How does wind and water cause erosion?

Answer 1

Water and wind can cause erosion the a variety of ways, but the overall answer is friction. Water can cause erosion by a) liquid water beating a way at the rock and slowly carving into it over a long period of time b) liquid water picking up sediment and depositing it elsewhere c) liquid water seeping into cracks in the rock and later freezing (thus expanding the water) and prying apart the rock or d) frozen water coming down an incline in the form of a glacier, thus cutting into the rock underneath and carrying rock long distances. Wind mainly causes erosion by picking up small grains of sand or sediment and throwing them into solid rock. This constant pummeling essentially sands down the rock and grinds away at, often leaving behind exotic and colorful rock formations.