CHEMICAL WEATHERING

TEMPERATURE CHANGES

FREEZE-THAW

WIND, RAIN, WAVES

BIOLOGICAL WEATHERING

When rocks are weathered by chemicals it is called chemical weathering. An example of this is when acid rain reacts with limestone.

As the temperature increases, rocks expand and then contract as the temperature falls. Over time this can cause the rock to crack and small pieces fall away.

Water can get into the cracks of rocks. When the water freezes, it expands, causing the crack to get bigger. As the ice melts, the water goes deeper into the crack and can freeze again, making the crack even bigger.

Wind can blow small particles which wear away the rock. Waves and rain wear the rock down over long periods of time.

Biological weathering is due to animals and plants. Burrowing animals and plant roots can damage and break rocks apart.

Weathering