Erosion is a geological process in which earthen materials (i.e., soil, rocks, sediments) are worn away and transported over time by natural forces such as water or wind; sometimes this is sped up by poor management or other human impacts on land.
What causes it? (Most) erosion is preformed by liquid water, wind, or ice (usually in the form of a glacier). If the wind is dusty, water or glacial ice is muddy, erosion is taking place.
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