1. Mass Movements
SWBAT identify factors that affect mass movements; relate how mass movements affect people; analyze the relationship between gravity and mass movements

2. Mass Movements Why do you think these trees are tilted?
What might happen if a house was built on this hillside?

3. Mass Movements Mass movement Variables that influence mass movement:
The downslope movement of loose sediments and weathered rock resulting from gravity.
Variables that influence mass movement:
Gravity
Pulls materials downslope
Materials resistance to sliding or flowing
Trigger
Earthquake
Erosion and undermining at bottom of slopes
Water

4. Types of Mass Movement Creep
Slow steady downhill flow of loose weathered earth, especially soil
Takes a long period to see the results

5. Types of Mass Movement Flow
Earth materials move as if they were a thick liquid.
Earth flows are moderately slow moving where mudflows are fast and usually triggered by something.

6. Types of Mass Movement Slide
A rapid downslope movement of earth materials that occurs when a thin black of loose soil, rock, or debris separates from the underlying bedrock.
Landslide can reach speeds of 200km/h

7. Types of Mass Movement Slump
When a mass of material in a landslide rotates and slides along a curved surface.

8. Types of Mass Movement Avalanche
Landslides in mountainous areas with thick accumulations of snow
Usually occur on a slope of 35° or more
Melting and refreezing causes the top to become heavy and fall or slip down the slope

9. Types of Mass Movement Rock fall
Occur at high elevation in steep road cuts and on rocky shorelines
Weathered rocks fall downward where they bounce and roll producing come shaped piles of coarse debris

10. Mass Movements Affect People
What are some preventative actions we can take to help avoid mass movements?
Don’t build on steep slopes
Create channels to divert water
Cover steep slopes with metal nets or protective fences.