Frost Wedging

Frost wedging is a process by which rocks are broken apart due to the repeated freezing and thawing of water within its pores or fractures.

Frost wedging, also called "freeze thaw cycling", is an important way that sediment is physically created from hard rocks, such as igneous or metamorphic rocks exposed in large mountain ranges. As water infiltrates the pores or fractures of a rock during the day, it freezes at night. Freezing water results in a volume increase of 9% versus liquid water. In a confined space, tremendous pressure is exerted on the rock by the ice causing the rock to break open.

Over time this process repeats and breaks rock down into smaller sediments. Chemical dissolution and other forms of weathering assist in creating the final clays, silts and sands we see transported downstream by erosion

This experiment we will demonstrates how freezing water can physically weather solid material by breaking it apart.


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