Soil formation: begins with the weathering (break down) of rock by physical processes (ice, slat crystals, plant roots, unloading) or chemical weathering (chemical reactions with oxygen - ex., rust - , water - forming clays, or acids - dissolving rock).
Soil erosion begins with splash erosion - force on rain drops hitting soil, particularly on bare soil. Creates net downslope movement of particles. Makes the soil surface denser and less permeable, so get more surface runoff
TYPES OF EROSION: a) Splash Erosion: results when water droplets break soil particles apart and carry them a few distance away b) Rill Erosion: a rill is the smallest channel eroded by the flow of water or any liquid. c) Gully Erosion: the last stage of erosion during which running water, wind and glacier create deep valley channels on the surface