R horizon

Definition

The R horizon refers to unweathered bedrock that lies beneath all other layers of soil. It consists of solid rock that has not undergone any significant weathering or decomposition.

Related terms

Weathering:

The process by which rocks are broken down into smaller particles by physical, chemical, or biological means.

Erosion:

The movement and transportation of weathered materials (such as rocks, sediments, or soils) by wind, water, ice, or gravity.

Sedimentation:

The deposition or accumulation of eroded materials (such as sand, silt, or clay) in new locations.