What type of soil is developed directly on the rock beneath it?

Residual soil is formed in place from the weathering of the underlying bedrock, meaning it develops directly on the rock beneath it. This process involves the physical and chemical breakdown of the parent rock material over time, resulting in a soil layer that reflects the mineral composition and characteristics of the underlying rock.

As weathering occurs, minerals are released and organic matter may accumulate, but the key aspect is that residual soil originates from the rock without any significant movement or transportation of material from another location. This distinguishes it from transported soil, which is formed from materials that have been moved from their original location through processes such as wind or water, often leading to a varied composition compared to the rock beneath.

Recognizing the placement and formation dynamics of residual soil is crucial for understanding soil behavior in engineering, environmental impact assessments, and land use planning.