The softer parts of the rocks are worn away first. This gives the rocks different shapes. The rocks are slowly worn away. Grains of sand are often swept up into the air, carried far away, and finally settle to the earth in layers. Dust storms are prevalent in the Great Plains of the United States.
Dust is spread much thinner than sand and covers a much larger area.
While dust storms rage, the air is filled with choking dust. After the storm passes, dust is left everywhere. Sometimes a thin layer of dust can be deposited thousands of miles away from the point of origin. Dust storms usually occur in areas where the soil is dry, powdery and bare. As strong winds blow over this bare, loose earth, the finer material is carried away and the coarser material is blown long the ground, scraping loose more dust for the wind to pick up.