Mass wasting
5 questions tagged Mass wasting — spanning every one of the seven Ws.
What is a debris flow?
A debris flow is a fast-moving mixture of water, soil, rock, and debris that rushes downhill like wet concrete.
How do landslides start on steep slopes?
They begin when gravity overcomes the strength of rock or soil. Triggers can include heavy rain, earthquakes, volcanic activity, or erosion that undercuts the slope.
Why do some landslides happen after heavy rain?
Heavy rain can soak into soil and rock, adding weight and reducing friction on slopes. Once the slope becomes unstable, it can suddenly fail and move downhill.
How do landslides happen after heavy rain or earthquakes?
Slopes fail when gravity overcomes friction, often because water, shaking, or weak rock reduces stability.
How do landslides move so fast down a slope?
Gravity pulls unstable material downhill, and water, shaking, or weak rock can reduce friction. In some cases, landslides accelerate into debris flows or rock avalanches.