1. O Horizon (Organic Layer): This is the top layer, composed of freshly fallen leaves, twigs, and other organic matter. It's rich in nutrients and is typically found in forests.
2. A Horizon (Topsoil): This layer is a mix of minerals and organic matter, formed by the decomposition of the O horizon. It's rich in nutrients and supports plant growth.
3. E Horizon (Eluviated Layer): This layer is found in some soils and is characterized by the leaching of minerals and organic matter. It's often lighter in color than the A horizon.
4. B Horizon (Subsoil): This layer is rich in minerals that have been leached from above. It's often denser and less fertile than the topsoil.
5. C Horizon (Parent Material): This layer is composed of the weathered bedrock from which the soil formed. It's often less developed than the layers above.
6. R Horizon (Bedrock): This is the solid, unweathered rock that lies beneath the soil. It's often not considered part of the soil profile.
It's important to note that:
* Not all soils have all of these layers.
* The thickness of each layer can vary greatly.
* The order of the layers can be different in different soils.
This is a basic overview of soil layers, and there is much more to learn about soil science.
