Mass wasting is the movement of soil and rock down a slope due to gravity. It can be caused by a variety of factors, including water, ice, wind, and earthquakes. Water is the most common cause of mass wasting, and it can occur in a variety of forms, including rain, snowmelt, and runoff. When water accumulates on a slope, it can create a saturated zone where the soil and rock are weakened. This can lead to landslides, debris flows, and other types of mass wasting.