Erosion or Weathering? What is the Difference?

erosion or weatheringHave you ever heard of or do you know about erosion or weathering?  Maybe you do, but did you know most people incorrectly use the term erosion?

Rocks change from one of the three main kinds of rock to another through the rock cycle.  The rock cycle includes many different steps, such as melting rock into magma.  But, the actual processes that change a large rock into smaller pieces and move those pieces elsewhere is called either erosion or weathering.  Here is a short explanation of the difference between weathering and erosion.

erosion or weathering

Goblin Valley State Park in southern Utah.


Weathering is the first step of the two step process that breaks down rocks and moves them elsewhere.  Weathering is the process of breaking down rocks into smaller pieces.

Weathering of rocks can take place both by physical means and chemical ones. Physical changes break down large rocks into smaller ones but the rocks are made of the same stuff. Chemical weathering actually changes the make-up of the rock itself.


Erosion is the process by which these smaller pieces or fragments of rocks are picked up and moved somewhere else.  Erosion or the movement of small rock fragments can be done by blowing wind, running water, or moving ice.

erosion or weathering

Amazing sandstone slot canyon in southern Utah.  These amazing features are caused by a combination of weathering and erosion working together.  Most people say the rock was eroded away when in fact the rock was broken down by weathering and then the small pieces were moved by erosion.

Weathering And Erosion Work Together

Weathering and erosion act together to shape the landscape.  The rocks all over the landscape are slowly broken down by weathering.  Then those small pieces of rock, sediment, are moved by erosional processes, such as rain or wind, and moved somewhere else.

They have worked together over time to shape the Rocky Mountains.  In the past the Rocky Mountains were 20,000 feet high and weathering and erosion have lowered them by 5,000 feet into the peaks, valleys, and plains we see today.