsoil.

Soil profiles are arranged in layers called horizons from the surface downward. The uppermost productive layer is topsoil, beneath it is the subsoil, and deeper still you have the lower part of the subsoil. The next layer would be the weathered parent material, and below all of that lies bedrock, the solid rock underneath the soil.

Among the given options, the deepest soil-related layer is the lower subsoil, because it is the deepest portion of the subsoil zone just above the weathered material. Bedrock itself sits below all the soil horizons, and sand is a texture, not a horizon. So the deepest layer listed here is the lower subsoil.