mass wasting, or mass movements: movement of geological meterials downward, from one place to another.

Landslide: is a general term for the results of rapid mass movements

shearing stress: the down slope pull tending to cause mass movements. shearing stress is related to the mass of the material and the slope of the angle. friction counter acts the shearing force. shear strength is the maximum resistance

angle of repose: is the maximum slope angle at which material is stable

frost heaving: the expansion of wet soil as it freezes and the ice expands, loosens and displaces the soil.

plant roots can provide support for loose material.

when down slope movement is quite slow, the motion is called creep. it is the most common type of mass movement and a sign of it can be the bending of trees upward on a slope.

landslide: is a nonspecific term for rapid mass movements in rock or soil. the rate of motion is usually increased by the content of moisture.

fall: is a free falling action in ewhich the moving material is not always in contace with the ground below it. falls are most often rock falls. usually on very steep slopes.

the coarse rubble that accumilates at the foot of a slope prone to rock falls is called talus.

a slide is a fairly cohesive unit of rock that slides down hill as a unit. usually involves a large portion of a hillside etc...

slumps: can occur in rock or in soil.

a scarp may be formed at the top of a slide, it is a relatively undisturbed portioin at the top of a slide

a rock slide that does not move very far may also be a slump

in a flow the material moved is not coherent, but moves in a chaotic, disorganized fashion. these are extremely common. avalanches are one type of flow. as are nuees ardentes and pyroclastic flows

where soil is the flowing material it may be called an earth flow or mud flow (if saturated with water) a flow involving a large variety may be called a debris avalanche

land slides into a stream can dam it and creat a natural lake that will often be very unstable

steps to reduce slide potential:

1 reduce the slope angle

2 place material at the foot to help support

3 reduce the laod weighton the slope on the higher levels

since water is such a factor, another startegy is reduce the water content of the soil.

Causes of Mass Wasting:

1. slope

2. climate

3. water

4. vegetation

5 overloading

6. geology