Mass movement refers to different types of erosion caused by gravity that make mountains smaller over time. The main agents of erosion are gravity, glaciers, water, and wind. Erosion wears away surface materials and transports them elsewhere via processes like deposition, where sediment is dropped when the agent of erosion loses energy. Types of gravity-caused erosion include slumps, ice wedging, rock falls, rock slides, and mudflows, which typically occur quickly after heavy rain or earthquakes and move materials down steep slopes. Methods to help slow mass movement include planting vegetation, installing drainage pipes, and building retaining walls, but mass movement can never be fully stopped.

1. Mass movement Any kind of erosion by gravity Makes mountains smaller

2. Erosion – wears way surface materials and moves them someplace else

3. Agents of erosion Gravity Glaciers Water Wind

4. Deposition Dropping of sediment when agent of erosion loses energy

5. Gravity erosions Water weakens a layer of soil. Or a strong layers lays on top a weaker layer Mass of material slips down a curved surface Fast Slump Weathering that causes it Physical description Speed Name of erosion

6. Slump

10. Ice wedging - Soils very slowly move down hill Slow Creep

13. Ice wedging heavy rain Blocks of rock work loose of slope and come crashing down often in spring Fast Rock fall Sketch Weathering Description Speed Name

18. After heavy rains or earthquake Whole layer of rock slips down hill Fast Rock slide Sketch Weathering Description Speed Name

19. Fan shaped deposit. Removal of grass ( drought or fire) then heavy rain. Thick layer of loose sediment moves downhill Fast Mudflow Reason /weathering Description Speed Name

20. Mass movement All are on steep slope Gravity causes all Often occur after heavy rain ( or earthquake)

21. Building on slopes. Pros? ( good things) Cons? (bad stuff)

22. Ways to slow mass movement Plant veggies (plants- grass trees) will help hold soil in place. Drainage pipes – to remove water Concrete or stone walls – retaining walls You may slow mass movements but you can never STOP it