1. Physical Weathering: This involves the breakdown of rocks into smaller pieces without changing their chemical composition. Think of it like breaking a cookie into crumbs.
* Frost Wedging: Water seeps into cracks in rocks, freezes and expands, putting pressure on the rock. This repeated freezing and thawing can cause the rock to break apart.
* Abrasion: Rocks rub against each other, often due to wind, water, or glaciers, causing them to wear down and break into smaller pieces.
2. Chemical Weathering: This involves changes in the chemical makeup of rocks, leading to their breakdown.
* Oxidation: Iron in rocks reacts with oxygen, forming iron oxide (rust). This rust is weaker than the original rock and can cause it to break down.
* Acid Rain: Rainwater, often made acidic by pollutants, reacts with rocks like limestone, dissolving them over time.
3. Biological Weathering: This involves living organisms contributing to rock breakdown.
* Plant Roots: As roots grow, they can wedge into cracks in rocks, eventually breaking them apart.
* Lichens: These organisms produce acids that can break down rock surfaces.
These weathering forces work together, often over very long periods, to transform large rocks into the smaller particles that make up soil.
