Freeze thaw weathering
-freeze thaw weathering is a natural process that occurs when water penetrates a road surface and expands while it is freezing.

Onion Skin Weathering
-onion skin weathering is a phenomenon which occurs in arid or semi arid areas. The drastic changes in daily temperature cause the outer layers of rock to break and peel off resembling the outer layers of an onion.

Biological weathering
-biological weathering is the eating away of rocks by plants and animals. This can be caused by people walking over rocks, burrowing animals or even plants that grow out of cracks in rocks.

Chemical weathering
-chemical weathering is the break down of rocks, soils and minerals through the processes of chemical reactions