1. LANDSLIDES

2. Thorp Landslide 1970

3. What Causes Landslides?  Weak substrate  Weathering of material  Jointed and/or sheared substrates  Discontinuity in the outcrop  Contrast between the stability and permeability of layers of material  Tectonics  Volcanism  Glacial rebound  Water/glacial erosion at the toe or lateral margins  Deep or underlying erosion of materials  Depositional loading of the slope  Removal of vegetation  Freeze-thaw processes  Shrink-swell processes Geological CausesMorphological Causes

4. Human Causes  Slope excavation  Slope loading  Deforestation  Irrigation  Mining  Artificial vibrations  Water leakage from pipes (utilities)

5. Parts of a Landslide

6. Types of Landslides

9.  What variables trigger landslides?  What variables can we control/test?

10. Design Your Experiment  What is your question?  Do background research  Construct a hypothesis  Test your hypothesis by doing an experiment  Record and analyze your data and draw a conclusion/summarize  Communicate your results

11. Landslide Lab Materials 1 clear container Earth materials: Sand Soil Gravel Snow (optional) Twigs, grass, etc. for vegetation cover 1 Graduated cylinder 1 Watering can or spray bottle 1 Protractor (to measure slope angle) 1 Scale 1 Stopwatch