What is found in the bottom layer of a soil profile?

The bottom layer of a soil profile is typically composed of unweathered bedrock, which is the solid rock layer beneath the soil. This layer represents the starting point for soil formation, providing the parent material from which soil develops over time through processes like weathering and organic activity.

Unweathered bedrock does not undergo significant alteration or decomposition, retaining its original structure and mineral content. Above this layer, you find various horizons of soil that change in composition, texture, and organic content due to factors like biological activity, weathering, and environmental conditions.

Organic matter and topsoil are found above the bedrock, serving vital roles in supporting plant life by providing nutrients and moisture. Weathered soil is also typically located above the unweathered bedrock, where physical and chemical processes have begun to break down the rock into smaller particles, leading to the formation of soil.