How do rocks and soil move downslope?
Mass wasting – is movement in which bed rock, rock debris, or soil moves downslope in bulk, or as a mass, because of the pull of gravity. Landslides is a general term for the slow-to-very rapid descent of rock or soil. Flow – The debris is moving downslope as a viscous fluid.
Which factors can lead to a mass movement?
The factors that cause most mass movement events are the undercutting of steep slopes, the removal of vegetation, earthquakes, and heavy prolonged rainfall. Many mass movement disasters are preceded by development, deforestation, and slope steepening, which weakens the slopes.
What refers to the movement of rock down a slope?
Mass movement, also called Mass Wasting, bulk movements of soil and rock debris down slopes in response to the pull of gravity, or the rapid or gradual sinking of the Earth’s ground surface in a predominantly vertical direction. …
What is the difference between mass movement and erosion?
Erosion is the dislodging of sediments that initiates their movement. Particles may then be moved away by sediment transport agents such as wind, water, glaciers, etc. Mass movement refers to earth materials moving downslope under the influence of gravity, as in rockslides, mudflows, slumps, etc.
What is the significance of the angle of repose to mass movement?
What is the significance of the angle of repose to mass movement? If a slope becomes any steeper than the angle of repose, then material will start moving downslope.
What is the mass movement of flow?
Mass movements (also called mass-wasting) is the down-slope movement of Regolith (loose uncemented mixture of soil and rock particles that covers the Earth’s surface) by the force of gravity without the aid of a transporting medium such as water, ice, or wind. Still, as we shall see, water plays a key role.
How many types of mass movements are there?
There are generally three types of creep: Seasonal, where movement is within the depth of soil affected by seasonal changes in soil moisture and soil temperature. Continuous, where shear stress continuously exceeds the strength of the material.
How do you manage mass movement?
Mass movement control must be primarily preventive: e.g., mapping vulnerable zones, drawing up a land use plan, banning building work or any modification of slopes, and protection in the form of coppice forests.
What is fall in mass wasting?
The most common mass-wasting types are falls, rotational and translational slides, flows, and creep. Falls are abrupt rock movements that detach from steep slopes or cliffs. Rocks separate along existing natural breaks such as fractures or bedding planes. Movement occurs as free-falling, bouncing, and rolling.
Which statement best describes slumping a mass wasting process?
Geology100
| Question | Answer |
|---|---|
| Which statement best describes slumping, a mass wasting process? | a block or blocks of unconsolidated regolith slide downhill along a curved slip surface |
| Which mass wasting process has the slowest rate of movement? | creep |
What is the controlling force in mass wasting?
What is the controlling factor of mass wasting? Gravity is the controlling force behind mass movement.
What are three examples of preexisting slip planes for translational slides?
What are three examples of preexisting slip planes for translational slides? Faults, bedding planes, and joints.
What are the four main triggers of rapid mass wasting?
Major Triggers for Mass Wasting: Water, Slopes, Vegetation Removal & Earthquakes.
How would you recognize a debris flow?
To be considered a debris flow, the moving material must be loose and capable of “flow,” and at least 50% of the material must be sand-size particles or larger. Some debris flows are very fast – these are the ones that attract attention.
What is the name for this maximum slope angle that material can sit without falling down?
2. The maximum angle at which loose material can be inclined without sliding down is called the angle of repose. 3. A slope that is steeper than the angle of repose is unstable and will cause material to slide downhill.
What is the typical angle of repose?
The angle of repose can range from 0° to 90°. The morphology of the material affects the angle of repose; smooth, rounded sand grains cannot be piled as steeply as can rough, interlocking sands. The angle of repose can also be affected by additions of solvents.
What is the name for the maximum slope angle?
Maximum skiable slope angle In fact, snow’s “angle of repose,” the greatest tilt at which snow can stick to the slope, is, at most, 75 or so degrees.
How do you make a slope more stable?
This results in a drier soil that is less susceptible to mass wasting. Stability of slopes can also be improved by: Flattening of slopes results in reduction in weight which makes the slope more stable.
What are the others criteria that must be met in order to promote the slope failure?
Common Causes of Slope Failure
- Steepness of the Slope. It goes without saying that the steeper a slope is, the more unstable it will be.
- Water and Drainage. Water is several times heavier than air.
- Soil Composition. The composition of the slope’s soil is a very important consideration when it comes to mitigating slope failure.
- Joints & Fractures.