Transport of clastics (weathering is precondition)
-modified particle size and shape
-sorts clastics

Erosion = Weathering + transport

Grain size and sorting

Variables
Velocity and viscosity of transport medium.

Landslides: one of the most costly of natural hazards

subaerial
subaqueous

Mass Movement
-cause: oversteepening of slopes
-forces: gravity, friction & shearing stress
-nature of movement:
*creep solifluction
*flow: mudflow and earth flow debris avalanche slump
*slide: rockslide
*fall: rockfall

1. Identify and briefly describe the two principle effects that sediment transport has on the particles transported.
2. Describe the process of solifluction. Your answer should include but not be limited to the role of climate, moisture content of the regolith, as well as rate of movement.
3. Draw a labeled cross-section through a hillside which has been affected by slump. What conditions predispose an area to slumping? What steps can be taken to minimize slumping?
4. Identify two geologic conditions which should be evaluated before building a house at the base of a steep, soil-covered hill.
5. Use a labeled diagram to help you explain how creep operates on a soil covered hillside. Since creep is an imperceptible slow process, what evidence would you look for to determine whether or not creep is affecting a particular slope.
6. What type of deposit is generally found at the base of a cliff subject to frequent rock falls? Why does the surface of this deposit stand at a characteristic slope angle?
7. What is the distinction between a fall, a slide and a flow? Briefly describe the role of H₂0 in these different types of mass movement.
8. Identify and briefly describe one natural event and one human activity which can destabilize a slope and trigger a sudden slope failure.
9. Would prolonged drought have any effect on the frequency of landslides? Why?

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