What’s the Difference Between Weathering and Erosion?

Rocks don’t stay the same forever—they break down, move, and change shape over time! Two important processes that change the land are called weathering and erosion. They sound similar, but they’re not the same.

Let’s dig into the difference!

What is weathering?

Weathering is when rocks break down into smaller pieces, but they don’t move anywhere.

Weathering happens because of things like:

• Rain and ice

• Wind

• Plant roots

• Temperature changes

Example:

If water gets into a crack in a rock and freezes, it can make the crack bigger and break the rock apart. This is called freeze-thaw weathering.

Think of weathering as breaking, not moving.

What is erosion?

Erosion is when rocks and soil get moved from one place to another by:

• Water (rivers, rain)

• Wind

• Ice (like glaciers)

• Gravity

Example:

The Colorado River slowly carved the Grand Canyon by picking up tiny bits of rock and carrying them downstream over millions of years. That’s erosion!

Erosion = movement. It carries things away.

Easy way to remember the difference: weathering vs erosion

Term	What It Does	Moves?	Easy Way to Remember
Weathering	Breaks down rocks	❌ No	“It weathers in place”
Erosion	Moves rocks & soil	✅ Yes	“It erodes and goes!”

Why are weathering and erosion important?

They help shape the land around us! Hills, valleys, cliffs, and beaches are all changed by weathering and erosion over time. These natural forces even help create soil, which we need to grow food.

Where can I weathering or erosion examples in the U.S.?

• Weathering: Tree roots breaking sidewalks or rocks in Appalachian forests.

• Erosion: Wind shaping sand dunes in Arizona or water carving canyons in Utah and Colorado.

• Both: On beaches like Cape Cod or California’s coast, where cliffs slowly break down and wash into the ocean.

Weathering and Erosion Fun Facts!

• The Statue of Liberty turns green because of chemical weathering from rain and air.

• A glacier is slow-moving ice that causes both weathering (it grinds rock) and erosion (it carries rock away).

• Some caves form when rainwater slowly dissolves limestone underground—that’s weathering!