However, many geographic areas experience creep because of human activity and unfavorable geologic activities. It shows slight deformations in the pavement caused by the creep. This is an exampe of the soil that is very susceptible to creep: with excess of water this soil slowly reduces its volume, causing slope deformations. Skip to main content. Mass Movement: Landslides.
Search for:. Reading: Slumps and Creeps Slump moves materials as a large block along a curved surface. Mass movement control must be primarily preventive: e. A rockslide is the sliding of rock material down a mountain. A debris flow is the movement of a water-laden mass of loose mud, sand, soil, rock and debris down a slope.
A debris flow can dash down the slope, reaching speeds of miles per hour or greater. Engineering solutions include barriers and retaining walls, drainage pipes , terracing the slope to reduce the steepness of the cuts, and immediate revegetation. Rockfalls can be controlled or eliminated by the use of rock bolts, cables, and screens and by cutting back slopes to lesser gradients.
Curves in tree trunks indicate creep because the base of the tree is moving downslope while the top is trying to grow straight up figure 2. Tilted telephone or power company poles are also signs of creep. Figure 2. Trees with curved trunks are often signs that the hillside is slowly creeping downhill. Mass movement is an erosional process that moves rocks and sediments downslope due to the force of gravity.
The material is transported from higher elevations to lower elevations where other transporting agents like streams or glaciers can pick it up and move to even lower elevations. The base of the corrie becomes deeper due to abrasion. As the glacier gets heavier it moves downhill. The glacier moves out of the hollow in a circular motion called rotational slip. Creep refers to a material science concept that describes the likelihood of a material to deform under an applied force of mechanical stress.
Creep may also be known as material creep or cold flow. The Process. One example of soil creep in real life is from the wealthy Caribbean nation of Trinidad and Tabogo. When soil on a hillside or incline freezes, the material expands, and then, when it thaws, is pulled back down, ending up further down the hill than it was before because of the gravitational tug.
Mass movements can sometimes be avoided by employing engineering techniques to make the slope more stable. Among them are: Steep slopes can be covered or sprayed with concrete covered or with a wire mesh to prevent rock falls. The water is increasing pore space which is making the land move that much easier creating a landslide effect.
Figure 3 shows the drastic elevation changes and the effects that slumping is creating. The owner has added rocks to the stream to slow down the speed of the drainage as seen in figure 4. You can only realistically slow down the effect in this situation because the area will still be saturated with rain water and snow melt through the year which will then still cause the slumping to happen.
Our advice to the land owner is to relocate their house before it starts to descend its way down the slope along with the land around it.
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