While soil development is influenced by deeper layers, the initial process of soil formation starts with the weathering of bedrock and other materials at the surface.

Here's a breakdown:

* Parent Material: The bedrock or sediments that form the foundation for soil development. Weathering processes like frost wedging, chemical reactions, and biological activity break down this parent material.

* Weathering: This is the initial step in soil formation. It's the process by which rocks, minerals, and other materials are broken down into smaller particles.

* Organic Matter: As plants and animals die and decompose, they add organic matter to the surface layers, enriching the soil and contributing to its development.

Therefore, while soil development continues in depth over time, the initial stage of soil formation begins at the Earth's surface.